PDLC display panel

Abstract

An electrically driven multi-region PDLC panel and associated methods and systems for selective transparency. A PDLC region has input and ground conductive coatings; an input gate charges the input coating and a draining gate actively discharges it, forming a half-bridge that provides zero-mean AC drive. Adjacent regions may be driven with phase-shifted AC at a shared frequency using ±DC rails in a SELV-like envelope; effective voltage may be modulated by PWM with optional low-pass filtering in accordance with an opacity response curve. Regions are isolated in a transparent conductor; perimeter routing and flexible interconnects are disclosed. A retrofit overlay employs an interconnect bus and an edge control module that receives AC power and a data signal from an external control module, with daisy-chain capability. A system maps transparency-map data to panel regions; a controller drives the PDLC to render images, views, and obstructions.

Description

PDLC DISPLAY PANELPRIORITY STATEMENT

[0001] This non-provisional patent application claims priority based upon the prior U.S. provisional patent application entitled "PDLC DISPLAY PANEL”, application number 63 / 691 ,699, filed on September 6, 2024, in the name of ANTIMODULAR RESEARCH INC., incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] The present invention relates to a display, and, more particularly, to the configuration of multiregion Polymer-Dispersed Liquid Crystal (PDLC) panels.BACKGROUND

[0003] Polymer-Dispersed Liquid Crystal (PDLC) panels use materials that integrate liquid crystal droplets dispersed within a polymer matrix. These panels exhibit optical properties that can be dynamically controlled by applying an external electric field. When no electric field is applied, the liquid crystals are randomly oriented, causing the panel to scatter light and appear opaque or translucent. Upon application of an electric field, the liquid crystals align in a uniform direction, allowing light to pass through and rendering the panel transparent. This switchable nature of PDLC panels allows for versatile applications, making them suitable for a wide range of uses.

[0004] Typically, PDLC panels are employed in architectural and interior design for privacy glazing, where they can transition from transmissive (transparent) to scattering (opaque) to provide privacy on demand. They are also used in smart windows and skylights to control the amount of natural light entering a space, thereby enhancing energy efficiency and occupant comfort. Additionally, PDLC technology finds applications in automotive and aerospace industries for adjustable transparency in sunroofs and windows, as well as in consumer electronics for display screens and augmented reality devices.

[0005] Despite their versatile applications, Polymer-Dispersed Liquid Crystal (PDLC) panels have several limitations that, in many implementations, limit their performance and usability. Driving PDLC panels often requires an alternating current (AC) signal with a relatively high voltage, typically in the range of 50-110 volts, to effectively switch the liquid crystals between their scattering and transmissive states.

[0006] Moreover, PDLC panels may not be well-suited for applications that require fast refresh rates. While they can quickly transition from a scattering to a transmissive state, the reverse transition— from transmissive to scattering— is generally slower. This latency is due to the nature of the liquid crystals,which may need more time to reorient randomly once the electric field is being removed. This delay limits their use in dynamic applications where rapid switching is essential.

[0007] PDLC panels are typically used in binary on / off situations, where the panel is either fully transparent or fully opaque. This restricted use case is largely due to the challenges in achieving and controlling intermediate states of transparency. Additionally, PDLC panels are generally controlled as a single unit, meaning that the entire panel switches states uniformly. This lack of granular control limits the potential for more sophisticated applications. There is a need for a versatile multi-region PDLC panels. The present disclosure may address at least some of these issues.SUMMARY

[0008] This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0009] In a first aspect, the technique described herein relates to a method for driving a Polymer- Dispersed Liquid Crystal (PDLC) panel. At a PDLC region of the PDLC panel, a back side of the PDLC region may be grounded to a ground connection. A voltage may be applied to a front side of the PDLC region via a first gate, causing the PDLC region to accumulate a charge and transition into a first transparency state. The charge may be drained from the front side of the PDLC region via a second gate subsequent to interrupting the voltage via the first gate, causing the PDLC region to transition into a second transparency state. One of the first transparency state and the second transparency state may be an at least partially transmissive state and the other may be an at least partially scattering state.

[0010] Optionally, the PDLC region may transition into the second transparency state within 50 ms after closing the second gate.

[0011] In embodiments, the first gate and the second gate may form a half-bridge between a supply rail and the ground connection, the half-bridge having a switching node electrically coupled to the front side of the PDLC region.

[0012] In embodiments, the voltage applied to the front side may include an alternating current (AC) signal.

[0013] In embodiments, the PDLC panel may be a multi-region PDLC panel. The back side of each of two or more adjacent PDLC regions may be grounded to the ground connection. Two or more phase- shifted alternating current (AC) signals may be generated with a common frequency. The two or more phase-shifted AC signals may be respectively distributed to respective front sides of the two or moreadjacent PDLC regions of the multi-region PDLC panel. Optionally, the common frequency may be between 60 Hz and 120 Hz.

[0014] In embodiments, the two or more phase-shifted AC signals may be uniformly phase-spaced from one another.

[0015] In embodiments, generating the two or more phase-shifted AC signals may include alternating between a positive Direct Current (DC) supply and a negative DC supply to balance a load of the two or more phase-shifted AC signals across the positive DC supply and the negative DC supply.

[0016] In embodiments, the positive DC supply may be less than 57 volts and the negative DC supply may be greater than -57 volts.

[0017] In embodiments, an opacity response curve of the PDLC region may be obtained. An alternating current (AC) signal may be provided to a front side of the PDLC region. The AC signal may be modulated according to the opacity response curve.

[0018] In embodiments, the AC signal may be interrupted according to a Pulse-Width Modulation (PWM) signal to generating a PWM-modulated AC signal.

[0019] In embodiments, the PWM-modulated AC signal may be filtered with a low-pass filter.

[0020] In embodiments, the PDLC panel may be a multi-region PDLC panel. A region identifier to a region of the multi-region PDLC panel may be assigned. A configuration stream may be received, with the region identifier and a region configuration. An alternating current (AC) signal may be modulated according to the region configuration via a region controller configured to drive the region corresponding to the region identifier. Optionally, the configuration stream may be a Digital Multiplex (DMX) data stream.

[0021] In embodiments, prior to driving the PDLC panel, a plurality of PDLC regions may be isolated within a transparent conductive coating of the PDLC panel. At least one PDLC region of the plurality of PDLC regions may be connected to a region controller configured to drive the at least one PDLC region.

[0022] In embodiments, a substrate carrying a transparent conductive coating may be provided. The transparent conductive coating may be patterned to form isolation channels in the transparent conductive coating. Optionally, the transparent conductive coating may be ablated using a laser prior to lamination to a PDLC layer.

[0023] In embodiments, the patterned substrate may be laminated to a PDLC layer, thereby defining the plurality of PDLC regions.

[0024] In embodiments, the transparent conductive coating may include indium tin oxide (ITO) deposited on a polymeric substrate.

[0025] In embodiments, the isolation channels may have a width less than 100 m and the IT 0 sheet resistance is between 10 Q / sq and 200 Q / sq.

[0026] In embodiments, prior to driving the PDLC panel, a second substrate carrying a transparent conductive coating may be provided. The transparent conductive coating of the second substrate may be patterned to form conductive traces routed from a perimeter of the PDLC panel toward interior locations. The second substrate and a PDLC layer may be laminated with a dielectric interlayer therebetween. Conductive interconnects may be formed between the conductive traces and input conductive coatings of selected PDLC regions.

[0027] In embodiments, the PDLC region may be connected using a flexible Printed Circuit Board (PCB). Optionally, the flexible PCB and the region controller may be embedded within a perimeter frame of the PDLC panel. Optionally, the flexible PCB may be bonded to contact pads using an anisotropic conductive film (ACF).

[0028] In a second aspect, the technique described herein relates to a method for retrofitting a glazing with a multi-region Polymer-Dispersed Liquid Crystal (PDLC) panel overlay. A PDLC panel overlay may be attached to an exposed surface of the glazing, the PDLC panel overlay comprising a plurality of PDLC regions, an interconnect bus along at least one edge of the PDLC panel overlay, and electrical coupling between the interconnect bus and an input conductive coating of the plurality of PDLC regions.

[0029] In embodiments, the interconnect bus may be connected to an edge control module. Alternating current (AC) power and a data signal may be supplied to the edge control module from an external control module. The data signal may be adjusted to drive the plurality of PDLC regions via the edge control module.

[0030] In embodiments, attaching the PDLC panel overlay may include applying an optically clear adhesive and / or installing a secondary frame retained within a window reveal of the glazing.

[0031] In embodiments, the edge control module may be mounted within a perimeter frame of the glazing.

[0032] In embodiments, the PDLC panel overlay may be a first PDLC panel overlay and the edge control module may be a first edge control module. The first edge control module may be connected to a second edge control module. The second edge control module may be configured to drive a second PDLC panel overlay. The data signal may be adjusted to drive the second PDLC panel overlay via the first edge control module and the second edge control module.

[0033] In embodiments, the plurality of PDLC regions may be driven according to the method of the first aspect.

[0034] In a third aspect, the technique described herein relates to a method for displaying a transparency map using a multi-region selective-opacity panel. A transparency map region of a transparency map may be mapped to at least one panel region from a plurality of panel regions of the multi-region selective-opacity panel, and a transparency of the at least one panel region may be configured in accordance with a transparency value of the transparency map region.

[0035] In embodiments, the transparency map may be an image, and the transparency value may be derived from at least one of a transparency channel, an opacity channel, a luminance channel, and / or a grayscale channel of the image.

[0036] In embodiments, the plurality of panel regions may be configured as a regular grid, the image may be a raster image, the image region may be a pixel of the raster image, and mapping the image region may include mapping the pixel to the regular grid.

[0037] In embodiments, the image may be processed to obtain one or more intensity channels and a transparency channel. The transparency of the at least one panel region may be configured in accordance with the transparency channel. Light may be projected onto the multi-region selective-opacity panel in accordance with the one or more intensity channels.

[0038] In embodiments, the one or more intensity channels may include a color channel, a luminance channel, and / or a chrominance channel.

[0039] In embodiments, the image may be a frame from a video stream and the configuring of the transparency may be repeated for successive frames thereof. Optionally, a frame rate of the video stream may be at least 20 frames per second.

[0040] In embodiments, a position of interest may be obtained relative to the multi-region selective-opacity panel. A view pattern may be rendered in the transparency map located relative to the position of interest, the view pattern defining a view region having transparency values greater than those of surrounding regions. Configuring the transparency of at least one panel region corresponding to the view pattern may create a view across the multi-region selective-opacity panel. Optionally, the transparency map may be updated when the position of interest moves. Optionally, the view pattern may have a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person-shaped pattern.

[0041] In embodiments, the position of interest may include a distance relative to the multi-region selective-opacity panel. Configuring may include adjusting at least one panel region of the multi-region selective-opacity panel from an at least partially scattering configuration to an at least partially transmissive configuration when the distance of the position of interest is within a distance threshold. Optionally, a size of the view region may be a monotonically decreasing function of the distance of the position of interest.Optionally, transparency values within the view region may be a monotonically decreasing function of the distance of the position of interest.

[0042] In embodiments, the position of interest may further include an elevation and the view pattern may be located relative to the elevation.

[0043] In embodiments, the position of interest may be a position of an observer and the view may allow the observer to see through the multi-region selective-opacity panel.

[0044] In embodiments, a sight direction of the observer may be obtained and the view pattern may be located relative to an intersection of the sight direction with the multi-region selective-opacity panel.

[0045] In embodiments, the position of interest may be a position of a light source and the view may allow the light source to illuminate through the multi-region selective-opacity panel.

[0046] In embodiments, the position of interest may be a first position of interest located on a first side of the multi-region selective-opacity panel and a second position of interest may be obtained on a second side of the multi-region selective-opacity panel. A line of sight from the first position of interest to the second position of interest may be computed, the line of sight comprising an intersection at the multi-region selective-opacity panel. The view pattern may be located relative to the intersection of the line of sight at the multi-region selective-opacity panel.

[0047] In embodiments, the view may be updated when the second position of interest moves.

[0048] In embodiments, the first position of interest may include a first distance relative to the multi-region selective-opacity panel and the second position of interest may include a second distance relative to the multi-region selective-opacity panel. Configuring may include adjusting at least one panel region of the multi-region selective-opacity panel from an at least partially scattering configuration to an at least partially transmissive configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold.

[0049] In embodiments, the position of interest may be a light source located on a first side of the multi-region selective-opacity panel, and the view region may be configured to allow light from the light source to pass through the panel and project an image onto a surface located on a second side of the panel.

[0050] In embodiments, the multi-region selective-opacity panel may be a first multi-region selective-opacity panel and a first view may be configured thereon. A second view may be configured by adjusting a second transparency of at least one region of a second multi-region selective-opacity panel, allowing an at least partial visibility from the position of interest across the first multi-region selective-opacity panel and the second multi-region selective-opacity panel.

[0051] In embodiments, the position of interest may be a first position of interest and a second position of interest may be obtained on an opposite side of the second multi-region selective-opacity panel. A line of sight from the first position of interest towards the second position of interest may be computed, the line of sight comprising a first intersection at the first multi-region selective-opacity panel and a second intersection at the second multi-region selective-opacity panel. A first view region may be located relative to the first intersection and a second view region may be located relative to the second intersection, allowing at least partial visibility between the first position of interest and the second position of interest across the first view region and the second view region.

[0052] In embodiments, the first position of interest may be an observer and the second position of interest may be an observee, and the at least partial visibility across the first view region and the second view region may allow the observer to see the observee.

[0053] In embodiments, a position of interest may be obtained relative to the multi-region selective-opacity panel. An obstruction pattern may be rendered in the transparency map located relative to the position of interest, the obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions. Configuring the transparency of at least one panel region corresponding to the obstruction pattern may create an obstruction across the multi-region selective-opacity panel. Optionally, the obstruction pattern may be updated when the position of interest moves.

[0054] In embodiments, the obstruction pattern may have a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person-shaped pattern.

[0055] In embodiments, the position of interest may include a distance relative to the multi-region selective-opacity panel. Configuring may include adjusting at least one panel region of the multi-region selective-opacity panel from an at least partially transmissive configuration to an at least partially scattering configuration when the distance of the position of interest is within a distance threshold. Optionally, a size of the obstruction region may be a monotonically decreasing function of the distance of the position of interest. Optionally, an opacity within the obstruction region may be a monotonically decreasing function of the distance of the position of interest.

[0056] In embodiments, the position of interest may further include an elevation and the obstruction pattern may be located relative to the elevation.

[0057] In embodiments, the position of interest may be a position of an observer and the obstruction may prevent the observer from seeing, at least partially, through the multi-region selective-opacity panel.

[0058] In embodiments, a sight direction of the observer may be obtained and the obstruction pattern may be located relative to an intersection of the sight direction with the multi-region selective-opacity panel.

[0059] In embodiments, the position of interest may be a position of a light source and the obstruction may prevent the light source from illuminating, at least partially, through the multi-region selective-opacity panel.

[0060] In embodiments, the position of interest may be a first position of interest located on a first side of the multi-region selective-opacity panel and a second position of interest may be obtained on a second side of the multi-region selective-opacity panel. A line of sight from the first position of interest to the second position of interest may be computed, the line of sight comprising an intersection at the multi-region selective-opacity panel. The obstruction pattern may be located relative to the intersection of the line of sight at the multi-region selective-opacity panel. Optionally, the obstruction pattern may be updated when the second position of interest moves.

[0061] In embodiments, the first position of interest may include a first distance relative to the multi-region selective-opacity panel and the second position of interest may include a second distance relative to the multi-region selective-opacity panel. Configuring may include adjusting at least one panel region of the multi-region selective-opacity panel from an at least partially transmissive configuration to an at least partially scattering configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold.

[0062] In embodiments, the position of interest may be a light source located on a first side of the multi-region selective-opacity panel, and the obstruction region may be used to project a shadow onto a surface located on a second side of the multi-region selective-opacity panel.

[0063] In embodiments, the multi-region selective-opacity panel may be a first multi-region selective-opacity panel, and a first obstruction may be configured thereon. A second obstruction pattern may be rendered by adjusting a transparency of at least one region of a second multi-region selective-opacity panel, thereby preventing a complete visibility from the position of interest across the first multi-region selective-opacity panel and the second multi-region selective-opacity panel.

[0064] In embodiments, the position of interest may be a first position of interest and a second position of interest may be obtained on an opposite side of the second multi-region selective-opacity panel. A line of sight from the first position of interest towards the second position of interest may be computed, the line of sight comprising a first intersection at the first multi-region selective-opacity panel and a second intersection at the second multi-region selective-opacity panel. A first obstruction region may be located relative to the first intersection and a second obstruction region may be located relative to the second intersection, thereby preventing a complete visibility between the first position of interest and the second position of interest across the first obstruction region and the second obstruction region.

[0065] In embodiments, the first position of interest may be an observer and the second position of interest may be an observee, and preventing complete visibility across the first obstruction region and the second obstruction region may prevent the observer from seeing the observee.

[0066] In embodiments, the multi-region selective-opacity panel may include a Polymer-Dispersed Liquid Crystal (PDLC) panel driven according to the method of the first aspect.

[0067] In a fourth aspect, the technique described herein relates to a Polymer-Dispersed Liquid Crystal (PDLC) system. The PDLC system may include a power source, a ground connection and a PDLC panel. The PDLC panel may include one or more PDLC regions, each PDLC region with a front side covered with an input conductive coating, a back side covered with a ground conductive coating, an input gate to selectively connect the input conductive coating to the power source, and a draining gate configured to selectively connect the input conductive coating to the ground connection. With the input gate closed and the draining gate open, the input conductive coating may be charged, causing the PDLC region to transition into a first transparency state. With the input gate open and the draining gate closed, charge may be drained from the input conductive coating, causing the PDLC region to transition into a second transparency state. One of the first transparency state and the second transparency state may be an at least partially transmissive state and the other may be an at least partially scattering state. Optionally, the PDLC region may transition into the second transparency state within 50 ms after the draining gate is closed. Optionally, the input gate and the draining gate may form a half-bridge between a supply rail of the power source and the ground connection, a switching node of the half-bridge being electrically coupled to the input conductive coating.

[0068] In embodiments, the input conductive coating may be driven by an alternating current (AC) signal.

[0069] In embodiments, the PDLC system may further include a controller. Two or more phase- shifted alternating current (AC) signals, having a common frequency, may be generated. The two or more phase-shifted AC signals may be distributed to respective front sides of at least two adjacent PDLC regions of the PDLC panel. Optionally, the common frequency may be between 60 Hz and 120 Hz.

[0070] In embodiments, the two or more phase-shifted AC signals may be uniformly phase-spaced from one another.

[0071] In embodiments, the power source may include a positive Direct Current (DC) supply and a negative DC supply. The controller may be configured to generate the two or more phase-shifted AC signals by alternating between the positive DC supply and the negative DC supply, to balance a load of the two or more phase-shifted AC signals across the positive DC supply and the negative DC supply.

[0072] In embodiments, the positive DC supply may be below 57 volts and the negative DC supply may be greater than -57 volts.

[0073] In embodiments, the PDLC system may further include a voltage modulator electrically connectable between the controller and the input conductive coating of at least one PDLC region. The voltage modulator may modulate an effective voltage of an AC drive signal delivered to the input conductive coating in accordance with an opacity response curve of the at least one PDLC region. The controller may provide AC drive signals.

[0074] Optionally, the voltage modulator may include a Pulse-Width Modulation (PWM) module to apply PWM gating to the AC drive signal to generate a PWM-modulated AC drive signal. Optionally, the voltage modulator may further include a low-pass filter configured to filter the PWM-modulated AC drive signal.

[0075] In embodiments, the controller may provide AC drive signals. The PDLC panel may include a plurality of PDLC regions. The PDLC system may include a communication module and a plurality of region controllers, each being electrically connected to at least one PDLC region and being addressable by a region identifier. Each region controller may modulate an AC drive signal according to a region configuration to drive the PDLC region corresponding to the region identifier. The communication module may receive a configuration stream comprising the region identifier and the region configuration, and may transmit the region configuration to at least one region controller corresponding to the region identifier. Optionally, the configuration stream may be a Digital Multiplex (DMX) data stream.

[0076] In embodiments, the PDLC regions may be electrically isolated from one another within a transparent conductive coating of the PDLC panel. Optionally, the transparent conductive coating may be patterned to form isolation channels in the transparent conductive coating. Optionally, the transparent conductive coating may be laser-ablated to form the isolation channels. Optionally, the transparent conductive coating may be disposed on a substrate that is laminated to a PDLC layer.

[0077] In embodiments, the transparent conductive coating may include indium tin oxide (ITO) deposited on a polymeric substrate. Optionally, the isolation channels may have a width less than 100 pm and the ITO may have a sheet resistance between 10 Q / sq and 200 Q / sq.

[0078] In embodiments, the PDLC panel may include a first transparent conductive layer patterned to define a plurality of PDLC regions and at least one additional transparent conductive layer patterned to form conductive traces routed from a panel perimeter to interior PDLC regions. The additional transparent conductive layer may be electrically coupled to the PDLC regions via electrically conductive interconnects at registered contact points. Optionally, the at least one additional transparent conductive layer may be provided on a second substrate laminated to a PDLC layer with a dielectric interlayer therebetween.

[0079] In embodiments, the PDLC system may further include a flexible printed circuit board (PCB) electrically connected to the transparent conductive coating. The flexible PCB may connect a power source to respective input conductive coatings of the PDLC regions and may connect a ground connection to respective ground conductive coatings.

[0080] In embodiments, the PDLC system may further include a frame and a plurality of region controllers. The flexible PCB and the plurality of region controllers may be embedded within the frame.

[0081] In embodiments, the flexible PCB may be bonded to contact pads using an anisotropic conductive film (ACF).

[0082] In a fifth aspect, the technique described herein relates to a Polymer-Dispersed Liquid Crystal (PDLC) retrofit system. The PDLC retrofit system may include a PDLC panel overlay, a plurality of PDLC regions, an interconnect bus along at least one edge of the PDLC panel overlay, electrical coupling between the interconnect bus and respective input conductive coatings of the plurality of PDLC regions, an edge control module, and an external control module. The PDLC panel overlay may be attachable to an exposed surface of a glazing. The edge control module may be connectable to the interconnect bus. The external control module may supply alternating current (AC) power and a data signal to the edge control module. The edge control module may drive the plurality of PDLC regions via the interconnect bus in accordance with the data signal.

[0083] In embodiments, the PDLC retrofit system may further include an optically clear adhesive and / or a secondary frame retained within a window reveal of the glazing. The PDLC panel overlay may be attachable to the glazing using the at least one of the optically clear adhesive and the secondary frame.

[0084] In embodiments, the edge control module may be mounted within a perimeter frame of the glazing.

[0085] In embodiments, a second edge control module may be configured to drive a second PDLC panel overlay. The edge control module may be connectable to the second edge control module, and the edge control module and the second edge control module may distribute the data signal such that the second edge control module drives the second PDLC panel overlay.

[0086] In embodiments, the PDLC panel overlay may be driven according to the method of the first aspect.

[0087] In a sixth aspect, the technique described herein relates to a system for displaying a transparency map using a multi-region selective-opacity panel. The system may include a multi-region selective-opacity panel, one or more processors, and a controller. The multi-region selective-opacity panel may include a plurality of panel regions. The one or more processors may map a transparency map regionof a transparency map to at least one panel region from the plurality of panel regions and may compute a panel-region transparency value in accordance with a transparency value of the transparency map region. The controller may receive control data from the one or more processors, the control data including the panel-region transparency value for the at least one panel region, and may provide an AC drive signal to the at least one panel region in accordance with the panel-region transparency value.

[0088] In embodiments, the transparency map may be an image, and the transparency map region may be an image region, the transparency value being derived from at least one of a transparency channel, an opacity channel, a luminance channel, and / or a grayscale channel of the image.

[0089] In embodiments, the plurality of panel regions may be arranged in a regular grid, the image may be a raster image, the image region may be a pixel of the raster image, and the one or more processors may map the pixel to the regular grid.

[0090] In embodiments, the system may further include a light source. The one or more processors may process the image to obtain one or more intensity channels and a transparency channel and may provide control data to the controller to configure the transparency of the at least one panel region in accordance with the transparency channel. The light source may project light onto the multi-region selective-opacity panel in accordance with the one or more intensity channels under control of the one or more processors.

[0091] In embodiments, the one or more intensity channels may include a color channel, a luminance channel, and / or a chrominance channel.

[0092] In embodiments, the image may be a frame from a video stream, and the one or more processors may be configured to repeat configuring the transparency of the at least one panel region for successive frames of the video stream. Optionally, a frame rate of the video stream may be at least 20 frames per second.

[0093] In embodiments, the multi-region selective-opacity panel may include a Polymer-Dispersed Liquid Crystal (PDLC) panel and the controller may drive the multi-region selective-opacity panel according to the method of the first aspect.

[0094] In embodiments, the system may be configured to provide a view using a multi-region selective-opacity panel. The multi-region selective-opacity panel may include a multi-region selective-opacity panel, one or more processors, and a controller. The multi-region selective-opacity panel may include a plurality of panel regions. The one or more processors may obtain a position of interest relative to the multi-region selective-opacity panel, may render, in a transparency map, a view pattern located relative to the position of interest, the view pattern defining a view region having transparency values greater than those of surrounding regions, may map, in accordance with the view pattern, atransparency map region of the transparency map to at least one panel region, and may provide control data to the controller, the control data including a panel-region transparency value for the at least one panel region in accordance with a transparency value of the transparency map region. The controller may provide an AC drive signal to the at least one panel region in accordance with the panel-region transparency value, thereby creating a view across the multi-region selective-opacity panel.

[0095] In embodiments, the multi-region selective-opacity panel may include a Polymer-Dispersed Liquid Crystal (PDLC) panel.

[0096] In embodiments, the one or more processors may update the transparency map when the position of interest moves.

[0097] In embodiments, the view pattern may have a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person-shaped pattern.

[0098] In embodiments, the position of interest may include a distance relative to the multi-region selective-opacity panel, and the one or more processors may adjust at least one panel region from an at least partially scattering configuration to an at least partially transmissive configuration when the distance of the position of interest is within a distance threshold. Optionally, a size of the view region may be a monotonically decreasing function of the distance of the position of interest. Optionally, transparency within the view region may be a monotonically decreasing function of the distance of the position of interest.

[0099] In embodiments, the position of interest may further include an elevation and the one or more processors may locate the view pattern relative to the elevation.

[0100] In embodiments, the position of interest may be a position of an observer and the view may allow the observer to see through the multi-region selective-opacity panel.

[0101] In embodiments, the one or more processors may obtain a sight direction of the observer and may locate the view pattern relative to an intersection of the sight direction with the multi-region selective-opacity panel.

[0102] In embodiments, the position of interest may be a position of a light source and the view may allow the light source to illuminate through the multi-region selective-opacity panel.

[0103] In embodiments, the position of interest may be a first position of interest located on a first side of the multi-region selective-opacity panel, and the one or more processors may obtain a second position of interest on a second side of the multi-region selective-opacity panel. A line of sight may be computed from the first position of interest to the second position of interest, the line of sight comprising an intersection at the multi-region selective-opacity panel, and the view pattern may be located relative tothe intersection of the line of sight at the multi-region selective-opacity panel. Optionally, the view pattern may be updated when the second position of interest moves.

[0104] In embodiments, the first position of interest may include a first distance relative to the multi-region selective-opacity panel and the second position of interest may include a second distance relative to the multi-region selective-opacity panel. At least one panel region may be adjusted from an at least partially scattering configuration to an at least partially transmissive configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold.

[0105] In embodiments, the system may further include a light source located on a first side of the multi-region selective-opacity panel and configured to project light. The position of interest may be the light source and the view may be used to project an image onto a surface located on a second side of the multi-region selective-opacity panel.

[0106] In embodiments, the system may further include a second multi-region selective-opacity panel. The multi-region selective-opacity panel may be a first multi-region selective-opacity panel and a first view may be configured thereon. A second view may be configured by adjusting a transparency of at least one panel region of the second multi-region selective-opacity panel, thereby allowing an at least partial visibility from the position of interest across the first multi-region selective-opacity panel and the second multi-region selective-opacity panel.

[0107] In embodiments, a second position of interest may be obtained on an opposite side of the second multi-region selective-opacity panel. A line of sight may be computed from the first position of interest towards the second position of interest, the line of sight comprising a first intersection at the first multi-region selective-opacity panel and a second intersection at the second multi-region selective-opacity panel. A first view region may be located relative to the first intersection and a second view region may be located relative to the second intersection, thereby allowing at least partial visibility between the first position of interest and the second position of interest across the first view region and the second view region.

[0108] In embodiments, the first position of interest may be an observer and the second position of interest may be an observee, and the at least partial visibility across the first view region and the second view region may allow the observer to see the observee.

[0109] In embodiments, the multi-region selective-opacity panel may include a PDLC panel and the controller may drive the multi-region selective-opacity panel according to the method of the first aspect.

[0110] In embodiments, the system may be configured to create an obstruction using a multi-region selective-opacity panel. The multi-region selective-opacity panel may include a multi-region selective-opacity panel, one or more processors, and a controller. The multi-region selective-opacity panelmay include a plurality of panel regions. The one or more processors may obtain a position of interest relative to the multi-region selective-opacity panel, may render, in a transparency map, an obstruction pattern located relative to the position of interest, the obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions, may map, in accordance with the obstruction pattern, a transparency map region of the transparency map to at least one panel region, and may provide control data to the controller, the control data including a panel-region transparency value for the at least one panel region in accordance with a transparency value of the transparency map region. The controller may provide an AC drive signal to the at least one panel region in accordance with the panel-region transparency value, thereby creating an obstruction across the multi-region selective-opacity panel.

[0111] In embodiments, the multi-region selective-opacity panel may include a Polymer-Dispersed Liquid Crystal (PDLC) panel.

[0112] In embodiments, the obstruction pattern may be updated when the position of interest moves.

[0113] In embodiments, the obstruction pattern may have a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person-shaped pattern.

[0114] In embodiments, the position of interest may include a distance relative to the multi-region selective-opacity panel, and at least one panel region may be adjusted from an at least partially transmissive configuration to an at least partially scattering configuration when the distance of the position of interest is within a distance threshold. Optionally, a size of the obstruction region may be a monotonically decreasing function of the distance of the position of interest. Optionally, an opacity within the obstruction region may be a monotonically decreasing function of the distance of the position of interest.

[0115] In embodiments, the position of interest may further include an elevation and the obstruction pattern may be located relative to the elevation.

[0116] In embodiments, the position of interest may be a position of an observer and the obstruction may prevent the observer from seeing, at least partially, through the multi-region selective-opacity panel.

[0117] In embodiments, a sight direction of the observer may be obtained and the obstruction pattern may be located relative to an intersection of the sight direction with the multi-region selective-opacity panel.

[0118] In embodiments, the position of interest may be a position of a light source and the obstruction may prevent the light source from illuminating, at least partially, through the multi-region selective-opacity panel.

[0119] In embodiments, the position of interest may be a first position of interest located on a first side of the multi-region selective-opacity panel, a second position of interest may be obtained on a secondside of the multi-region selective-opacity panel, and a line of sight may be computed from the first position of interest to the second position of interest, the line of sight comprising an intersection at the multi-region selective-opacity panel. The obstruction pattern may be located relative to the intersection of the line of sight at the multi-region selective-opacity panel. Optionally, the obstruction pattern may be updated when the second position of interest moves.

[0120] In embodiments, the first position of interest may include a first distance relative to the multi-region selective-opacity panel and the second position of interest may include a second distance relative to the multi-region selective-opacity panel, and at least one panel region may be adjusted from an at least partially transmissive configuration to an at least partially scattering configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold.

[0121] In embodiments, the position of interest may be a light source located on a first side of the multi-region selective-opacity panel, and the obstruction region may be used to project a shadow onto a surface located on a second side of the multi-region selective-opacity panel.

[0122] In embodiments, the system may further include a second multi-region selective-opacity panel. The multi-region selective-opacity panel may be a first multi-region selective-opacity panel and a first obstruction may be configured thereon. A second obstruction pattern may be rendered by adjusting a transparency of at least one panel region of the second multi-region selective-opacity panel, thereby preventing complete visibility from the position of interest across the first multi-region selective-opacity panel and the second multi-region selective-opacity panel.

[0123] In embodiments, the position of interest may be a first position of interest and a second position of interest may be obtained on an opposite side of the second multi-region selective-opacity panel. A line of sight from the first position of interest towards the second position of interest may be computed, the line of sight comprising a first intersection at the first multi-region selective-opacity panel and a second intersection at the second multi-region selective-opacity panel. A first obstruction region may be located relative to the first intersection and a second obstruction region may be located relative to the second intersection, thereby preventing complete visibility between the first position of interest and the second position of interest across the first obstruction region and the second obstruction region.

[0124] In embodiments, the first position of interest may be an observer and the second position of interest may be an observee, and preventing complete visibility across the first obstruction region and the second obstruction region may prevent the observer from seeing the observee.

[0125] In embodiments, the multi-region selective-opacity panel may include a PDLC panel and the controller may drive the multi-region selective-opacity panel according to the method of the first aspect.BRIEF DESCRIPTION OF THE DRAWINGS

[0126] Further features and exemplary advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the appended drawings, in which:

[0127] Figure 1 is an activity diagram of an exemplary method for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel in accordance with the teachings of the present invention;

[0128] Figure 2 is an activity diagram of an exemplary method for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel using phase-shifted AC signals in adjacent PDLC regions in accordance with the teachings of the present invention;

[0129] Figure 3 is an activity diagram of an exemplary method for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel using an opacity response curve to modulate an AC drive signal (including PWM gating and optional low-pass filtering), in accordance with the teachings of the present invention;

[0130] Figure 4 is an activity diagram of an exemplary method for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel using region-addressable control, wherein region identifiers and a configuration stream enable a region controller to modulate AC drive signals per region configuration, in accordance with the teachings of the present invention;

[0131] Figure 5 is an activity diagram of an exemplary method for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel incorporating pre-manufacture steps, including isolating PDLC regions within a transparent conductive coating and connecting a PDLC region to a region controller, in accordance with the teachings of the present invention;

[0132] Figure 6 is an activity diagram of an exemplary method for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel incorporating manufacturing steps in which a transparent conductive coating is patterned to form isolation channels (optionally by laser ablation and lamination) prior to connecting a PDLC region to a region controller, in accordance with the teachings of the present invention;

[0133] Figure 7 is an activity diagram of an exemplary method for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel incorporating a multi-layer routing approach in which a second transparent conductive layer provides perimeter-to-interior conductive traces with laminated dielectric isolation and conductive interconnects to selected PDLC regions, in accordance with the teachings of the present invention;

[0134] Figure 8 is an activity diagram of an exemplary method for retrofitting a glazing with a PDLC panel overlay, including attachment to the glazing, connection to an edge control module, and driving via AC power and a data signal from an external control module, in accordance with the teachings of the present invention;

[0135] Figure 9 is an activity diagram of an exemplary method for retrofitting a glazing with a PDLC panel overlay, illustrating attachment via optically clear adhesive or a secondary frame, and subsequent connection and driving via an edge control module, in accordance with the teachings of the present invention;

[0136] Figure 10 is an activity diagram of an exemplary method for retrofitting a glazing with a PDLC panel overlay, further showing daisy-chained edge control modules to drive a second PDLC panel overlay in response to a distributed data signal, in accordance with the teachings of the present invention;

[0137] Figure 11 is an activity diagram of an exemplary method for displaying an image using a multi-region selective-opacity panel, including mapping image regions to panel regions and configuring regional transparency accordingly, in accordance with the teachings of the present invention;

[0138] Figure 12 is an activity diagram of an exemplary method for displaying an image using a multi-region selective-opacity panel, illustrating processing into intensity and transparency channels, configuring regional transparency per the transparency channel, and projecting light per the intensity channels, in accordance with the teachings of the present invention;

[0139] Figure 13 is an activity diagram of an exemplary method for displaying video on a multi-region selective-opacity panel, illustrating per-frame mapping and transparency configuration with intensity / transparency channel processing and light projection repeated for successive frames, in accordance with the teachings of the present invention;

[0140] Figure 14 is an activity diagram of an exemplary method for providing a view using a multi-region selective-opacity panel, including configuring regional transparency based on a position of interest (with optional updates upon movement), in accordance with the teachings of the present invention;

[0141] Figure 15 is an activity diagram of an exemplary method for providing a view using a multi-region selective-opacity panel located at the intersection of an observer's sight direction with the panel, in accordance with the teachings of the present invention;

[0142] Figure 16 is an activity diagram of an exemplary method for providing a view aligned to a computed line of sight between positions on opposite sides of a multi-region selective-opacity panel, in accordance with the teachings of the present invention;

[0143] Figure 17 is an activity diagram of an exemplary method for providing a view when first and second distances of positions of interest are within respective thresholds, in accordance with the teachings of the present invention;

[0144] Figure 18 is an activity diagram of an exemplary method providing coordinated views across two multi-region selective-opacity panels, in accordance with the teachings of the present invention;

[0145] Figure 19 is an activity diagram of an exemplary method providing aligned views across two multi-region selective-opacity panels based on a computed line of sight between positions on opposite sides, in accordance with the teachings of the present invention;

[0146] Figure 20 is an activity diagram of an exemplary method for obstructing a view by adjusting regional opacity of a multi-region selective-opacity panel based on a position of interest, in accordance with the teachings of the present invention;

[0147] Figure 21 is an activity diagram of an exemplary method for obstructing a view at the intersection of an observer's sight direction with a multi-region selective-opacity panel, in accordance with the teachings of the present invention;

[0148] Figure 22 is an activity diagram of an exemplary method for obstructing a view aligned to a computed line of sight between positions on opposite sides of a multi-region selective-opacity panel, in accordance with the teachings of the present invention;

[0149] Figure 23 is an activity diagram of an exemplary method providing coordinated obstructions across two multi-region selective-opacity panels, in accordance with the teachings of the present invention;

[0150] Figure 24 is an activity diagram of an exemplary method providing aligned obstructions across two multi-region selective-opacity panels based on a computed line of sight between positions on opposite sides, in accordance with the teachings of the present invention;

[0151] Figure 25 is a block diagram of an exemplary Polymer-Dispersed Liquid Crystal (PDLC) system in accordance with the teachings of the present invention;

[0152] Figure 26 is a block diagram of an exemplary Polymer-Dispersed Liquid Crystal (PDLC) retrofit system in accordance with the teachings of the present invention;

[0153] Figure 27 is a block diagram of an exemplary Polymer-Dispersed Liquid Crystal (PDLC) retrofit system used with daisy chaining in accordance with the teachings of the present invention;

[0154] Figure 28 is a block diagram of an exemplary system for displaying a transparency map using a multi-region selective-opacity panel, in accordance with the teachings of the present invention;

[0155] Figure 29 is a drawing of an exemplary system for displaying an image using a multi-region selective-opacity panel used to display an image on a window face of a building, in accordance with the teachings of the present invention;

[0156] Figure 30 is a drawing of an exemplary system for displaying an image using a multi-region selective-opacity panel used to display an image in combination with a light source, in accordance with the teachings of the present invention;

[0157] Figure 31 is a drawing of an exemplary system for displaying an image using a multi-region selective-opacity panel used to display an image in combination with a light source to create shadows, in accordance with the teachings of the present invention;

[0158] Figure 32 is a drawing of an exemplary system for displaying an image using a multi-region selective-opacity panel used for signage, in accordance with the teachings of the present invention;

[0159] Figure 33 is a drawing of an exemplary system for providing a view using a multi-region selective-opacity panel used to provide visibility between an observer and an observee, in accordance with the teachings of the present invention;

[0160] Figure 34 is a drawing of an exemplary system for obstructing a view using a multi-region selective-opacity panel used to cast a shadow on a specific location, in accordance with the teachings of the present invention;

[0161] Figure 35 is a grid illustrating an exemplary arrangement for adjacent PDLC regions phase distributions, in accordance with the teachings of the present invention;

[0162] Figure 36 is a picture of an exemplary flexible Printed Circuit Board (PCB) in accordance with the teachings of the present invention; and

[0163] Figure 37 is a picture of an exemplary flexible Printed Circuit Board (PCB) in accordance with the teachings of the present invention.DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0164] The teachings presented herein may be applied across a comprehensive range of indoor and outdoor applications. Techniques for refreshing, reducing interference, shading, configuring, dividing, displaying images, providing views, and obstructing views using a Polymer-Dispersed Liquid Crystal (PDLC) panel 100 may be implemented in integrated glazing and / or as retrofittable overlays, and may be adapted to panels of various sizes, shapes, and subdivisions into regions.

[0165] Indoor applications may include, without limitation, office partitions and meeting room enclosures that may provide on-demand privacy and distraction reduction, storefronts and display cases that may switch between transparent presentation and dynamic display, and museum or gallery installations that may modulate visibility for presentation and protection of exhibits.

[0166] Outdoor and building-envelope applications may include fagades, pavilions, canopies, and greenhouses where light transmission and shading may be modulated to improve comfort, energy performance, or aesthetics. Transportation and public-space applications may include windows, shelters, and signage where content and privacy may be dynamically adjusted. The panel may be integrated intocanopies or awnings to provide dynamic shading, signage, and night-time projection while preserving daylighting control.

[0167] Further adaptations may include dynamic shading for residential or commercial buildings, privacy-enhancing windows for healthcare or hospitality, and adaptive transparency for vehicles (e.g., cars, trains, marine vessels, aircraft). In such embodiments, the PDLC panel 100 may be integrated as original equipment or provided as a PDLC panel overlay for retrofit.

[0168] In embodiments, transparency may be configured in accordance with a transparency map whose regions may be mapped to panel regions 110. The transparency map may be derived from an image and / or may be rendered procedurally to include, for example, patterns configured to provide a view and / or to create an obstruction. Configuration may be static or may be dynamically updated over time.

[0169] A PDLC panel 100 may be configured as a multi-region panel whose regions 110 are addressable individually and / or in groups. Drive signals may include alternating current (AC) waveforms provided to at least one region 110. In embodiments, adjacent regions may be driven with phase-shifted AC signals having a common frequency, and an effective voltage may be modulated in accordance with a response characteristic of a region 110.

[0170] One or more processors 600 may compute control data comprising panel-region transparency values for at least one panel region 110, and a controller 200 may provide AC drive signals to the at least one panel region 110 in accordance with the panel-region transparency values. Communication and addressing may be provided via a configuration stream, and region controllers 220 may modulate drive signals according to a received region configuration. The particular hardware realization may vary and does not limit the disclosed methods and systems.

[0171] Configured as a retrofit, a PDLC panel overlay 100 may be attached to an exposed surface of a glazing 20 and connected via an interconnect bus 160 to an edge control module 300, which may receive AC power and a data signal from an external control module 350. Multiple overlays may be driven in a daisy-chain arrangement of edge control modules 300 / 300'.

[0172] In embodiments, PDLC panels 100 may be manufactured with transparent conductive coatings patterned to define a plurality of PDLC regions 110. Additional transparent conductive layers may be employed to route conductive traces toward interior locations, with electrically conductive interconnects at registered contact points. Lamination, dielectric interlayers, and interconnect techniques may be selected to satisfy electrical isolation, environmental sealing, and mechanical robustness.

[0173] Safety and regulatory considerations may include provision of a ground connection 122 to a ground conductive coating at a back side 116 of a region 110, electrical isolation and creepage / clearanceat panel perimeters, overcurrent and electrostatic discharge protection in control electronics, and environmental sealing appropriate for the intended installation.

[0174] A first aspect of the techniques described herein relates to a Polymer-Dispersed Liquid Crystal (PDLC) panel 100. Reference is now made to the drawings in which the activity diagram of Figure 1 depicts an exemplary method 1000 for driving a PDLC panel 100, and the block diagram of Figure 25 depicts an exemplary Polymer-Dispersed Liquid Crystal (PDLC) system 5000 that may implement the method 1000.

[0175] A PDLC panel 100 may include liquid crystal droplets dispersed within a polymer matrix between transparent conductive coatings. The PDLC panel 100 may be engineered to change optical properties, such as transparency and opacity, in response to an applied electrical voltage. When no voltage is applied, the liquid crystal droplets may scatter light, causing the PDLC panel 100 to appear at least partially scattering (opaque or translucent). When an electrical voltage is applied, the liquid crystal droplets may align to allow light to pass through, thereby rendering the PDLC panel 100 at least partially transmissive. Reverse-mode implementations may also be used, wherein the default is at least partially transmissive and application of voltage may increase scattering; the techniques herein may be adapted accordingly.

[0176] The PDLC panel 100 may be subdivided into a plurality of PDLC regions 110 that may be independently driven to change optical properties locally. Each PDLC region 110 may be electrically isolated from neighboring PDLC regions 110 and may be controlled separately or in groups to achieve localized transparency or opacity effects. Region size and arrangement may be selected according to application constraints without limiting the method 1000.

[0177] At a PDLC region 110 of the PDLC panel 100, a back side 116 of the PDLC region 110 may be grounded 1110 to a ground connection 122. Grounding 1110 the back side 116, for example via a ground conductive coating connected to the ground connection 122, may stabilize an electrical potential of the PDLC region 110 and facilitate controlled transitions between transparency states.

[0178] The term "ground connection” as used herein refers to the driver's reference potential for the PDLC stack and need not be protective earth. In isolated or SELV implementations, the ground connection may be a local reference node to which the back-side conductive coating is referenced and to which active discharge is effected by the draining gate.

[0179] A voltage may be applied 1120 to a front side 112 of the PDLC region 110 via a first gate 114, causing the PDLC region 110 to accumulate a charge and transition into a first transparency state. The charge may be drained 1130 from the front side 112 of the PDLC region 110 via a second gate 118 subsequent to interrupting the voltage via the first gate 114, causing the PDLC region 110 to transition intoa second transparency state. One of the first transparency state and the second transparency state may be an at least partially transmissive state and the other may be an at least partially scattering state. The PDLC region 110 may transition into the second transparency state within 50 ms after the second gate 118 is closed.

[0180] The first gate 114 and the second gate 118 may form a half-bridge between a supply rail and the ground connection 122, a switching node of the half-bridge being electrically coupled to the front side 112 of the PDLC region 110 (e.g., to an input conductive coating on the front side 112). During a charging phase, the first gate 114 may be closed and the second gate 118 may be open, thereby applying a voltage at the switching node to the front side 112 such that liquid crystal droplets within the PDLC region 110 align and the PDLC region 110 is at least partially transmissive. During a draining phase, the first gate 114 may be open and the second gate 118 may be closed, thereby connecting the front side 112 to the ground connection 122 and allowing stored charge to drain so that the PDLC region 110 becomes at least partially scattering. The applied voltage may comprise an alternating-current (AC) signal; further examples of drive signal generation and modulation are provided in subsequent sections.

[0181] The PDLC region 110 may transition into the second transparency state within 50 ms after closing the second gate 118. Passive implementations that rely on natural dissipation of charge on the front side 112 may exhibit slower transitions, whereas actively draining 1130 charge from the front side 112 via the second gate 118 subsequent to interrupting the voltage via the first gate 114 may reduce residual electric field and accelerate the transition to the second transparency state. In some embodiments, transition within 40 ms may be achieved; in further embodiments, within 30 ms; and in still further embodiments, within about 20-25 ms, subject to material formulation, panel thickness, drive amplitude / frequency, temperature, and region geometry.

[0182] Such reductions in transition time may enable dynamic applications, for example refreshing at rates suitable for animated content or interactive effects. By way of non-limiting illustration, a transition within 50 ms may support updates at or above 20 frames per second; within 33 ms may support about 30 frames per second; and within 16.7 ms may support about 60 frames per second in favorable operating conditions. T ransition time may include contributions from both electrical discharge and material relaxation; actively draining via the second gate 118 may reduce the electrical contribution, while selection of PDLC material properties and cell thickness may influence the relaxation component. Discharge path impedance, panel capacitance per region, and ambient temperature may be selected or controlled to meet a target transition time without exceeding supply limits or thermal constraints.

[0183] The first gate 114 and the second gate 118 may form a half-bridge between a supply rail and the ground connection 122, a switching node of the half-bridge being electrically coupled to the front side 112 of the PDLC region 110, for example to an input conductive coating on the front side 112. In operation,the first gate 114 may be selectively closed to drive the switching node toward the supply rail during a charging phase, and the second gate 118 may be selectively closed to connect the switching node to the ground connection 122 during a draining phase. Non-overlap (dead-time) between the turn-off of one gate and the turn-on of the other may be provided to reduce shoot-through current. The half-bridge may be implemented using, for example, field-effect transistors (e.g., MOSFETs) arranged as high-side / low-side switches with appropriate gate-drive circuitry (e.g., level shifting and / or bootstrap for the high-side device), or using other solid-state switching devices having suitable voltage and current ratings. A series impedance (e.g., a small resistor) may be included between the switching node and the front side 112 to manage inrush and ringing, and over-voltage / over-current protection may be provided to meet safety and reliability constraints.

[0184] The voltage applied to the front side 112 may include an alternating-current (AC) signal. The AC signal may be substantially zero-mean to reduce ionic migration and long-term charge accumulation in the PDLC stack, and may take a variety of waveforms, including sinusoidal, square, trapezoidal, and / or PWM-shaped waveforms. A common drive frequency may be selected based on optical performance and comfort (e.g., to mitigate flicker), for example in a range of about 40 Hz to about 200 Hz, optionally about 60 Hz to about 120 Hz. An effective amplitude (e.g., Vrms) may be selected to achieve a target transparency while observing dielectric and safety limits; by way of non-limiting example, amplitudes may be produced from one or more DC rails whose magnitudes are below about ±57 V. Effective voltage at the front side 112 may be further modulated in accordance with a region response characteristic (e.g., using PWM gating of the AC waveform with a carrier in the kHz range) to obtain intermediate transparency levels. Phase-shifted AC signals across adjacent regions may be used in other embodiments described herein; however, the use of an AC signal at the front side 112 does not require phase shifting and may be implemented independently.

[0185] As used herein, "adjacent PDLC regions” means PDLC regions that share a common boundary in the panel layout. Assigning distinct phase relationships to adjacent regions may reduce simultaneous boundary potential differences, moderates aggregate instantaneous current, and mitigates fringe-field crosstalk and visible artifacts at region edges.

[0186] Reference is now made to the drawings in which Figure 2 depicts an exemplary method 1000 for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel 100 using phase-shifted AC signals in adjacent PDLC regions 110. Adjacent PDLC regions 110 may influence one another through fringe-fields and capacitive coupling when driven at different instantaneous potentials, which may manifest as crosstalk or blurred boundaries. Driving immediately adjacent regions 110 with controlled phase relationships and providing a common ground reference may mitigate such interference.

[0187] The PDLC panel 100 may be a multi-region PDLC panel. The back side 116 of each of two or more adjacent PDLC regions 110 may be grounded 1210 to the ground connection 122. Two or more phase-shifted alternating-current (AC) signals may be generated 1220 with a common frequency. The two or more phase-shifted AC signals may be respectively distributed 1230 to respective front sides 112 of the two or more adjacent PDLC regions 110. Optionally, the phase-shifted AC signals may be uniformly phase-spaced from one another. Optionally, the common frequency may be between 60 Hz and 120 Hz.

[0188] Driving adjacent PDLC regions 110 with phase-shifted alternating-current (AC) signals having a common frequency may reduce interference therebetween, including supply-ripple-induced luminance variation, conducted or radiated electromagnetic emissions (EMI), and inter-region electrical coupling artifacts (including fringe-field and capacitive crosstalk).

[0189] Generating 1220 two or more phase-shifted AC signals having a common frequency may be performed in a variety of ways without limitation. For example, a multi-output oscillator may provide inherently phase-displaced outputs at the common frequency; a single-frequency source may be combined with phase-splitting or delay networks to realize target phase offsets; or synchronized output channels may be produced under digital control relative to a shared timing reference. Amplitude matching and timing synchronization among outputs may be maintained so that the common frequency and relative phases remain stable over time. By way of example, three outputs may be spaced by 120 degrees; four outputs by 90 degrees; or five outputs by 72 degrees. Figure 35 depicts an exemplary arrangement of phase distributions for adjacent PDLC regions 110 suitable for a five-phase pattern.

[0190] The phase-shifted AC signals generated at 1220 may be distributed 1230 so that each signal is applied to the input conductive coating at the front side 112 of a corresponding immediately adjacent PDLC region 110. Driving neighboring regions out of phase at a common frequency may reduce instantaneous potential differences across shared boundaries and may limit mutual field influence, thereby improving uniformity of perceived transparency transitions at region edges.

[0191] Generating 1220 the two or more phase-shifted AC signals may include alternating 1225 between a positive direct-current (DC) supply and a negative DC supply, thereby balancing a load of the two or more phase-shifted AC signals across the positive DC supply and the negative DC supply. Optionally, the positive DC supply may be less than 57 volts and the negative DC supply may be greater than -57 volts. In further embodiments, the common frequency may be selected within a broader range suitable for optical performance and comfort (e.g., to mitigate perceptible flicker), and the number of phases may be selected according to panel geometry and cabling constraints.

[0192] The two or more phase-shifted AC signals may be uniformly phase-spaced from one another. For N channels, uniform spacing may correspond to phase offsets of approximately 360° / N (e.g., 180° fortwo channels, 120° for three channels, 90° for four channels, 72° for five channels). Uniform spacing may reduce simultaneous peak demand across channels and may improve boundary uniformity among adjacent PDLC regions 110.

[0193] Generating 1220 the two or more phase-shifted AC signals may include alternating 1225 between a positive direct-current (DC) supply and a negative DC supply so that each channel is synthesized as a substantially zero-mean bipolar AC waveform. Interleaving phases across channels while alternately sourcing from the positive and negative rails may balance load across the rails over time, which may reduce supply ripple and thermal stress and may facilitate compact power conversion.

[0194] The positive DC supply may be less than 57 volts and the negative DC supply may be greater than -57 volts. By way of non-limiting example, rails may be provided at approximately ±48 V or ±36 V, with the front side 112 of a PDLC region 110 being driven between the positive and negative rails under half-bridge control to produce the desired bipolar AC waveform. Selection of rail magnitudes and waveform shape (e.g., sinusoidal, square, PWM-gated) may be made to achieve the target effective voltage at the PDLC region while satisfying safety, insulation, and optical-performance constraints. In some embodiments tailored for lower-voltage operation (e.g., specific PDLC formulations and cell thicknesses), acceptable transparency modulation may be obtained with effective voltages at or below about 36 Vrms; in other embodiments, higher effective voltages within typical PDLC ranges may be selected.

[0195] Reference is now made to the drawings in which Figure 3 depicts an exemplary method 1000 for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel 100 using an opacity response curve to modulate an AC drive signal, with optional PWM gating and low-pass filtering.

[0196] An opacity response curve of the PDLC region 110 may be obtained 1310. The opacity response curve may relate a measure of optical state (e.g., transmittance, opacity, or haze) to an effective drive parameter (e.g., Vrms at a selected AC frequency). The curve may be determined by applying a set of calibrated AC drive conditions to the PDLC region 110 while grounding 1110 its back side 116 to a ground connection 122, and measuring the resulting optical response. The curve may be established per panel type, per batch, or per region 110, and may optionally include temperature compensation and / or account for hysteresis between increasing and decreasing drive levels. The response may be stored, for example, as a lookup table or parametric model for use during drive.

[0197] An alternating current (AC) signal may be provided 1330 to a front side 112 of the PDLC region 110, for example to an input conductive coating on the front side 112. The AC signal may be substantially zero-mean and may use a frequency selected for optical performance and comfort (e.g., to mitigate perceptible flicker). The AC signal may be modulated 1340 according to the opacity responsecurve so that an effective drive (e.g., Vrms) delivered to the PDLC region 110 corresponds to a target transparency or opacity.

[0198] The AC signal may be interrupted 1342 according to a Pulse- Width Modulation (PWM) signal to generate a PWM-modulated AC signal. PWM gating may be applied within or across AC cycles such that the duty cycle determines the effective voltage delivered to the PDLC region 110 while maintaining a zero-mean waveform to limit ionic migration. The PWM carrier frequency may be selected sufficiently higher than the AC frequency to avoid visible artifacts, for example in a range of about 1 kHz to about 100 kHz, optionally about 5 kHz to about 50 kHz, with duty-cycle limits selected to maintain control linearity (e.g., about 5% to about 95%). Gating may be applied symmetrically over positive and negative half-cycles to preserve DC balance.

[0199] The PWM-modulated AC signal may be filtered 1344 with a low-pass filter. The low-pass filter may attenuate PWM carrier components while passing the AC fundamental, thereby smoothing the effective drive seen at the front side 112. The filter may be implemented, for example, as an RC, RL, or LC network with a cutoff frequency selected above the AC frequency and well below the PWM carrier (e.g., a cutoff a few times the AC frequency) to reduce ripple and acoustic / EMI emissions while preserving the intended AC excitation. In some embodiments, snubbers or damping elements may be provided to manage switching transients and ringing. The combination of PWM gating and low-pass filtering may provide fine control over intermediate transparency levels while maintaining a zero-mean AC drive consistent with PDLC material reliability.

[0200] Reference is now made to the drawings in which Figure 4 depicts an exemplary method 1000 using region-addressable control, wherein region identifiers and a configuration stream enable a region controller to modulate AC drive signals per region configuration.

[0201] The PDLC panel 100 may be a multi-region PDLC panel. A region identifier may be assigned 1410 to a PDLC region 110 of the multi-region PDLC panel 100. The region identifier may uniquely reference the PDLC region 110 and may be encoded, for example, as a numeric index, an alphanumeric code, a row-column coordinate, or a hierarchical address (e.g., panel:row:column). Region identifiers may be static (pre-assigned) or may be discovered / configured during commissioning.

[0202] A configuration stream comprising the region identifier and a region configuration may be received 1420. The configuration stream may carry, for each addressed region identifier, at least one parameter indicative of a target optical state (e.g., a target transparency / opacity level), and may optionally include additional parameters such as a transition time, a modulation profile, and / or a priority flag. The configuration stream may be a Digital Multiplex (DMX) data stream. Alternative transports and protocols may be used, including RS-485 / Modbus, CAN, Ethernet-carried protocols (e.g., Art-Net,sACN / DMX-over-IP, UDP / TCP), and / or other wired or wireless industrial / building-automation links, provided that addressing of region identifiers and delivery of region configurations are maintained.

[0203] An alternating-current (AC) signal may be modulated 1430 according to the region configuration via a region controller 220 configured to drive the PDLC region 110 corresponding to the region identifier. Modulating 1430 the AC signal may include adjusting at least one of: an effective amplitude (e.g., Vrms), a duty cycle of PWM gating applied to an AC waveform, a phase selection in a multi-phase drive scheme, and / or a time-varying ramp consistent with a requested transition time. The modulated AC signal may be applied to an input conductive coating at a front side 112 of the PDLC region 110 while a back side 116 is grounded to a ground connection 122, thereby configuring the transparency of the PDLC region 110 in accordance with the region configuration.

[0204] By way of non-limiting example in a DMX embodiment, a multi-region PDLC panel 100 with N regions 110 may be assigned a DMX start channel S. Each region identifier k (0 < k < N) may map to M consecutive DMX channels, so that channels S + k'M through S + k'M + (M - 1) carry the region configuration for region k. With M = 1 , an 8-bit value (0-255) may encode the target transparency level; with M = 2, a second 8-bit value may encode a transition time or curve (e.g., immediate, linear fade, or eased profile). The region controller 220 may translate the received value(s) into a modulation of the AC signal 1430 consistent with the opacity response of the PDLC region 110. Multiple panels may share a common configuration stream by allocating non-overlapping address spaces (e.g., disjoint DMX channel ranges) while forwarding the stream downstream; only messages containing matching panel and / or region identifiers need be acted upon locally.

[0205] In further embodiments, addressing may include group identifiers in addition to individual region identifiers so that a region controller 220 may apply a common region configuration to a set of PDLC regions 110 for coordinated effects. Optional error-checking and sequencing (e.g., checksums, sequence numbers) may be used to ensure reliable application of region configurations without constraining the underlying transport.

[0206] Reference is now made to the drawings in which Figure 5 depicts an exemplary method 1000 incorporating pre-manufacture steps, including isolating PDLC regions within a transparent conductive coating and connecting a PDLC region to a region controller, and in which Figure 6 depicts an exemplary method 1000 incorporating manufacturing steps in which a transparent conductive coating is patterned to form isolation channels (optionally by laser ablation and lamination) prior to connecting a PDLC region to a region controller.

[0207] Prior to driving the PDLC panel 100, a plurality of PDLC regions 110 may be isolated 1510 within a transparent conductive coating of the PDLC panel 100, for example within an input conductivecoating at a front side 112. At least one PDLC region 110 of the plurality of PDLC regions 110 may be connected 1520 to a region controller 220 configured to drive the at least one PDLC region 110.

[0208] Isolating 1510 the PDLC regions 110 may include providing 1512 a substrate carrying a transparent conductive coating at the front side 112 and patterning 1514 the transparent conductive coating to form isolation channels in the transparent conductive coating. Optionally, the transparent conductive coating may be ablated 1516 using a laser prior to lamination to a PDLC layer. The patterned substrate may be laminated 1518 to a PDLC layer, thereby defining the plurality of PDLC regions 110. Patterning 1514 may be performed using one or more of laser ablation, wet or dry etching (with masking), mechanical scribing, or lift-off processes, provided that adjacent PDLC regions 110 are electrically isolated to enable independent drive.

[0209] The transparent conductive coating may include indium tin oxide (ITO), for example deposited on a polymeric substrate. Other transparent conductors may be used, including fluorine-doped tin oxide (FTO) and aluminum-doped zinc oxide (AZO), selected according to optical transmission, sheet resistance, and mechanical requirements. The isolation channels may have a width less than 100 pm and the ITO sheet resistance may be between 10 Q / sq and 200 Q / sq. In further embodiments, isolation channel widths may be within about 20-60 pm to reduce inactive area, and sheet resistance may be selected to balance lateral voltage uniformity within a PDLC region 110 against optical losses. Channel depth and sidewall quality may be controlled to ensure complete electrical separation with minimal edge roughness observable in the finished panel.

[0210] Connecting 1520 the at least one PDLC region 110 to a region controller 220 may include providing an electrical interconnect from the input conductive coating at the front side 112 of the selected PDLC region 110 to the region controller 220, and providing a return / ground connection from a ground conductive coating at a back side 116 to a ground connection 122. Interconnect technologies may include, for example, edge bonding to patterned contact pads, use of anisotropic conductive films, or other fine-pitch interconnects compatible with the chosen substrate and conductor stack. Additional embodiments in which conductive traces are routed from a panel perimeter toward interior locations using an additional transparent conductive layer are described hereinbelow with reference to Figure 7.

[0211] In further embodiments, PDLC region isolation may be augmented or implemented by patterned dielectric barriers deposited over portions of the input conductive coating, or by micro-structuring techniques (e.g., laser micromachining or photolithography) that produce grooves or barrier features to limit lateral conduction and fringe-field coupling between adjacent PDLC regions 110. Conductive and / or dielectric features may also be deposited by print processes (e.g., screen or inkjet) compatible with the substrate and coating materials, provided that optical clarity and electrical isolation targets are met.

[0212] Reference is now made to the drawings in which Figure 7 depicts an exemplary method 1000 incorporating a multi-layer routing approach in which a second transparent conductive layer provides perimeter-to-interior conductive traces with laminated dielectric isolation and conductive interconnects to selected PDLC regions 110.

[0213] Prior to driving the PDLC panel 100, a second substrate carrying a transparent conductive coating may be provided 1530. The transparent conductive coating of the second substrate may be patterned 1532 to form conductive traces routed from a perimeter of the PDLC panel 100 toward interior locations. The second substrate and a PDLC layer may be laminated 1534 with a dielectric interlayer therebetween. Conductive interconnects may be formed 1536 between the conductive traces and input conductive coatings of selected PDLC regions 110. The conductive interconnects may be provided at registered contact points, for example by selectively opening the dielectric interlayer at locations aligned to the input conductive coatings and forming a conductive path using one or more of anisotropic conductive film (ACF), conductive epoxy, plated-through microvias, or deposited metallic bumps, thereby establishing low-resistance connections without compromising optical clarity.

[0214] The second substrate may include a transparent conductive coating such as indium tin oxide (ITO) disposed on glass and / or on a polymeric substrate (e.g., PET). Patterning 1532 may be achieved via laser ablation, wet or dry etching with masking, or lift-off, to define traces whose widths and spacings are selected to satisfy both optical and electrical requirements. Traces may be routed to interior PDLC regions 110 that do not adjoin a panel perimeter, while minimizing visual impact. Registration tolerances may be maintained so that each trace terminates at a corresponding registered contact point over the input conductive coating of a selected PDLC region 110. The dielectric interlayer laminated at 1534 may provide electrical isolation between the trace layer and the PDLC layer, except at the registered contact points opened for the conductive interconnects 1536.

[0215] In further embodiments, additional transparent conductive layers may be employed to provide overlapping routing on different planes, with each additional layer laminated with dielectric isolation and interconnected at selected registered contact points. For example, a primary transparent conductive layer may be patterned to define the plurality of PDLC regions 110, and an additional transparent conductive layer on a second substrate may be patterned to form conductive traces extending from the panel perimeter toward interior PDLC regions 110. Layer thicknesses, sheet resistances, and optical transmission may be selected to balance routing conductivity with overall panel transparency.

[0216] The at least one PDLC region 110 may be connected 1520 using a flexible printed circuit board (PCB) 160. The flexible PCB 160 may be bonded to contact pads using an anisotropic conductive film (ACF) to establish electrical connection to the input conductive coatings and / or to the ground conductive coating. Optionally, the flexible PCB 160 and a region controller 220 may be embedded withina perimeter frame of the PDLC panel 100, thereby reducing visible wiring and providing mechanical protection. Flexible interconnects may facilitate conformal routing around panel edges and may improve robustness under handling and thermal cycling. In such embodiments, the flexible PCB 160 may distribute a power source 120, a ground connection 122, and control signals to respective PDLC regions 110 while presenting a compact connector interface to external electronics.

[0217] In another embodiment, the flexible PCB 160 may be configured to connect each PDLC region 110 to a corresponding region controller 220 for independent control of transparency of each PDLC region 110. The flexible PCB 160 and a plurality of region controllers 220 may be embedded within a frame of the PDLC panel 100, optionally together with connectors for AC power and a configuration stream. Bonding the flexible PCB 160 to the panel contact pads using ACF may avoid localized heating at the transparent conductive coating and may provide fine-pitch connections compatible with patterned ITO.

[0218] Reference is now made to the drawings in which the activity diagram of Figure 8 depicts an exemplary method 2000 for retrofitting a glazing 20 with a PDLC panel overlay 100, including attachment to the glazing, connection to an edge control module, and driving via AC power and a data signal from an external control module. Reference is also made to the drawings in which the block diagram of Figure 26 depicts an exemplary Polymer-Dispersed Liquid Crystal (PDLC) retrofit system 6000 in accordance with the teachings of the present invention.

[0219] A second aspect of the techniques described herein relates to a method 2000 for retrofitting a glazing 20 with a multi-region Polymer-Dispersed Liquid Crystal (PDLC) panel overlay. Retrofitting may be useful where an existing glazing 20 is to be augmented without removal or replacement, thereby reducing installation cost and downtime associated with full reglazing. The PDLC panel overlay 100 may be attachable using an optically clear adhesive and / or a secondary frame retained within a window reveal of the glazing 20, thereby limiting invasive work on the building envelope or fixture. Mounting an edge control module 300 within a perimeter frame of the glazing 20 and using an interconnect bus 160 along at least one edge of the PDLC panel overlay 100 may facilitate service access at the perimeter, thereby simplifying maintenance without disturbing the glazing 20. A modular arrangement in which the interconnect bus 160 is connectable to the edge control module 300, the edge control module 300 is connectable to a second edge control module 300' configured to drive a second PDLC panel overlay 100', and an external control module 350 supplies alternating current (AC) power and a data signal may allow field replacement of a PDLC panel overlay 100 or an edge control module 300 independently of the glazing 20.

[0220] A PDLC panel overlay 100 comprising a plurality of PDLC regions 110, an interconnect bus 160 along at least one edge of the PDLC panel overlay 100, and electrical coupling between the interconnect bus 160 and an input conductive coating of the plurality of PDLC regions 110 may be attached2010 to an exposed surface of the glazing 20. The PDLC panel overlay 100 may be a thin laminated construct incorporating a liquid crystal-polymer matrix subdivided into the plurality of PDLC regions 110, where each PDLC region 110 may include an input conductive coating at a front side 112 and a cooperating opposing conductive layer at a back side 116 to establish an electric field across the PDLC region 110 when driven. The interconnect bus 160 may be arranged along an edge margin and may provide routing for drive lines, reference / ground lines, and optional addressing lines to the plurality of PDLC regions 110. Electrical coupling between the interconnect bus 160 and the input conductive coating of each PDLC region 110 may be achieved by patterned busbars at the panel edge, alignment of bonding pads, and conductive joining materials, including anisotropic conductive film (ACF), conductive adhesives, or compliant spring contacts retained at the perimeter. By way of example, the interconnect bus 160 may be implemented as a flexible printed circuit with parallel conductive traces laminated along the edge of the PDLC panel overlay 100, and exposed traces may be bonded to corresponding edge electrodes of the input conductive coatings using an anisotropic conductive film to form low-resistance connections. The glazing 20 may encompass a transparent or translucent pane or assembly configured to admit light and provide an environmental barrier, including monolithic glass, laminated glass, insulated glazing units, tempered or chemically strengthened glass, or polymeric glazing substrates; the exposed surface may correspond to an interior or exterior surface of a planar or curved glazing 20 that remains accessible for attachment of the PDLC panel overlay 100.

[0221] The interconnect bus 160 may be connected 2020 to an edge control module 300. The purpose of an edge control module 300 may be to drive a single PDLC panel overlay 100 or a subset of conductors associated therewith, typically in proximity to the edge control module 300. Multiple edge control modules 300 may be connected and orchestrated by an external control module 350. By way of non-limiting example, the edge control module 300 may include a communication interface, a control-logic subsystem, a waveform-generation subsystem, a power-conversion subsystem, a sensing and telemetry subsystem, and a protection subsystem that may cooperate to receive commands, decode control data, synthesize drive signals, measure electrical responses, and report status. The communication interface may receive a data signal and a power feed from an upstream control path, may decode address and command fields, and may forward timing information to the control-logic subsystem, wherewith command integrity and synchronization may be maintained. The control-logic subsystem may map received commands to PDLC regions 110 associated with conductors of the interconnect bus 160, may schedule updates to avoid current spikes across multiple regions, and may forward unconsumed commands to a downstream edge control module 300 for orchestration across multiple edge control modules 300. The waveform-generation subsystem may synthesize alternating-current drive signals parameterized by amplitude and frequency according to desired transmission states, may manage phase relationships tolimit electromagnetic coupling, and may gate individual region lines through a selection network onto the interconnect bus 160. The power-conversion subsystem may condition an input supply into regulated logic rails and isolated actuation rails for PDLC drive, whereby galvanic isolation between logic domains and output stages may be preserved. The sensing and telemetry subsystem may measure output voltage and current delivered to conductors of the interconnect bus 160, may estimate load impedance to detect open or short conditions, and may encode status messages for upstream reporting. The protection subsystem may enforce over-current limits, over-temperature limits, short-circuit detection, and open-load detection, and may isolate affected channels while maintaining operation on unaffected channels.

[0222] A concrete interconnection arrangement may be provided where the interconnect bus 160 is terminated in a keyed low-profile board-to-cable connector on the edge control module 300, and a mating flexible printed cable laminated to an edge of a PDLC panel overlay 100 may engage the connector, whereby installation and service replacement may be facilitated. In the aforementioned arrangement, individual conductors of the interconnect bus 160 may be assigned to drive electrodes corresponding to respective PDLC regions 110 and to a reference electrode, and optional identification conductors of the interconnect bus 160 may convey panel metadata to the edge control module 300 for automatic configuration. During operation, the edge control module 300 may receive a frame of commands defining target transmission states for addressed PDLC regions 110, may decode the frame to resolve region identifiers, may generate synchronized alternating-current drive waveforms for the addressed PDLC regions 110, and may transmit the waveforms through the interconnect bus 160 to input conductive coatings of the addressed PDLC regions 110. Return telemetry obtained from voltage and current sensing of the interconnect bus 160 may be encoded into a status message and may be transmitted upstream to the external control module 350 for orchestration of multiple edge control modules 300. A daisy-chain topology may be used in which a first edge control module 300 forwards unconsumed commands to a second edge control module 300 via a downstream link, where device addressing may be established by preconfigured identifiers or by discovery at power-up.

[0223] Alternating current (AC) power and a data signal may be supplied 2030 to the edge control module 300 from an external control module 350. The data signal may be adjusted 2040 to drive the plurality of PDLC regions 110 via the edge control module 300. The data signal may be used to convey command frames that identify targeted PDLC regions 110, specify desired transmission states, and define waveform parameters including amplitude, frequency, phase relationship, and update duration, whereby the edge control module 300 may synthesize and apply corresponding alternating-current drive waveforms to conductors of the interconnect bus 160. The data signal may further provide timing references, sequencing directives, and transition profiles such as ramp rates and hold intervals, wherewith switching transients may be moderated and simultaneous region updates may be coordinated across multiple edgecontrol modules 300. The data signal may include configuration data such as region-to-conductor mapping, grouping definitions, and calibration coefficients for compensating panel-to-panel variation of the plurality of PDLC regions 110, thereby enabling consistent optical performance across a multi-region installation. The data signal may also carry supervisory commands including global enable, emergency override, and safe-state directives that may be acted upon by the edge control module 300 in response to building-automation events. The data signal may enable bidirectional communication in which telemetry such as output voltage, output current, inferred load impedance, temperature, and fault codes measured by the edge control module 300 may be reported upstream to the external control module 350 for monitoring and closed-loop adjustment of drive parameters. The data signal may incorporate addressing fields for device discovery and orchestration of multiple edge control modules 300 and may incorporate integrity checks such as sequence markers and error-detection codes to ensure reliable application of commanded states to the plurality of PDLC regions 110. The data signal may be conveyed over a dedicated communication link or may be superimposed on the AC power supplied 2030 by modulation, wherewith a single cable may deliver both power and control to the edge control module 300.

[0224] Reference is now made to the drawings in which the activity diagram of Figure 9 depicts an exemplary method 2000 for retrofitting a glazing 20 with a PDLC panel overlay 100, illustrating attachment via an optically clear adhesive and / or a secondary frame, and subsequent connection and driving via an edge control module 300, in accordance with the teachings of the present invention.

[0225] Attaching 2010 the PDLC panel overlay 100 may include applying 2012 an optically clear adhesive and / or installing 2014 a secondary frame retained within a window reveal of the glazing 20. The optically clear adhesive may be selected from pressure-sensitive optically clear acrylic adhesive films configured for dry lamination, liquid optically clear resins (e.g., ultraviolet-curable acrylates) configured for in-situ curing between the PDLC panel overlay 100 and the glazing 20, and optically clear silicone adhesives or gels configured to provide compliance for differential thermal expansion between the PDLC panel overlay 100 and the glazing 20. Adhesive selections may provide low haze, high visible transmittance, ultraviolet stability, and chemical compatibility with a polymer-dispersed liquid crystal medium.

[0226] Application of a pressure-sensitive optically clear acrylic adhesive film may include surface preparation of the glazing 20 and the PDLC panel overlay 100, alignment using temporary registration features, progressive roll-down to expel air, and perimeter sealing with a moisture-resistant transparent sealant, where spacers embedded in the film may establish a controlled bond-line thickness. Application of a liquid optically clear resin may include dispensing onto an attachment area, establishing a uniform gap with non-viewable spacers, flooding the interface to avoid entrapped bubbles, and curing through the glazing 20 or through the PDLC panel overlay 100 using actinic radiation or thermal energy, where thecured resin may provide index matching to reduce interfacial reflections. Use of an optically clear silicone adhesive or gel may include bead or film placement along a defined attachment field and partial confinement by a transparent perimeter dam, where viscoelastic properties may limit stress transfer to the PDLC panel overlay 100 and may accommodate building movement while maintaining optical clarity.

[0227] The secondary frame retained within the window reveal of the glazing 20 may be a multi-piece perimeter carrier that defines a capture channel for the PDLC panel overlay 100 and may be held in place by non-invasive retention features acting on faces of the window reveal, including compression gaskets that bear against reveal surfaces, spring or wedge clips that expand laterally within the reveal, and adhesive pads or tapes placed on non-viewable reveal lands. The secondary frame may include an inner clamping bead or cover that engages the capture channel to distribute clamping pressure along edges of the PDLC panel overlay 100, may include compliant gaskets to cushion contact with the PDLC panel overlay 100 and to form a light and dust seal, and may incorporate shims or set screws to adjust planarity relative to the glazing 20 so that optical uniformity may be maintained. The secondary frame may further provide a concealed raceway for routing an interconnect bus 160 and for locating an edge control module 300 in proximity to an edge of the PDLC panel overlay 100, and may include removable trim segments to enable service access and field replacement of the PDLC panel overlay 100 without disturbing the glazing 20.

[0228] The edge control module 300 may be mounted within a perimeter frame of the glazing 20. Installation within the perimeter frame may be achieved by locating a low-profile carrier bracket within a reveal channel of the perimeter frame and retaining the carrier bracket by compression gaskets that react against reveal faces, spring clips that engage undercut grooves of the perimeter frame, or adhesive pads placed on non-viewable lands of the perimeter frame, whereby drilling into the glazing 20 may be avoided. The edge control module 300 may be enclosed in a slim enclosure that mates with the carrier bracket through a snap-in interface or captive screws, where the carrier bracket may define a cavity sized to maintain a defined setback from an edge of the glazing 20 and to provide airflow clearances. Where the perimeter frame includes removable glazing beads, a replacement glazing bead with an integrated utility recess may be installed and may provide a receptacle for the edge control module 300 and a concealed raceway for cables, with the replacement glazing bead engaging existing bead retention features of the perimeter frame. Where the perimeter frame provides accessory slots, the edge control module 300 may be mounted on slide-in nuts or T-slot anchors and may be positioned using slotted holes and shims to accommodate dimensional tolerances and to maintain non-contact with the glazing 20.

[0229] High-bond acrylic foam tapes or structural adhesives may be used on continuous, non-structural flange surfaces of the perimeter frame to bond a mounting plate that receives the edge control module 300, with surface preparation and a defined bond-line thickness applied to achievelong-term adhesion while permitting differential thermal expansion between the perimeter frame and the mounting plate. Thermal management may be provided by a heat-spreading baseplate of the edge control module 300 that interfaces with metallic portions of the perimeter frame through thermally conductive, electrically insulating pads, whereby heat generated by electronics of the edge control module 300 may be conducted into the perimeter frame without compromising electrical isolation. Environmental sealing may be provided by gaskets between the enclosure of the edge control module 300 and the carrier bracket and by sealing features that avoid obstruction of drainage paths and weep holes of the perimeter frame, where moisture ingress to the enclosure of the edge control module 300 may be limited while condensation management of the perimeter frame may be preserved. Cable routing within the perimeter frame may be accommodated by a concealed raceway or conduit integrated into the carrier bracket, with strain-relief features and bend-radius guides that lead to a connector interface at an edge of a PDLC panel overlay 100, whereby installation and service replacement may be facilitated. Serviceability within the perimeter frame may be supported by a hinged or removable cover of the carrier bracket with captive fasteners, keyed connectors to prevent mis-mating, and space for a service loop, where removal and replacement of the edge control module 300 may be performed without disturbing the glazing 20 or the perimeter frame.

[0230] Reference is now made to the drawings in which the activity diagram of Figure 10 depicts an exemplary method 2000 for retrofitting a glazing 20 with a PDLC panel overlay 100, further showing daisy-chained edge control modules to drive a second PDLC panel overlay 100' in response to a distributed data signal, and in which the block diagram of Figure 27 depicts an exemplary Polymer- Dispersed Liquid Crystal (PDLC) retrofit system 6000 used with daisy-chaining in accordance with the teachings of the present invention.

[0231] The PDLC panel overlay 100 may be a first PDLC panel overlay and the edge control module 300 may be a first edge control module. The first edge control module 300 may be connected 2050 to a second edge control module 300'. The second edge control module 300' may be configured to drive a second PDLC panel overlay 100'. The data signal may be adjusted 2060 to drive the second PDLC panel overlay 100' via the first edge control module 300 and the second edge control module 300'. Optionally, in a daisy-chain arrangement, an external control module 350 may supply alternating current (AC) power and the data signal to the first edge control module 300; the first edge control module 300 may act on commands addressed to the first PDLC panel overlay 100, and unconsumed commands of the data signal may be forwarded downstream to the second edge control module 300' for application to the second PDLC panel overlay 100'. In such embodiments, each edge control module 300 may include an upstream port that receives power and the data signal and a downstream port that forwards power and the data signal, whereby a single trunk connection from the external control module 350 may serve multiple edge control modules 300 in sequence. Telemetry generated by each edge control module 300 may be inserted into areturn communication path and propagated upstream to the external control module 350. The daisy-chain arrangement may be generalized such that the second edge control module 300' may be connected to a third edge control module 300" configured to drive a third PDLC panel overlay 100", and so on for a plurality of edge control modules 300, each associated with a corresponding PDLC panel overlay 100, where the data signal may be adjusted 2060 to address any subset of PDLC regions 110 across the plurality and unaddressed commands may continue downstream until a designated edge control module 300 is reached. Addressing of edge control modules 300 in the daisy-chain arrangement may be established by preconfigured identifiers or by discovery at power-up, and command frames of the data signal may include device and region identifiers so that each edge control module 300 acts only on commands intended for PDLC regions 110 coupled through an interconnect bus 160 of the corresponding PDLC panel overlay 100.

[0232] The plurality of PDLC regions 110 of the PDLC panel overlay 100 are driven according to the method 1000 for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel 100 of the first aspect, described hereinabove.

[0233] A third aspect of the techniques described herein relates to a method 3000 for displaying a transparency map using a multi-region selective-opacity panel 100. Reference is now made to the drawings in which the activity diagram of Figure 11 depicts an exemplary method 3000 that includes mapping 3010 regions of a transparency map to panel regions 110 and configuring 3020 the transparency of mapped panel regions accordingly. Reference is also made to the drawings in which the block diagram of Figure 28 depicts an exemplary system 7000 for displaying a transparency map using a multi-region selective-opacity panel 100. The multi-region selective-opacity panel 100 may comprise a Polymer- Dispersed Liquid Crystal (PDLC) panel 100, such as described hereinabove, or another electrically responsive technology configured to vary optical transmissivity under an applied drive signal, including suspended particle devices and electrochromic devices, adapted as appropriate to their response characteristics.

[0234] A transparency map region of a transparency map may be mapped 3010 to at least one panel region from a plurality of panel regions 110 of the multi-region selective-opacity panel 100, and a transparency of the at least one panel region 110 may be configured 3020 in accordance with a transparency value of the transparency map region. Mapping 3010 may be performed according to a correspondence function that associates positions in the transparency map with positions on the panel, and may include one-to-one, one-to-many, or many-to-one associations to accommodate differences in resolution between the transparency map and the plurality of panel regions 110. The correspondence function may include resampling and / or aggregation, for example selecting a representative value for a panel region 110 from multiple contributing transparency map samples and / or distributing a transparencyvalue across multiple panel regions 110. Configuring 3020 may include setting each addressed panel region 110 to an at least partially transmissive or at least partially scattering state consistent with the transparency value, and may include intermediate levels obtained by modulation of an effective drive, as described herein.

[0235] The transparency map may be an image and the transparency map region may be an image region. The transparency value may be derived from at least one of a transparency channel, an opacity channel, a luminance channel, and / or a grayscale channel of the image. Where an opacity channel is present, the transparency value may be obtained by an inversion (e.g., transparency = 1 - opacity, after normalization to a common scale), optionally with gamma or tone-mapping applied to suit perceptual or material response characteristics. Where a luminance and / or grayscale channel is used, the transparency value may be obtained by normalization of channel intensity, optionally followed by thresholding and / or quantization to the achievable set of panel transparency states. In further embodiments, multiple channels may be combined, for example by a weighted sum or by selecting the most restrictive channel for privacy-oriented content, while preserving a monotonic relationship between channel intensity and the configured transparency.

[0236] The plurality of panel regions 110 may be configured as a regular grid, the image may be a raster image, the image region may be a pixel of the raster image, and mapping 3010 the image region may include mapping the pixel to the regular grid. The mapping may preserve aspect ratio of the image (e.g., letterbox / pillarbox) or may scale and crop to fill the available panel extent. Resampling may be performed using one or more non-limiting techniques including nearest-neighbor, bilinear, and bicubic interpolation, selected according to desired sharpness versus smoothness at panel-region boundaries. By way of example, a raster image of 1920 x 1080 pixels may be scaled to a panel grid of 96 x 54 panel regions 110 using bilinear interpolation, with each panel region 110 assigned a transparency value derived from the corresponding resampled pixel. In further embodiments, grid pitch may be selected according to the application, for example a panel-region pitch between about 2 mm and about 100 mm, optionally between about 5 mm and about 50 mm, balancing optical resolution, manufacturing feasibility, and interconnect density.

[0237] In operation, lower transparency values may be used to configure a panel region 110 toward an at least partially scattering state, and higher transparency values may be used to configure a panel region 110 toward an at least partially transmissive state, thereby reproducing darker and lighter portions of the transparency map, respectively. Perceived brightness may depend on ambient illumination and viewing geometry; accordingly, in some embodiments a calibration curve may be applied so that the configured transparency better matches the intended appearance under expected lighting conditions. As a non-limiting illustration, a grid of 100 x 100 panel regions 110 may be driven to reproduce a 100 x 100pixel grayscale image, or a higher-resolution image resampled thereto, where each panel region 110 is configured to a transparency proportional to the corresponding pixel intensity.

[0238] Reference is now made to the drawings in which the activity diagram of Figure 12 depicts an exemplary method 3000 for displaying an image using a multi-region selective-opacity panel 100, illustrating processing 3030 of the image into one or more intensity channels and a transparency channel, configuring 3040 regional transparency per the transparency channel, and projecting 3050 light per the intensity channels, in accordance with the teachings of the present invention.

[0239] The image may be processed 3030 to obtain one or more intensity channels and a transparency channel. The transparency channel may be obtained directly (e.g., from an alpha channel) or derived from one or more image channels (e.g., from luminance or grayscale by thresholding, tone-mapping, and / or normalization). The one or more intensity channels may include a color channel, a luminance channel, and / or a chrominance channel. Non-limiting examples of channel formats include RGB, RGBA, CMYK, and YCbCr / YPbPr; conversions among such spaces may be applied so that the transparency channel and intensity channels are expressed on a common scale suitable for driving the panel 100 and a cooperating light source.

[0240] The transparency of at least one panel region 110 may be configured 3040 in accordance with the transparency channel. Configuring 3040 may include adjusting each mapped panel region 110 toward a higher or lower transparency consistent with the transparency value assigned to that region, optionally with gamma correction and / or quantization suitable for the achievable set of panel transparency states. In PDLC embodiments, configuring 3040 may be realized by modulating an effective AC drive to set the region 110 toward an at least partially transmissive or an at least partially scattering condition.

[0241] Light may be projected 3050 onto the multi-region selective-opacity panel 100 in accordance with the one or more intensity channels. The projected light may be produced by any suitable light source 180, including a video projector, a laser projector, an addressable LED array, or a luminaire array, with spectral content and intensity modulated per the intensity channels. A color channel (e.g., RGB) may drive the projector's primaries while the transparency channel independently controls regional transmissivity, thereby producing bright, color-accurate content on regions configured to scatter / reflect while leaving other regions substantially transparent. In further embodiments, ambient light (e.g., sunlight or skylight) may serve as the illuminating source, with the panel 100 modulated to create high-contrast shapes and silhouettes where regions are rendered more scattering.

[0242] By way of example, projected signage may be rendered on a storefront window as illustrated in Figure 32 by configuring background panel regions 110 to higher transparency while configuring logo or text regions to lower transparency, and projecting colored content per the one or more intensity channelsto achieve high contrast and legibility. As another example, a light source may be used to create shadows or silhouettes as illustrated in Figure 31 by projecting light in accordance with intensity channels while configuring selected panel regions 110 to lower transparency to diffuse and back-scatter light toward an observer. In a building-scale installation as illustrated in Figure 29, a raster image may be mapped to a grid of panel regions 110, the transparency channel may set each region's transmissivity, and a projector may illuminate the fagade per color / luminance channels to display large-format imagery. In a further embodiment as illustrated in Figure 30, a dedicated light source 180 may be positioned to project through the panel 100, where regional transparency is modulated by the transparency channel and the source is driven per the intensity channels to form colored features and controlled shadows.

[0243] The one or more intensity channels may include at least one of a color channel, a luminance channel, and a chrominance channel. Optionally, the transparency channel itself may be reused as an intensity channel (e.g., for monochrome content), or a weighted combination of channels may be employed to suit ambient conditions while maintaining a monotonic relationship between the transparency value and configured transmissivity.

[0244] Reference is now made to the drawings in which the activity diagram of Figure 13 depicts an exemplary method 3000 for displaying video on a multi-region selective-opacity panel 100, illustrating per-frame mapping and transparency configuration with intensity / transparency channel processing and light projection repeated for successive frames, in accordance with the teachings of the present invention.

[0245] The image may be a frame from a video stream and the configuring 3020 of the transparency may be repeated for successive frames thereof. Optionally, a frame rate of the video stream may be at least 20 frames per second. In further embodiments, frame rates of about 24, 30, or 60 frames per second may be used, and rates up to about 120 frames per second may be employed where the panel response permits. Per-frame operation may include acquiring a frame, mapping 3010 the frame's image regions to panel regions 110, deriving or updating a transparency channel (e.g., from alpha, luminance, or a computed matte), resampling to the panel-region grid, and configuring 3040 the transparency of the mapped panel regions 110 accordingly. Where one or more intensity channels are present, light may be projected 3050 per frame in accordance with the intensity channels, with timing synchronized to transparency updates.

[0246] To improve visual quality, optional temporal filtering and / or double-buffering may be used so that the configured transparency changes appear smooth across successive frames while maintaining a substantially zero-mean AC drive at the panel. Gamma and tone-mapping may be applied per frame so that the transparency values remain perceptually monotonic under expected ambient lighting. Geometric registration between video coordinates and panel-region layout may be calibrated once and reused acrossframes, with per-frame resampling performed by non-limiting methods such as nearest-neighbor, bilinear, or bicubic interpolation.

[0247] By way of example, animated content such as logos, tickers, wayfinding arrows, silhouettes, or occupancy masks may be rendered by repeating the configuring 3020 per incoming video frame at or above 20 frames per second. In further examples, cropped regions of interest (e.g., hands or faces) or high-contrast notifications may be presented against a see-through background by assigning higher transparency values to background regions and lower transparency values to regions intended to scatter projected light, with optional color projection per intensity channels.

[0248] The plurality of panel regions 110 need not be arranged as a regular grid. Irregular tilings, non-rectilinear lattices, curved panels, and panels with omitted or inactive regions may be used. Mapping 3010 may be defined by a calibration transform between transparency-map coordinates and panel-region coordinates, which may be affine, projective, polynomial, spline-based, or piecewise-defined to accommodate optical and mechanical distortions.

[0249] Resampling and aggregation used during mapping 3010 may include nearest-neighbor, bilinear, and bicubic interpolation, as well as aggregation operators when multiple image samples contribute to a single panel region 110, including mean, weighted mean, median, maximum, and minimum. Morphological operations (e.g., dilation / erosion) may be optionally applied to bias a rendered shape toward increased or decreased apparent openness or occlusion according to application requirements.

[0250] Spatial and / or temporal dithering may be employed to increase apparent grayscale depth or shape fidelity at a given panel-region pitch. Non-limiting examples include ordered dithering and error-diffusion dithering across neighboring panel regions 110, and temporal modulation of transparency values across successive updates, while maintaining a substantially zero-mean AC drive. Time-averaged effective transparency may thus approximate a target value even where the panel supports a limited set of instantaneous drive levels.

[0251] Vector graphics (e.g., text, icons, line art) may be rasterized to the panel-region layout with antialiasing prior to mapping 3010. Stroke weights, kerning, and hinting may be adjusted to preserve legibility at the available panel-region pitch.

[0252] Per-region calibration may be applied so that configured transparency values compensate for panel-to-panel and region-to-region variation. Calibration may include per-region lookup tables or parametric corrections derived from factory or in-situ measurements, and may optionally include temperature compensation. Gamma and tone-mapping may be applied so that perceptual transparency remains monotonic under expected ambient lighting.

[0253] Partial updates may be used to reduce latency and bandwidth by updating only regions whose target transparency has changed beyond a threshold. Double-buffering or page-flipping of control data may be used so that transparency changes occur coherently across the panel. Where a cooperating light source 180 is used, projection timing may be synchronized to transparency updates to reduce tearing or mismatch artifacts.

[0254] Reference is now made to the drawings in which the activity diagram of Figure 14 depicts an exemplary method 3000 including obtaining 3110 a position of interest 190 relative to the multi-region selective-opacity panel 100, rendering 3115 a view pattern in a transparency map located relative to the position of interest 190, mapping 3010 the view pattern to at least one panel region 110, and configuring 3020 the transparency of the at least one panel region 110 corresponding to the view pattern to create a view across the multi-region selective-opacity panel 100. Optionally, the transparency map may be updated 3120 when the position of interest 190 moves. The multi-region selective-opacity panel 100 may comprise a Polymer-Dispersed Liquid Crystal (PDLC) panel as described herein or another electrically responsive technology adapted to vary optical transmissivity under an applied drive.

[0255] A position of interest 190 may be obtained 3110 relative to the multi-region selective-opacity panel 100. The position of interest 190 may correspond to a location of an observer, a user-selected point, a seat location, or a tracked object or feature proximate to the panel. The position of interest 190 may be expressed in panel-relative coordinates, for example lateral and vertical offsets on the panel and optionally a distance from the panel plane and / or an elevation. The position of interest 190 may be determined by one or more sensing or localization modalities, including vision-based detection, range or presence sensing, room or vehicle telemetry, or manual selection via a user interface, and may be updated at a rate suitable for responsiveness while maintaining stability. Optional temporal filtering or outlier rejection may be applied to reduce jitter.

[0256] A view pattern may be rendered 3115 in the transparency map located relative to the position of interest 190, the view pattern defining a view region having transparency values greater than those of surrounding regions. Rendering 3115 may include generating a parametric or pixel representation of the view region in transparency-map coordinates and assigning higher transparency values within the region and lower transparency values outside the region, optionally with softened edges to reduce visible discontinuities. The view pattern may have a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person shaped pattern. By way of non-limiting example, a circular pattern may be used to create a localized "peephole” region aligned to a nearby observer; a vertical pattern may provide a tall, narrow band suited to a standing observer; a horizontal pattern may provide a wide band suited to a seated observer or panoramic scene; and a person shaped pattern may approximate a silhouette sized and positioned according to an estimated posture and elevation.

[0257] Mapping 3010 of the rendered view pattern to the plurality of panel regions 110 may be performed according to a correspondence function between transparency-map coordinates and panel-region coordinates as described herein, and may include resampling techniques such as nearest-neighbor, bilinear, or bicubic interpolation. Where multiple transparency-map samples contribute to a single panel region 110, aggregation (for example, mean or weighted mean) may be used; where a single sample spans multiple panel regions 110, the transparency value may be distributed accordingly. Configuring 3020 the transparency of the at least one panel region 110 corresponding to the view pattern may include setting panel regions 110 mapped inside the view region to higher transparency than surrounding panel regions 110, thereby creating a view across the multi-region selective-opacity panel 100. Optional gamma or tone-mapping may be applied so that transitions appear perceptually smooth at panel-region boundaries.

[0258] The transparency map may be updated 3120 when the position of interest 190 moves so that the view region remains located relative to the changed position of interest 190. Updates may include translation, resizing, or reshaping of the view pattern in the transparency map while maintaining higher transparency values within the view region than in surrounding regions. Optional smoothing, hysteresis, or motion prediction may be applied to successive updates to limit flicker and improve visual comfort, with update cadence selected in view of panel response times. Where multiple positions of interest are present, selection rules may be applied, including a primary position of interest 190, a union of multiple view regions, or time-multiplexed presentation, provided that each view region rendered maintains transparency values greater than those of its local surrounding regions.

[0259] By way of illustration, a private office window may render a horizontal view pattern aligned to a seated desk position so that outward visibility is provided across a band while surrounding regions remain at lower transparency for privacy. In another illustration, a museum case may render a circular view pattern that follows a visitor's location along the glazing to create a moving local region of higher transparency while surrounding regions remain more scattering to reduce reflections. These examples are non-limiting and are provided to demonstrate that rendering 3115 a view pattern located relative to the position of interest 190 and configuring 3020 the transparency of corresponding panel regions 110 may create a view across the multi-region selective-opacity panel 100. Subsequent embodiments further incorporate sight direction, two-sided line-of-sight alignment, distance and elevation factors, and dual-threshold adjustments.

[0260] The position of interest 190 may include a distance relative to the multi-region selective- opacity panel 100. Configuring 3020 may include adjusting at least one panel region 110 of the multiregion selective-opacity panel 100 from an at least partially scattering configuration to an at least partially transmissive configuration when the distance of the position of interest 190 is within a distance threshold.A panel-relative reference frame may be established, for example with a plane corresponding to the panel and a normal vector defining an outward direction. A reference point associated with the position of interest 190 (e.g., an eye midpoint of an observer, a centroid of a tracked object, or another application-defined point) may be localized relative to the panel, and a distance thereto may be computed and compared to the distance threshold. When the computed distance satisfies the distance threshold, one or more panel regions 110 located at or near an intersection of a selected direction with the panel plane may be transitioned toward the at least partially transmissive configuration while surrounding panel regions 110 remain at least partially scattering.

[0261] The distance may be defined in any of several ways consistent with the intended behavior, including: a perpendicular distance from the reference point to the panel plane; a range along a selected direction (e.g., a line of sight) from the reference point to an intersection with the panel plane; or a shortest Euclidean distance from the reference point to a footprint of a selected panel region 110 embedded in three-dimensional space. A consistent definition may be used for comparison to the distance threshold. Non-limiting sensing and localization modalities suitable to obtain the position of interest 190 and distance include time-of-flight or structured-light depth cameras, stereo vision, ultrasonic triangulation, radio-frequency ranging (e.g., ultra-wideband tags localized relative to anchors on a panel frame), millimeter-wave radar, or vision-based detection with extrinsic calibration to the panel coordinate frame. Where applicable, photometric sensing may be used to localize a bright feature and derive distance by triangulation. Estimates may be filtered temporally to reduce jitter and outliers prior to threshold evaluation.

[0262] By way of illustration, when an observer approaches the multi-region selective-opacity panel 100 and the perpendicular distance drops below a configured distance threshold (for example, about 0.3- 3.0 m, optionally about 0.5-1 .5 m depending on installation), a set of neighboring panel regions 110 centered at the intersection point may be transitioned toward an at least partially transmissive configuration to create a localized view region, and the same regions may be returned toward an at least partially scattering configuration when the observer moves beyond the threshold. Neighborhood selection may consider the panel-region pitch and desired field of view.

[0263] Optionally, a size of the view region may be a monotonically decreasing function of the distance of the position of interest 190. A characteristic size parameter of the view region (e.g., a radius for a circular pattern, a width for a vertical pattern, or a height for a horizontal pattern) may be defined as S(d) = f(d), where f(d) is monotonically non-increasing with distance d. Non-limiting examples include a piecewise-linear function that decreases from a maximum size near the panel to a minimum size beyond a predefined range, or an inverse or logarithmic function that tapers gradually with distance. Practical ranges may be selected according to application; by way of example, a circular view radius may varybetween about 50-300 mm, optionally about 75-200 mm, decreasing with increasing distance so that nearer observers are provided a larger aperture while distant observers are provided a smaller aperture.

[0264] Optionally, transparency values within the view region may be a monotonically decreasing function of the distance of the position of interest 190. A transparency assignment T(d) may be defined for panel regions 110 inside the view region such that T(d) is monotonically non-increasing with distance d. Non-limiting examples include mapping distance to a target transparency via a calibrated curve (e.g., a linear or gamma-adjusted mapping) so that nearer positions yield higher transparency and farther positions yield equal or lower transparency, while surrounding regions outside the view region maintain lower transparency to preserve privacy or shading. Where intermediate transparency levels are available, quantization may be applied to T(d) consistent with the achievable set of drive states while maintaining the monotonic relationship across distance.

[0265] The position of interest 190 may further include an elevation, and rendering 3115 a view pattern may include locating the view pattern relative to the elevation in the transparency map. The elevation may be expressed as a vertical coordinate of a reference point associated with the position of interest 190 (for example, an eye midpoint for an observer or an application-defined point) in a panel-relative coordinate frame. The elevation may be obtained by transforming a three-dimensional estimate from a sensor into the panel frame and extracting a component along a defined vertical axis; by computing a height above a baseline (e.g., a bottom edge of the multi-region selective-opacity panel 100) using calibrated geometry; or by estimating a floor plane with a depth sensor and taking the orthogonal distance from the reference point to that plane. Locating the view pattern relative to the elevation may include selecting rows or vertically distributed panel regions 110 corresponding to an elevation band around the measured height and assigning higher transparency values within that band than in surrounding regions. By way of non-limiting illustration, when the elevation corresponds to a standing observer's eye height above the panel centerline, a view pattern (e.g., a horizontal pattern or a person shaped pattern) may be positioned higher on the transparency map so that mapped panel regions 110 near the upper portion of the panel are configured 3020 to higher transparency. When the elevation corresponds to a seated observer, the view pattern may be positioned lower so that lower panel regions 110 are configured 3020 to higher transparency. For a light source near a ceiling, panel regions 110 nearer to an upper elevation band may be configured 3020 to higher transparency to pass illumination along the measured elevation. In further embodiments, a thickness of the elevation band used for the view pattern may be selected according to the application, for example a characteristic band or aperture height between about 50 mm and about 300 mm, optionally about 100 mm to about 200 mm, while maintaining higher transparency values within the band than in surrounding regions.

[0266] The position of interest 190 may be a position of an observer and the view may allow the observer to see through the multi-region selective-opacity panel 100. In such embodiments, rendering 3115 the view pattern located relative to the observer's position and configuring 3020 the transparency of at least one panel region 110 corresponding to the view pattern may create a region of higher transparency aligned to the observer's vantage so that external scenery is visible through the panel 100, while surrounding regions remain at lower transparency for privacy or shading. When the observer moves, the transparency map may be updated 3120 so that the view pattern translates and / or resizes to remain located relative to the observer, maintaining see-through capability with optional smoothing to limit flicker. Non-limiting examples include a localized clear area appearing at the observer's eye height when approaching a window, or a horizontally elongated clear band aligned to a seated observer, in each case with surrounding panel regions 110 maintained at lower transparency.

[0267] Reference is now made to the drawings in which the activity diagram of Figure 15 depicts an exemplary method 3000 for providing a view using a multi-region selective-opacity panel 100 located relative to an intersection of an observer's sight direction with the panel, in accordance with the teachings of the present invention.

[0268] A sight direction of the observer may be obtained 3130, and the view pattern may be located 3135 relative to an intersection of the sight direction with the multi-region selective-opacity panel 100. The sight direction may be represented as a gaze vector originating from a reference point associated with the observer (for example, an eye midpoint) and expressed in a panel-relative coordinate frame. The sight direction may be obtained using one or more sensing modalities, including non-limiting examples such as: camera-based eye-gaze estimation (monocular or binocular) mounted near the panel; head-pose estimation combined with a fixation model to infer gaze; wearable eye trackers providing gaze vectors; or inertial / vision fusion where head orientation from an inertial measurement unit is calibrated to the panel frame. A calibration procedure may establish a rigid transform between the sensing system and the panel frame so that the gaze vector is expressed consistently with panel coordinates. Update rates may be selected in view of responsiveness and stability, for example about 30-120 Hz, with temporal filtering or hysteresis optionally applied to reduce jitter.

[0269] The intersection of the sight direction with the multi-region selective-opacity panel 100 may be computed by casting a ray from the reference point along the sight direction and determining its intersection with a plane corresponding to the panel. If the sight direction is substantially parallel to the panel plane (e.g., within a small angular threshold), a fallback may be used, such as clamping the intersection to a nearest boundary or selecting a default region proximate to the projected reference point. The intersection may be clipped to the panel extents and converted to transparency-map coordinates so that mapping 3010 to panel regions 110 may be performed. Where refractive elements or curved glazingsare present, an application-specific geometric model may optionally be used to compensate for systematic offsets so that the located view pattern remains aligned with the perceived line of sight 195.

[0270] Locating 3135 the view pattern relative to the intersection may include centering a view pattern (for example, a circular, vertical, horizontal, or person shaped pattern as described herein) at or around the intersection point in the transparency map and assigning higher transparency values within the view region than in surrounding regions. Configuring 3020 the transparency of at least one panel region 110 corresponding to the view pattern may thereby create a localized region of higher transparency aligned to the observer's line of sight 195 through the multi-region selective-opacity panel 100. The view pattern may be resized according to application constraints, for example selecting a minimum aperture sufficient to accommodate gaze-estimation uncertainty (e.g., on the order of tens of millimeters at typical viewing distances), and may employ softened edges to reduce visible discontinuities at panel-region boundaries. The transparency map may be updated 3120 as the sight direction changes so that the view region tracks the intersection smoothly over time, with optional dead-bands or rate limits to reduce flicker during small, rapid eye movements.

[0271] By way of illustration, when an observer standing near a window scans across a scene, the obtained sight direction 3130 may define a moving intersection on the panel, and a circular view pattern centered at that intersection may be rendered 3115 and located 3135 so that mapped panel regions 110 are configured 3020 to higher transparency along the instantaneous line of sight 195 while surrounding regions remain at lower transparency. In another illustration, for a seated observer looking downward toward street level, a horizontal view pattern may be located relative to the intersection below the panel centerline so that visibility is provided through a lower band aligned to the gaze while maintaining privacy elsewhere.

[0272] The position of interest 190 may be a position of a light source and the view may allow the light source to illuminate through the multi-region selective-opacity panel 100. In such embodiments, obtaining 3110 the position of interest 190 may include determining a location of the light source relative to the panel. The location may be known a priori (e.g., a fixed luminaire mounted at a registered position), may be measured by sensing (e.g., photometric localization of a bright source in one or more cameras and triangulation using a calibrated baseline; detection by time-of-flight or structured-light sensors; ranging by ultra-wideband tags affixed to a movable light head), or may be provided by device telemetry (e.g., pan / tilt / zoom encoders or goniometer readouts reporting pose of a spotlight). Where available, an orientation or beam axis of the light source may be estimated from sensor data or device telemetry and expressed in a panel-relative coordinate frame using a calibrated transform.

[0273] Rendering 3115 a view pattern may include locating the view pattern relative to a path of illumination from the light source to the panel. A direction (e.g., a beam axis) may be used to cast a rayfrom the light-source position toward the panel plane and to compute an intersection point. The intersection point may be converted to transparency-map coordinates and used to center a view pattern whose shape is selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person shaped pattern, with higher transparency values assigned within the view region than in surrounding regions. A characteristic size of the view region may be selected according to a beam footprint at the panel (e.g., a diameter consistent with beam divergence and standoff distance), optionally with softened edges to reduce visible discontinuities at panel-region boundaries. Mapping 3010 may associate the view pattern to at least one panel region 110, and configuring 3020 may set the transparency of the at least one panel region 110 in accordance with the transparency values of the view region so that illumination may pass through the panel along the intended path while surrounding regions remain at least partially scattering.

[0274] In further embodiments, the transparency map may be updated 3120 when the light source moves or when its aim changes so that the view region remains located relative to the current path of illumination. Update cadence may be selected consistent with panel response times, and optional smoothing or hysteresis may be applied to limit flicker during small aim adjustments. Where incidence angle varies significantly across the panel, transparency values inside the view region may optionally be modulated to compensate for angular losses so that sufficient flux passes through along the intended path, while preserving the relationship that transparency values within the view region remain greater than those of surrounding regions.

[0275] By way of illustration, when a spotlight is directed toward the multi-region selective-opacity panel 100, a circular view pattern centered at the beam intersection with the panel may be rendered 3115 and configured 3020 to higher transparency so that the beam passes through, and when the spotlight is redirected the view pattern may be translated to follow the new intersection; when the spotlight is extinguished, the view pattern may be removed and the affected panel regions 110 returned toward a lower transparency. As another illustration, a fixed architectural light located above the panel may be represented as the position of interest 190; a vertical or horizontal view pattern may be located relative to the measured elevation and intersection so that illumination passes through a selected band while adjacent regions remain at lower transparency for glare control.

[0276] The light source may comprise natural daylight, including sunlight and skylight. The position of interest 190 may thereby be obtained 3110 as a solar position defined by a direction vector (e.g., a solar elevation and azimuth) and, optionally, an effective point of incidence on the multi-region selective-opacity panel 100. For sunlight, the light source may be modeled as a distant source producing substantially parallel rays; the solar direction may be computed from ephemeris data using geographic coordinates, date, and time together with a building orientation reference, or may be estimated by sensing, for example using a sky-facing camera, a photodiode array, or a sun sensor whose readings are transformed into apanel-relative coordinate frame. Rendering 3115 a view pattern may include locating the view pattern relative to an intersection of the solar direction with the panel plane so that mapped panel regions 110 along the intended path are configured 3020 to higher transparency, thereby allowing daylight to illuminate through the panel 100, while surrounding regions remain at lower transparency. The transparency map may be updated 3120 over time as solar elevation and azimuth change diurnally and seasonally, with optional smoothing to limit flicker under intermittent cloud cover. By way of illustration, a horizontal view pattern may be positioned and sized according to the current solar direction to admit a daylighting band into an interior space, with a characteristic width selected to accommodate beam spread and incidence angle. In further embodiments where daylight is predominantly diffuse (e.g., overcast sky), a broader view pattern may be located relative to a dominant luminous region of the sky field inferred from the sensing modality, while maintaining that transparency values within the view region are greater than those of surrounding regions.

[0277] Reference is now made to the drawings in which the activity diagram of Figure 16 depicts an exemplary method 3000 for providing a view aligned to a computed line of sight 195 between positions on opposite sides of a multi-region selective-opacity panel 100, in accordance with the teachings of the present invention.

[0278] The position of interest 190 may be a first position of interest 190 located on a first side of the multi-region selective-opacity panel 100, and a second position of interest 192 may be obtained 3140 on a second side of the multi-region selective-opacity panel 100. The first and second positions of interest may be expressed in a panel-relative coordinate frame using sensing, localization, or telemetry as described herein. A line of sight 195 from the first position of interest 190 to the second position of interest 192 may be computed 3145, the line of sight 195 comprising an intersection at the multi-region selective- opacity panel 100. In one embodiment, the line of sight 195 may be represented parametrically between the two positions, and the intersection may be computed with a plane corresponding to the panel; the intersection may be clipped to the panel extents and converted to transparency-map coordinates. Where the line of sight 195 is substantially parallel to the panel plane or falls outside panel extents, a fallback may be applied, such as clamping to a nearest boundary or using a nearest-approach point consistent with application constraints.

[0279] The view pattern may be located relative to the intersection of the line of sight 195 at the multi-region selective-opacity panel 100. Locating may include centering a view pattern at or around the intersection in the transparency map, the view pattern defining a view region having transparency values greater than those of surrounding regions. Mapping 3010 may associate the view pattern to at least one panel region 110, and configuring 3020 may set the transparency of the at least one panel region 110 in accordance with the transparency values of the view region so as to create a view across the multi-regionselective-opacity panel 100 aligned to the computed line of sight 195. The view pattern may employ any of the shapes described herein (e.g., circular, vertical, horizontal, or person shaped), with characteristic size selected according to application, and edges optionally softened to reduce visible discontinuities at panel-region boundaries.

[0280] By way of illustration, a first position of interest 190 located on an interior side and a second position of interest 192 located on an exterior side may define a line of sight 195 whose intersection with the panel identifies where the view pattern is to be rendered and mapped; panel regions 110 corresponding to that view pattern may be configured to higher transparency while surrounding regions remain at lower transparency. In further embodiments, geometric registration between sensing systems and the panel frame may be established during installation so that the computed intersection remains aligned to perceived sight lines across varying vantage points.

[0281] The view may be updated 3150 when the second position of interest 192 moves. Updating 3150 may include re-acquiring the second position of interest 192 on a second side of the multi-region selective-opacity panel 100, re-computing 3145 a line of sight 195 from a first position of interest 190 on a first side to the second position of interest 192, determining an updated intersection of the line of sight 195 with the multi-region selective-opacity panel 100, and locating the view pattern relative to the updated intersection. Mapping 3010 may associate the relocated view pattern to at least one panel region 110, and configuring 3020 may set the transparency of the at least one panel region 110 in accordance with transparency values of the view region so that the view remains aligned to the changed line of sight 195. Where the updated intersection is near a panel boundary, clipping to panel extents may be applied; where the recomputed line of sight 195 is substantially parallel to the panel plane or misses the panel, a nearest-approach or fallback intersection consistent with the application may be used.

[0282] The update 3150 may translate, resize, and / or re-shape the view pattern according to changes in geometry. For example, where distance varies as the second position of interest 192 moves, a characteristic size of the view region may be adjusted using a monotonic distance function while maintaining higher transparency values within the view region than in surrounding regions. Optional temporal filtering, rate limiting, hysteresis, or motion prediction may be applied to successive updates to reduce visible flicker and accommodate panel response times while maintaining alignment to the moving second position of interest 192.

[0283] By way of illustration, when an observer at the first position of interest 190 looks toward an observee at the second position of interest 192 who is walking within a room on the opposite side, the second position of interest 192 may be re-acquired as the observee moves, the line of sight 195 and intersection may be recomputed, and the view pattern may be translated across the panel 100 so that mapped panel regions 110 near the updated intersection are configured 3020 to higher transparency whilesurrounding regions remain at lower transparency. As another illustration, when a first position of interest 190 is a light source and a second position of interest 192 is a moving target on the opposite side, the intersection may track the changing aim, and the transmissive footprint may be relocated by updating 3150 the view pattern so that illumination continues to pass through the panel 100 toward the moving target.

[0284] Reference is now made to the drawings in which the activity diagram of Figure 17 depicts an exemplary method 3000 for providing a view when first and second distances of positions of interest are within respective thresholds, in accordance with the teachings of the present invention.

[0285] The position of interest 190 may be a first position of interest 190 located on a first side of the multi-region selective-opacity panel 100, and a second position of interest 192 may be obtained 3140 on a second side of the multi-region selective-opacity panel 100. The first position of interest 190 may include a first distance relative to the multi-region selective-opacity panel 100 and the second position of interest 192 may include a second distance relative to the multi-region selective-opacity panel 100. Configuring 3020 may include adjusting 3155 at least one panel region 110 of the multi-region selective- opacity panel 100 from an at least partially scattering configuration to an at least partially transmissive configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold. The at least one panel region 110 adjusted at 3155 may correspond to a view pattern rendered 3115 and located relative to an intersection of a computed line of sight 195 3145 with the multi-region selective-opacity panel 100, as described herein.

[0286] The first distance and the second distance may be defined in a manner consistent with the intended behavior, including non-limiting examples such as: a perpendicular distance from each position of interest 190 to a plane corresponding to the multi-region selective-opacity panel 100; a range along the computed line of sight 195 from each position of interest 190 to the panel plane; or a shortest Euclidean distance from each position of interest 190 to a selected panel-region footprint embedded in three-dimensional space. A consistent definition may be used for comparing each distance to its respective threshold. Distances may be obtained by sensing or localization modalities as described herein (e.g., depth cameras, stereo vision, ultra-wideband ranging, radar), transformed into a panel-relative coordinate frame, and filtered temporally to reduce jitter prior to threshold evaluation.

[0287] The first distance threshold and the second distance threshold may be configurable according to application requirements. By way of non-limiting example, thresholds may be selected within a range of about 0.3 m to about 5 m, optionally about 0.5 m to about 2.0 m. Optional hysteresis bands may be applied around each threshold to reduce oscillation when a distance hovers near its threshold. When both distances satisfy their respective thresholds, panel regions 110 corresponding to the view pattern at or around the intersection may be transitioned toward higher transparency; when either distance does not satisfy its threshold, the affected panel regions 110 may be maintained at, or returned toward, a lowertransparency. Intermediate behaviors may also be used, including shrinking the view pattern or reducing transparency as either distance approaches its threshold from within.

[0288] By way of illustration, a first position of interest 190 may be an observer located approximately 1.0 m from the panel 100 on a first side, and a second position of interest 192 may be an observee approximately 1 .5 m from the panel on a second side. With a first distance threshold of 1 .5 m and a second distance threshold of 2.0 m, both distances satisfy their respective thresholds; panel regions 110 centered at the intersection of the line of sight 195 with the panel may be adjusted 3155 from an at least partially scattering configuration to an at least partially transmissive configuration to provide the view. As another illustration, a first position of interest 190 may be a light source located approximately 0.6 m from the panel on a first side and a second position of interest 192 may be a target located approximately 1 .0 m from the panel on a second side. With thresholds of 1.0 m and 1.5 m respectively, the distances satisfy the thresholds and the transmissive footprint centered at the intersection may be formed so that illumination passes through the panel along the intended path. In each case, if either distance subsequently exceeds its threshold, the transparency of the corresponding panel regions 110 may be reduced or the view pattern may be removed, consistent with privacy or shading objectives.

[0289] As depicted in Figure 30, the position of interest 190 may be a position of a light source located on a first side of the multi-region selective-opacity panel 100, and a view region may be configured to allow light from the light source to pass through the panel and project an image onto a surface located on a second side of the panel. Obtaining 3110 the position of interest 190 may include determining a location of the light source (and optionally an aim or beam axis) relative to the panel. Rendering 3115 a view pattern may include locating the view pattern at or around an intersection of a path of illumination from the light source with a plane corresponding to the panel and defining a view region having transparency values greater than those of surrounding regions. Mapping 3010 may associate the view pattern to at least one panel region 110, and configuring 3020 may set the transparency of the at least one panel region 110 in accordance with the view region so that illumination passes through the panel 100 toward the surface while surrounding panel regions 110 remain at lower transparency to improve contrast.

[0290] The light source may include, without limitation, a digital projector, a spotlight with patterned optics (e.g., gobo), a laser projector, or natural daylight (e.g., sunlight modeled as a distant source with a known direction). The projected image may be formed by the light source itself (e.g., by spatial modulation within the projector or by upstream optics), with the view region acting as a transmissive aperture aligned to the beam. A characteristic size of the view region may be selected according to the beam footprint at the panel, for example based on standoff distance and beam divergence, and edges may be softened to reduce visible discontinuities at panel-region boundaries. Where the light source or its aim changes, the transparency map may be updated 3120 so that the view region remains centered relative to the movingintersection, maintaining projection on the surface. Non-limiting examples include: a projector on a first side projecting a logo through the panel 100 onto a wall on a second side, where the view region is centered at the beam intersection; a spotlight projecting text onto a floor, with the view region following pan / tilt adjustments; or sunlight admitted along a computed solar direction to project a patterned illumination onto an interior surface, with the view region translated over time as the solar angle changes.

[0291] Reference is now made to the drawings in which the activity diagram of Figure 18 depicts an exemplary method 3000 providing coordinated views across two multi-region selective-opacity panels 100 / 100', in accordance with the teachings of the present invention.

[0292] The multi-region selective-opacity panel 100 may be a first multi-region selective-opacity panel 100 and a first view may be configured thereon (for example, by rendering 3115 a view pattern in a transparency map and configuring 3020 the transparency of at least one panel region 110 corresponding to the view pattern). A second view may be configured 3160 by adjusting a second transparency of at least one panel region 110 of a second multi-region selective-opacity panel 100', thereby allowing an at least partial visibility from the position of interest 190 across the first multi-region selective-opacity panel 100 and the second multi-region selective-opacity panel 100'. Locating the second view may include applying a registration between coordinate frames of the first and second panels so that the second view is positioned on the second panel 100' in a manner consistent with the first view on the first panel 100, while maintaining that transparency values within each view region are greater than those of surrounding regions. The second view may employ any of the shapes described herein (e.g., circular, vertical, horizontal, or person shaped), and a characteristic size of the second view may be selected the same as, or different from, the first view to accommodate spacing and parallax between the panels.

[0293] In further embodiments, the first and second panels 100 / 100' may be separated by a standoff distance selected according to the installation, for example about 10 mm to about 2 m, optionally about 50 mm to about 500 mm. A calibration transform may be established between the panels so that mapping 3010 of the view patterns accounts for panel spacing, relative orientation, and lateral offset. Configuring 3020 the transparencies on both panels may be performed substantially concurrently so that at least partial visibility is provided from the position of interest 190 across both views while surrounding panel regions 110 remain at lower transparency for privacy or shading. Where the position of interest 190 moves, the transparency map may be updated 3120 and, if applicable, view alignment may be maintained across both panels by translating and / or resizing the first and second views in accordance with the registration.

[0294] By way of illustration, a first multi-region selective-opacity panel 100 may be an exterior glazing and a second multi-region selective-opacity panel 100' may be an interior partition; a first view may be configured on the exterior glazing and a second view may be configured 3160 on the interior partition so that an observer at the position of interest 190 is provided at least partial visibility across both panels.As another illustration, a first panel 100 and a second panel 100' may be two smart-glass doors along a corridor; coordinated first and second views may be configured so that visibility is provided along an intended sight path while adjacent regions remain at lower transparency.

[0295] Reference is now made to the drawings in which the activity diagram of Figure 19 depicts an exemplary method 3000 providing aligned views across two multi-region selective-opacity panels 100 / 100', in accordance with the teachings of the present invention.

[0296] The position of interest 190 may be a first position of interest 190 located on a first side of a first multi-region selective-opacity panel 100, and a second position of interest 192 may be obtained 3170 on an opposite side of a second multi-region selective-opacity panel 100'. A line of sight 195 from the first position of interest 190 towards the second position of interest 192 may be computed 3175, the line of sight 195 comprising a first intersection at the first multi-region selective-opacity panel 100 and a second intersection at the second multi-region selective-opacity panel 100'. The first and second intersections may be determined by representing the line of sight 195 parametrically between the two positions and solving ray-plane intersections with planes corresponding to the first and second panels; intersections may be clipped to panel extents and expressed in transparency-map coordinates for each panel.

[0297] A first view region may be located relative to the first intersection and a second view region may be located relative to the second intersection, allowing at least partial visibility between the first position of interest 190 and the second position of interest 192 across the first view region and the second view region. Locating may include rendering 3115, in respective transparency maps, view patterns centered at or around the first and second intersections, each view pattern defining a view region having transparency values greater than those of surrounding regions. Mapping 3010 may associate each view pattern to at least one panel region 110 of the corresponding panel 100 / 100', and configuring 3020 may set the transparency of the at least one panel region 110 in accordance with the transparency values of the respective view region so that the two view regions are co-registered along the computed line of sight 195.

[0298] A registration between coordinate frames of the first and second panels 100 / 100' may be established (e.g., a rigid transform including relative translation and rotation) so that the first and second intersections and corresponding view regions remain aligned despite panel spacing and / or non-parallel orientations. Characteristic sizes of the first and second view regions may be selected according to application constraints, including panel spacing, expected localization tolerance, and desired field of view, and may be equal or different between the two panels. Any of the shapes described herein may be employed for each view region (e.g., circular, vertical, horizontal, or person shaped), optionally with softened edges to reduce visible discontinuities at panel-region boundaries, while maintaining that transparency values within each view region are greater than those of surrounding regions.

[0299] Optionally, when either of the positions of interest moves, the transparency maps may be updated so that the first and second view regions translate and / or resize to remain located relative to the updated intersections, thereby maintaining at least partial visibility between the first position of interest 190 and the second position of interest 192 across the two panels.

[0300] The first position of interest 190 may be an observer and the second position of interest 192 may be an observee, and the at least partial visibility across the first view region and the second view region may allow the observer to see the observee. In such embodiments, a first view region may be located relative to an intersection of a computed line of sight 195 with a first multi-region selective-opacity panel 100, and a second view region may be located relative to a corresponding intersection with a second multi-region selective-opacity panel 100'. Mapping 3010 may associate each view pattern to panel regions 110 of the respective panels, and configuring 3020 may set the transparency of those panel regions 110 so that each view region has transparency values greater than those of surrounding regions. When the first and second view regions are co-registered along the line of sight 195, optical rays from the observee may traverse both view regions with reduced attenuation and reach the observer, thereby providing at least partial visibility through the first and second panels. Optional updates 3120 may translate and / or resize the view regions when either the observer or the observee moves, maintaining alignment and the ability of the observer to see the observee.

[0301] In one embodiment, multiple view regions may be rendered concurrently in the transparency map, each located relative to a corresponding position of interest 190, while maintaining for each that transparency values within its view region are greater than those of surrounding regions. Arbitration among multiple positions of interest may include at least one of: selecting a primary position of interest 190; rendering a union of multiple view regions; and time-multiplexing among view regions at an update cadence consistent with panel response. Priority rules may be configured to favor specific users, locations, or schedules.

[0302] In one embodiment, a view region may be formed by a composition of the shapes described herein, including a combination of a circular pattern with a vertical or horizontal pattern, or a person shaped pattern with a circular pattern to enlarge a field around a silhouette. Compositions may be rendered with feathered edges to reduce visible discontinuities and mapped to panel regions as described herein.

[0303] In one embodiment, a calibration transform may be established between sensing or localization frames and a panel-relative coordinate frame so that positions of interest, sight directions, and line-of-sight intersections remain registered to the multi-region selective-opacity panel 100. For panels that are curved, tilted, or installed with lateral offsets, mapping to transparency-map coordinates may be performed using an affine, projective, or spline-based transform so that view regions are positioned and sized as intended over the panel surface.

[0304] In one embodiment, edge handling may include clipping view regions to panel extents and avoiding fixed keep-out zones such as perimeter busbars or hardware features. Anti-aliasing and feathering may be applied at view-region boundaries prior to mapping so that configured transitions appear smooth across panel-region boundaries. Where the achievable set of transparency states is discrete, spatial and / or temporal dithering may be used while maintaining a substantially zero-mean AC drive as described herein.

[0305] In one embodiment, update behavior may include double-buffering of control data such that transparency changes occur coherently across panel regions 110. Update cadence may be selected in view of panel response times so that tracking of positions of interest appears smooth while avoiding excessive toggling. When a tracked position of interest 190 cannot be determined reliably, a fail-safe behavior may be applied, including holding the last valid configuration for a defined interval, shrinking a view region toward a minimum aperture, or reverting affected panel regions 110 toward a lower transparency.

[0306] In one embodiment, per-region calibration may be applied so that configured transparency values compensate for region-to-region variation and temperature effects. Calibration may be expressed as per-region lookup tables or parametric corrections applied after rendering but before mapping to drive values, while preserving the monotonic relationships described herein for distance-dependent size and transparency.

[0307] In one embodiment, application policies may constrain view formation, including a maximum total transmissive area across the panel, a minimum / maximum aperture for any view region, or ambient-light-adaptive scaling of transparency values, while maintaining that each view region has transparency values greater than those of surrounding regions. Where energy, glare, or privacy requirements dictate, transparency outside view regions may be biased toward lower values and view-region sizes or transparencies may be attenuated in bright conditions.

[0308] For greater clarity, specific details and examples are provided hereinbelow related to obstructions, but a person skilled in the art will readily understand that the teachings presented hereinabove, related to rendering views using a multi-region selective-opacity panel 100, may also be applied, with adaptation.

[0309] Reference is now made to the drawings in which the activity diagram of Figure 20 depicts an exemplary method 3000 for obstructing a view using a multi-region selective-opacity panel 100, in accordance with the teachings of the present invention.

[0310] In one embodiment, the correspondence, mapping 3010, configuring 3020, resampling, calibration, and update techniques described for the view embodiments are applied with adaptations thatwill be apparent to a person skilled in the art. In particular, an obstruction pattern rendered 3220 in a transparency map defines an obstruction region having transparency values lower than those of surrounding regions, and configuring 3020 sets panel regions 110 corresponding to the obstruction region toward lower transparency (at least partially scattering) relative to surrounding regions. Where the view embodiments increased transparency within a view region to create see-through capability, the obstruction embodiments decrease transparency within an obstruction region to attenuate visibility or illumination along selected sight paths.

[0311] In one embodiment, the same pattern shapes used for views may be used for obstructions, including a circular pattern, a vertical pattern, a horizontal pattern, and a person shaped pattern, with edges optionally feathered prior to mapping to reduce visible discontinuities at panel-region boundaries. A position of interest 190 may be obtained 3210 relative to the multi-region selective-opacity panel 100, an obstruction pattern may be rendered 3220 in the transparency map located relative to the position of interest 190 with lower transparency values inside the obstruction region than outside, and the transparency map may be updated 3230 when the position of interest 190 moves. Distance- and elevation-dependent behaviors, sight-direction alignment, two-sided line-of-sight alignment, dual-threshold gating, light-source roles, and multi-panel coordination may be implemented analogously to the view embodiments, with the adapted objective of reducing transmission within the obstruction region while maintaining higher transmission in surrounding regions.

[0312] In one embodiment, the position of interest 190 may further include an elevation, and rendering 3220 an obstruction pattern may include locating the obstruction pattern relative to the elevation in the transparency map. The elevation may be expressed as a vertical coordinate of a reference point associated with the position of interest 190 in a panel-relative coordinate frame, obtained for example by transforming a three-dimensional estimate into the panel frame and extracting a component along a defined vertical axis, by computing a height above a baseline such as a bottom edge of the panel, or by estimating a floor plane and taking the orthogonal distance from the reference point to that plane. Locating the obstruction pattern relative to the elevation may include selecting rows or vertically distributed panel regions 110 corresponding to an elevation band around the measured height and assigning lower transparency values within that band than in surrounding regions so that visibility is attenuated at the relevant height. By way of illustration, a person shaped obstruction may be positioned higher for a standing observer and lower for a seated observer, or a horizontal obstruction band may be positioned near an upper elevation to mitigate high-angle glare, while surrounding regions remain at higher transparency.

[0313] In one embodiment, the position of interest 190 may be a position of an observer and the obstruction may prevent the observer from seeing, at least partially, through the multi-region selective- opacity panel 100. Preventing at least partial visibility may include rendering 3220 an obstruction patternlocated relative to the observer's position and configuring 3020 panel regions 110 corresponding to the obstruction region toward lower transparency than surrounding regions, thereby attenuating transmission along the observer's likely sight paths. For example, a vertical obstruction pattern may be rendered along a corridor-facing portion of a panel to block recognition through a doorway, or a person shaped obstruction may be aligned to a detected silhouette on the opposite side to obscure an identity while leaving adjacent regions more transparent for ambient light.

[0314] Reference is now made to the drawings in which the activity diagram of Figure 21 depicts an exemplary method 3000 for obstructing a view at the intersection of an observer's sight direction with a multi-region selective-opacity panel 100, in accordance with the teachings of the present invention.

[0315] In one embodiment, a sight direction of the observer may be obtained 3240 and the obstruction pattern may be located 3245 relative to an intersection of the sight direction with the multiregion selective-opacity panel 100. The sight direction may be represented as a gaze vector from a reference point associated with the observer in a panel-relative coordinate frame. An intersection point may be computed between the gaze vector and a plane corresponding to the panel and converted to transparency-map coordinates. Locating 3245 may include centering an obstruction pattern (e.g., a circular, vertical, horizontal, or person shaped pattern) at or around the intersection so that transparency values within the obstruction region are lower than those of surrounding regions. Mapping 3010 may associate the obstruction pattern to at least one panel region 110, and configuring 3020 may set those panel regions 110 toward an at least partially scattering configuration, thereby reducing visibility along the sight direction. Where the sight direction is substantially parallel to the panel plane or the intersection lies near a boundary, a nearest-approach or clamped intersection may be used, and temporal smoothing may be applied to limit flicker during small eye or head movements.

[0316] In one embodiment, the position of interest 190 may be a position of a light source and the obstruction may prevent the light source from illuminating, at least partially, through the multi-region selective-opacity panel 100. Preventing illumination may include determining a location of the light source relative to the panel and, where available, an aim or beam axis; rendering 3220 an obstruction pattern located relative to a path of illumination from the light source to the panel; and configuring 3020 panel regions 110 corresponding to the obstruction region toward lower transparency so that flux transmitted along the path is attenuated. Non-limiting examples include rendering a horizontal obstruction band aligned to a solar direction to reduce direct sun penetration while leaving other areas more transparent, rendering a circular obstruction centered at a headlight aim to mitigate glare, or rendering a shaped obstruction to suppress projected content from a nearby projector. Where the light source moves or its aim changes, the transparency map may be updated 3230 so that the obstruction pattern remains located relative to the current path of illumination.

[0317] Reference is now made to the drawings in which the activity diagram of Figure 22 depicts an exemplary method 3000 for obstructing a view aligned to a computed line of sight 195 between positions on opposite sides of a multi-region selective-opacity panel 100, in accordance with the teachings of the present invention.

[0318] In one embodiment, the position of interest 190 may be a first position of interest 190 located on a first side of the multi-region selective-opacity panel 100, and a second position of interest 192 may be obtained 3250 on a second side of the multi-region selective-opacity panel 100. A line of sight 195 from the first position of interest 190 to the second position of interest 192 may be computed 3255, the line of sight 195 comprising an intersection at the multi-region selective-opacity panel 100. The first and second positions of interest may be expressed in a panel-relative coordinate frame; the line of sight 195 may be represented parametrically, and the intersection with a plane corresponding to the panel may be computed and clipped to panel extents, then converted to transparency-map coordinates. Where the computed line of sight 195 is substantially parallel to the panel plane or does not intersect within the panel boundary, a nearest-approach or clamped intersection consistent with the application may be used.

[0319] In one embodiment, the obstruction pattern may be located relative to the intersection of the line of sight 195 at the multi-region selective-opacity panel 100. Locating may include rendering 3220 an obstruction pattern centered at or around the intersection in the transparency map, the obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions. Mapping 3010 may associate the obstruction pattern to at least one panel region 110, and configuring 3020 may set the transparency of the at least one panel region 110 in accordance with the obstruction region so that transmission along the computed sight path is attenuated while surrounding regions remain at higher transparency. Any of the shapes described herein may be used for the obstruction pattern, including a circular pattern, a vertical pattern, a horizontal pattern, and a person shaped pattern, with characteristic size selected according to the installation and edges optionally feathered to reduce visible discontinuities at panel-region boundaries.

[0320] In one embodiment, the obstruction pattern may be updated 3260 when the second position of interest 192 moves. Updating 3260 may include re-acquiring the second position of interest 192 on the second side, re-computing 3255 the line of sight 195 from the first position of interest 190 to the second position of interest 192, determining an updated intersection with the panel 100, and relocating the obstruction pattern relative to the updated intersection. Mapping 3010 and configuring 3020 may then be repeated so that panel regions 110 corresponding to the relocated obstruction region are set toward lower transparency and previously affected regions are returned toward higher transparency. Temporal filtering, hysteresis, or rate limiting may be applied so that the obstruction tracks motion smoothly while respecting panel response times. By way of illustration, an obstruction may follow a moving person on the far side toprevent recognition through the panel, or may track a moving target point so that a light source on the near side is prevented from illuminating through along the changing path.

[0321] In one embodiment, the position of interest 190 may be a first position of interest 190 located on a first side of the multi-region selective-opacity panel 100 and a second position of interest 192 may be obtained on a second side of the multi-region selective-opacity panel 100, the first position of interest 190 including a first distance relative to the panel and the second position of interest 192 including a second distance relative to the panel. Configuring 3020 may include adjusting at least one panel region 110 of the multi-region selective-opacity panel 100 from an at least partially transmissive configuration to an at least partially scattering configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold. The first and second distances may be defined consistently with the intended behavior, including a perpendicular distance to a plane corresponding to the panel, a range measured along a computed line of sight 195 from each position to the panel plane, or a shortest Euclidean distance to a selected panel-region footprint embedded in three-dimensional space. The distances may be obtained by sensing or localization and expressed in a panel-relative coordinate frame; temporal filtering and hysteresis may be applied prior to threshold evaluation to reduce oscillation near threshold values.

[0322] In one embodiment, the first and second distance thresholds may be configurable according to application requirements, for example within about 0.3-5.0 m, optionally about 0.5-2.0 m, and may be asymmetric. When both distances satisfy their respective thresholds, panel regions 110 corresponding to an obstruction pattern located relative to an intersection of the relevant sight path with the panel may be set toward lower transparency (at least partially scattering); when either distance does not satisfy its threshold, the affected panel regions 110 may be maintained at, or returned toward, higher transparency. Intermediate behaviors may be used, including shrinking the obstruction region or reducing its opacity as either distance approaches its threshold from within, while preserving the requirement that transparency values within the obstruction region remain lower than those of surrounding regions.

[0323] By way of illustration, a corridor privacy application may obtain a first position of interest 190 corresponding to an observer on one side and a second position of interest 192 corresponding to an observee on the other side. When both are within configured proximity thresholds, an obstruction pattern centered at the intersection of the line of sight 195 may be mapped 3010 and configured 3020 so that panel regions 110 along that path are transitioned toward an at least partially scattering configuration, preventing recognition through the panel. As another illustration, a glare-control scenario may treat a headlight as the first position of interest 190 and a protected interior task area as the second position of interest 192; when both standoffs fall within thresholds, an obstruction pattern located at the intersection may be configured to attenuate illumination along that path.

[0324] Reference is now made to the drawings in which the activity diagram of Figure 23 depicts an exemplary method 3000 providing coordinated obstructions, and the drawing of Figure 34 depicts an exemplary arrangement in which an obstruction is used to cast a shadow at a specific location, in accordance with the teachings of the present invention.

[0325] In one embodiment, the position of interest 190 may be a light source located on a first side of the multi-region selective-opacity panel 100, and an obstruction region may be used to project a shadow onto a surface located on a second side of the panel. Obtaining 3210 the position of interest 190 may include determining a location of the light source relative to the panel and, where available, an aim or beam axis expressed in a panel-relative coordinate frame. Rendering 3220 an obstruction pattern may include locating the obstruction pattern at or around an intersection of a path of illumination from the light source with a plane corresponding to the panel, the obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions. Mapping 3010 may associate the obstruction pattern to at least one panel region 110, and configuring 3020 may set the transparency of the at least one panel region 110 in accordance with the obstruction region so that flux transmitted along the illumination path is attenuated, thereby casting a shadow on the surface on the second side. Surrounding panel regions 110 may be maintained at higher transparency to preserve ambient light.

[0326] In one embodiment, the shape of the obstruction pattern may correspond to a desired shadow silhouette on the surface, including a circular pattern, a vertical pattern, a horizontal pattern, or a person shaped pattern, with edges optionally feathered prior to mapping to reduce visible discontinuities at panel-region boundaries. A characteristic size of the obstruction region may be selected according to the beam footprint at the panel and the standoff and orientation of the surface, and may be adjusted so that the projected shadow occupies a target area on the surface. Where the light source moves or its aim changes, or where the surface location changes, the transparency map may be updated 3230 so that the obstruction region remains located relative to the current illumination path, maintaining the intended shadow placement.

[0327] By way of illustration, a spotlight on a first side may be partially occluded by a circular obstruction region centered at the beam intersection with the panel so that a circular shadow appears on a wall or floor on the second side. As another illustration, a horizontal obstruction band aligned to a solar direction may be configured across the panel so that sunlight is selectively attenuated and a shading band is projected onto an interior work surface. In each case, panel regions 110 corresponding to the obstruction region are configured toward an at least partially scattering state to reduce transmission along the path, while regions outside the obstruction region remain more transmissive.

[0328] In one embodiment, the multi-region selective-opacity panel 100 may be a first multi-region selective-opacity panel 100, and a first obstruction may be configured thereon (for example, by rendering3220 an obstruction pattern in a transparency map and configuring 3020 at least one panel region 110 corresponding to the obstruction region to lower transparency than surrounding regions). A second obstruction pattern may be rendered 3270 by adjusting a transparency of at least one panel region 110 of a second multi-region selective-opacity panel 100', thereby preventing a complete visibility from the position of interest 190 across the first multi-region selective-opacity panel 100 and the second multiregion selective-opacity panel 100'. In one embodiment, locating the second obstruction pattern may include applying a registration between coordinate frames of the first and second panels 100 / 100' so that the second obstruction region is positioned on the second panel 100' in a manner consistent with the first obstruction region on the first panel 100, taking into account panel spacing, relative orientation, and lateral offset. Any of the shapes described herein may be used for each obstruction pattern (e.g., circular, vertical, horizontal, or person shaped), with characteristic sizes selected according to the installation, and edges optionally feathered prior to mapping 3010 to reduce visible discontinuities at panel-region boundaries. In one embodiment, prevention of complete visibility may be achieved by configuring 3020 the first and second obstruction regions so that combined transmission along likely sight paths is reduced below a target contrast threshold, while surrounding regions remain at higher transparency to admit ambient light. By way of illustration, a vestibule with two smart-glass doors may employ coordinated first and second obstructions centered along an expected sight corridor so that a person on one side cannot see through both doors, or a storefront and interior partition may employ aligned obstructions to block direct lines of sight while allowing general daylighting elsewhere.

[0329] Reference is now made to the drawings in which the activity diagram of Figure 24 depicts an exemplary method 3000 providing aligned obstructions across two multi-region selective-opacity panels 100 / 100' based on a computed line of sight 195 between positions on opposite sides, in accordance with the teachings of the present invention;

[0330] In one embodiment, the position of interest 190 may be a first position of interest 190 located on a first side of a first multi-region selective-opacity panel 100, and a second position of interest 192 may be obtained 3280 on an opposite side of a second multi-region selective-opacity panel 100'. A line of sight 195 from the first position of interest 190 towards the second position of interest 192 may be computed 3285, the line of sight 195 comprising a first intersection at the first multi-region selective-opacity panel 100 and a second intersection at the second multi-region selective-opacity panel 100'. The intersections may be determined by representing the line of sight 195 parametrically between the two positions and solving ray-plane intersections with planes corresponding to the first and second panels; intersections may be clipped to panel extents and expressed in respective transparency-map coordinates.

[0331] In one embodiment, a first obstruction region may be located relative to the first intersection and a second obstruction region may be located relative to the second intersection, thereby preventing acomplete visibility between the first position of interest 190 and the second position of interest 192 across the first obstruction region and the second obstruction region. Locating may include rendering 3220, in respective transparency maps, obstruction patterns centered at or around the first and second intersections, each obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions. Mapping 3010 may associate each obstruction pattern to at least one panel region 110 of the corresponding panel 100 / 100', and configuring 3020 may set the transparency of those panel regions 110 toward an at least partially scattering configuration so that transmission along the computed sight path is attenuated at both panels. A registration between coordinate frames of the first and second panels 100 / 100' may be established so that the obstruction regions remain co-registered along the line of sight 195 despite panel spacing and / or non-parallel orientations. Characteristic sizes and shapes (e.g., circular, vertical, horizontal, or person shaped) may be selected according to application constraints while maintaining that transparency values within each obstruction region are lower than those of surrounding regions.

[0332] In one embodiment, the first position of interest 190 may be an observer and the second position of interest 192 may be an observee, and preventing complete visibility across the first obstruction region and the second obstruction region may prevent the observer from seeing the observee. In such an arrangement, obstruction patterns may be rendered 3220 and located relative to respective intersections of a computed line of sight 195 with a first multi-region selective-opacity panel 100 and a second multiregion selective-opacity panel 100', each obstruction region having transparency values lower than those of surrounding regions. Mapping 3010 and configuring 3020 may set panel regions 110 within the first and second obstruction regions toward an at least partially scattering configuration so that transmission along the line of sight 195 is attenuated at both panels, thereby reducing scene luminance and contrast at the observer below recognition thresholds while maintaining higher transparency in surrounding regions. Where either the observer or the observee moves, updates 3230 may relocate and / or resize the obstruction regions to remain aligned to the recomputed intersections and continue preventing complete visibility.

[0333] A fourth aspect of the techniques described herein relates to a Polymer-Dispersed Liquid Crystal (PDLC) system 5000. As depicted in Figure 25, a power source 120 and a ground connection 122 are arranged to drive one or more PDLC regions 110 of a PDLC panel 100, each region 110 having a front side 112 with an input conductive coating and a back side 116 with a ground conductive coating. The PDLC system 5000 may include a power source 120, a ground connection 122 and a PDLC panel 100. The PDLC panel 100 may include one or more PDLC regions 110, each PDLC region 110 with a front side 112 covered with an input conductive coating, a back side 116 covered with a ground conductive coating, an input gate 114 to selectively connect the input conductive coating to the power source 120, and adraining gate 118 configured to selectively connect the input conductive coating to the ground connection 122. With the input gate 114 closed and the draining gate 118 open, the input conductive coating may be charged, causing the PDLC region 110 to transition into a first transparency state. With the input gate 114 open and the draining gate 118 closed, charge may be drained from the input conductive coating, causing the PDLC region 110 to transition into a second transparency state. One of the first transparency state and the second transparency state may be an at least partially transmissive state and the other may be an at least partially scattering state. Optionally, the PDLC region 110 may transition into the second transparency state within 50 ms after the draining gate 118 is closed. Optionally, the input gate 114 and the draining gate 118 may form a half-bridge between a supply rail of the power source 120 and the ground connection 122, a switching node of the half-bridge being electrically coupled to the input conductive coating.

[0334] In one embodiment, charging of the input conductive coating with the input gate 114 closed establishes an electric field across the PDLC region 110 between the input conductive coating at the front side 112 and the ground conductive coating at the back side 116, thereby causing the region 110 to transition into a first transparency state. In another embodiment, actively connecting the input conductive coating to the ground connection 122 by closing the draining gate 118 after opening the input gate 114 may discharge residual charge and collapse the field so that the PDLC region 110 transitions into a second transparency state. Depending on material formulation, one of these states may correspond to an at least partially transmissive condition and the other to an at least partially scattering condition; reverse-mode materials may be accommodated by the same gating sequence with an inversion of which state is transmissive versus scattering.

[0335] In one embodiment, active draining via the draining gate 118 may accelerate return toward the second transparency state relative to passive decay, and the PDLC region 110 may transition into the second transparency state within 50 ms after the draining gate 118 is closed. The discharge path impedance, region capacitance, and device ratings may be selected so that rapid discharge is achieved without overstress, while the back side 116 remains referenced to the ground connection 122.

[0336] In one embodiment, the input gate 114 and the draining gate 118 may form a half-bridge between a supply rail of the power source 120 and the ground connection 122, a switching node of the half-bridge being electrically coupled to the input conductive coating. Non-overlap (dead-time) may be provided between the turn-off of one gate and the turn-on of the other to limit shoot-through currents. The gates may be implemented using solid-state switches (e.g., MOSFETs) with suitable gate-drive circuitry, and a small series impedance at the switching node may be used to moderate inrush and ringing while maintaining the desired charging and draining functions.

[0337] In one embodiment, the gates 114 / 118 may be located on a driver board within a perimeter frame and connected to the panel 100 via short interconnects to the input conductive coating and the ground conductive coating. In another embodiment, at least one of the gates 114 / 118 may be integrated on or within a panel substrate proximate to the PDLC region 110, enabling a panel device in which per-region switching is incorporated at the substrate level while external connections provide the supply rail, the ground connection 122, and control signals.

[0338] In one embodiment, the ground conductive coating at the back side 116 of each PDLC region 110 may be bonded to the ground connection 122 through a low-impedance path to stabilize region potential and to provide a defined reference during both charging and draining. Mechanical and environmental integration of the gates and interconnects may be selected to preserve optical quality of the panel 100 while ensuring reliable electrical connection to the input conductive and ground conductive coatings.

[0339] The input conductive coating may be driven by an alternating current (AC) signal. The AC signal may be substantially zero-mean so that long-term ionic migration and charge accumulation within the PDLC stack are mitigated. The AC waveform may be sinusoidal, square, trapezoidal, and / or PWM-shaped while maintaining DC balance. A drive frequency may be selected for optical performance and comfort (e.g., to mitigate perceptible flicker), for example about 40-200 Hz, optionally about 60-120 Hz. An effective amplitude (e.g., Vrms) may be selected to achieve a target transparency while observing dielectric and safety limits.

[0340] In one embodiment, the AC signal may be synthesized by a half-bridge that alternately connects the input conductive coating to a positive DC rail and to a negative DC rail referenced to a ground connection 122, thereby producing a bipolar excitation across the PDLC region 110 with the back side 116 grounded. Rails may be maintained within a SELV-like envelope, for example a positive rail below about +57 V and a negative rail above about -57 V. In another embodiment, the AC signal may be generated by an H-bridge, a transformer-coupled driver, or a controller 200 that provides synchronized bipolar outputs, provided that the input conductive coating receives a substantially zero-mean excitation at the selected frequency.

[0341] For safety and compatibility with glazing integration, actuation rails may be maintained within a safe extra-low-voltage (SELV)-like envelope. Industry standards define SELV limits with some variation; accordingly, references herein to example magnitudes (e.g., approximately ±48 V or magnitudes below about 60 V) are illustrative and not limiting. Any rail magnitudes within a low-voltage range suitable for the intended installation and dielectric stack may be used while preserving the substantially zero-mean AC excitation described herein.

[0342] In one embodiment, the AC drive applied to the input conductive coating may be adjusted in amplitude and / or duty while preserving DC balance so that intermediate effective voltages correspond to intermediate transparency states. Gate non-overlap (dead-time), over-current protection, and EMI / ESD suppression may be provided in proximity to the switching elements and panel interconnects, and creepage / clearance may be maintained at panel edges and connectors while the back side 116 remains referenced to the ground connection 122.

[0343] The PDLC system 5000 may further include a controller 200. Two or more phase-shifted alternating current (AC) signals, having a common frequency, may be generated. The two or more phase-shifted AC signals may be distributed to respective front sides 112 of at least two adjacent PDLC regions 110 of the PDLC panel 100. Optionally, the common frequency may be between 60 Hz and 120 Hz.

[0344] In one embodiment, the controller 200 may synthesize multiple AC channels that are phase-offset relative to one another while sharing a stable timing reference so that the common frequency remains the same across channels. Each channel may be routed to the input conductive coating at the front side 112 of a corresponding immediately adjacent PDLC region 110, while back sides 116 remain referenced to the ground connection 122, thereby reducing instantaneous potential differences at shared boundaries and mitigating fringe-field coupling or visible crosstalk. As depicted in Figure 35, the phase offsets may be selected according to panel geometry and adjacency relationships and may be maintained over time by synchronization of the controller's outputs. The common frequency may be selected for optical performance and comfort (e.g., to mitigate perceptible flicker), for example within about 60-120 Hz, with channel amplitudes calibrated so that adjacent regions receive substantially equivalent effective drive when set to comparable transparency states. In further embodiments, generation of the phase-shifted channels may be implemented using multi-output oscillators, digitally synthesized waveforms with a shared clock, or synchronized driver stages that preserve the commanded phase relationships during distribution to the panel interconnect.

[0345] The two or more phase-shifted AC signals may be uniformly phase-spaced from one another.

[0346] In one embodiment, for N channels the phase offsets may be approximately 360° / N apart (e.g., 180° for two channels, 120° for three channels, 90° for four channels, 72° for five channels), maintained relative to a shared timing reference so that the common frequency remains equal across channels. In one embodiment, uniform spacing may be preserved within a tolerance over temperature and load (for example, within a few electrical degrees), with amplitude matching among channels so that adjacent PDLC regions 110 driven to comparable transparency states receive substantially equivalent effective drive. In one embodiment, the uniformly phase-spaced set may be assigned across immediately adjacent regions so that neighboring regions are driven on different phases, thereby reducingsimultaneous potential differences at shared boundaries, moderating instantaneous aggregate current, and improving boundary uniformity. In one embodiment, the controller 200 may implement uniform phase spacing using digitally synthesized waveforms locked to a common clock or by multi-output oscillators with controlled phase relationships, with periodic resynchronization to maintain the intended uniform phase spacing over time.

[0347] The power source 120 may include a positive Direct Current (DC) supply and a negative DC supply. The controller 200 may be configured to generate the two or more phase-shifted AC signals by alternating between the positive DC supply and the negative DC supply, to balance a load of the two or more phase-shifted AC signals across the positive DC supply and the negative DC supply.

[0348] The positive and negative supplies may be referenced to a ground connection 122 such that the back side 116 remains at ground potential while the front side 112 of each PDLC region 110 is alternately driven toward the positive rail and toward the negative rail. A per-channel switching stage (e.g., a half-bridge) may connect the input conductive coating to +Vdc during one half-cycle and to -Vdc during the opposite half-cycle, thereby producing a substantially zero-mean bipolar excitation at the common frequency. Equal or controlled dwell times on each rail may ensure that, over time, each channel draws comparable charge from the positive and negative supplies.

[0349] With multiple phase-shifted channels, the controller 200 may interleave the phases so that, at any given instant, a subset of channels is sourcing from the positive rail while another subset is returning current to the negative rail. This interleaving, combined with alternating polarity on each channel, may balance average load between the rails, reduce DC bus ripple, and moderate thermal stress in the power conversion and energy-storage components. Dead-time between complementary switching events, current limiting, and gate-drive synchronization may be provided so that alternating between the rails is achieved without shoot-through and while maintaining the commanded phase relationships across channels.

[0350] A variety of realizations may be used to provide the positive and negative DC supplies, including a split-rail converter with a regulated midpoint reference or separate isolated converters referenced to a common ground, provided that the controller 200 alternates each channel between the positive and negative rails to synthesize the phase-shifted AC drive and to balance loading across the rails.

[0351] The positive DC supply may be below 57 volts and the negative DC supply may be greater than -57 volts. Rails maintained within this SELV-like envelope may limit touch voltage and simplify insulation, creepage, and clearance requirements at panel edges and connectors while providing sufficient headroom to achieve the desired effective drive (e.g., Vrms) at the input conductive coating. By way ofexample, split rails at approximately ±48 V or ±36 V may be used while preserving a substantially zero-mean AC excitation across the PDLC region 110 with the back side 116 referenced to the ground connection 122.

[0352] The PDLC system 5000 may further include a voltage modulator 210 electrically connectable between the controller 200 and the input conductive coating of at least one PDLC region 110. The voltage modulator 210 may modulate an effective voltage of an AC drive signal delivered to the input conductive coating in accordance with an opacity response curve of the at least one PDLC region 110. The controller 200 may provide AC drive signals. The opacity response curve may relate a target optical state (e.g., transmittance / opacity) to an effective drive parameter (e.g., Vrms at a selected AC frequency) and may be realized as a per-panel or per-region lookup table or parametric mapping with optional temperature compensation. The voltage modulator 210 may implement the mapping by adjusting the portion of each AC cycle delivered to the region and / or by scaling amplitude while preserving DC balance and the common drive frequency, thereby producing a commanded effective voltage at the front side 112. The voltage modulator 210 may be provided per region controller 220 or shared across a group of regions, and may be located on a driver board within a perimeter frame or proximate to panel terminations, provided that the modulated AC drive presented to the input conductive coating conforms to the opacity response curve while the back side 116 remains referenced to the ground connection 122.

[0353] Optionally, the voltage modulator 210 may include a Pulse Width Modulation (PWM) module 212 to apply PWM gating to the AC drive signal to generate a PWM modulated AC drive signal. Optionally, the voltage modulator 210 may further include a low-pass filter 214 configured to filter the PWM modulated AC drive signal.

[0354] The PWM module 212 may interrupt the AC drive with a carrier in a range of about 1-100 kHz, optionally about 5-50 kHz, with duty cycle limits of about 5-95%, while maintaining DC balance so that the time-average over each full AC period remains substantially zero-mean. Gating may be applied symmetrically over positive and negative half-cycles and may be phase-aligned to AC zero crossings to reduce distortion and audible artifacts. Duty resolution may be calibrated so that incremental duty changes correspond to incremental effective voltage changes consistent with the opacity response curve.

[0355] The low-pass filter 214 may be implemented as an RC, RL, or LC network with a cutoff frequency selected above the AC fundamental and well below the PWM carrier, thereby attenuating switching components while passing the intended AC excitation. Damping or snubber elements may be included to control ringing during switching transitions. The PWM module 212 and low-pass filter 214 may be provided per region controller 220 or shared among a group of PDLC regions 110, and may be located on a driver board within a perimeter frame or proximate to panel terminations, provided that the filtered,PWM-modulated AC signal delivered to the input conductive coating achieves the commanded effective voltage while preserving a substantially zero-mean drive across the PDLC region 110.

[0356] The controller 200 may provide AC drive signals. The PDLC panel 100 may include a plurality of PDLC regions 110. The PDLC system 5000 may include a communication module 250 and a plurality of region controllers 220, each being electrically connected to at least one PDLC region 110 and being addressable by a region identifier. Each region controller 220 may modulate an AC drive signal according to a region configuration to drive the PDLC region 110 corresponding to the region identifier. The communication module 250 may receive a configuration stream comprising the region identifier and the region configuration, and may transmit the region configuration to at least one region controller 220 corresponding to the region identifier. Optionally, the configuration stream may be a Digital Multiplex (DMX) data stream.

[0357] The controller 200 may synthesize AC drive signals at a common frequency and distribute per-channel drive to region controllers 220. Each region controller 220 may be coupled to the input conductive coating of its assigned PDLC region(s) 110 and to a ground reference, and may implement per-region modulation (e.g., effective amplitude scaling and / or PWM gating consistent with an opacity response curve) in accordance with the received region configuration while preserving DC balance and the commanded frequency. Region identifiers may uniquely reference panel regions (e.g., numeric indices, row / column coordinates, or hierarchical addresses), and the communication module 250 may route region configurations only to addressed region controllers 220, optionally buffering configurations for coherent update. The configuration stream may encode, for each region identifier, at least one parameter indicative of a target transparency / opacity and may optionally include transition timing or curve selection; in a DMX embodiment, such parameters may be mapped to one or more DMX channels assigned to the region identifier. The communication module 250 may support upstream / downstream links for daisy-chain topologies and may perform integrity checks (e.g., framing and error detection) before forwarding region configurations to the corresponding region controllers 220, whereupon the modulated AC drive is applied to the input conductive coating of the addressed PDLC region 110 while the back side 116 remains referenced to the ground connection 122.

[0358] The communication module 250 may support serial fieldbuses and IP-based networking, including but not limited to RS-485 / Modbus, CAN, and Ethernet / IP transports carrying UDP / TCP application protocols (e.g., lighting and building-automation control protocols), without limitation to a particular vendor or message format.

[0359] The PDLC regions 110 may be electrically isolated from one another within a transparent conductive coating of the PDLC panel 100. Optionally, the transparent conductive coating may be patterned to form isolation channels in the transparent conductive coating. Optionally, the transparentconductive coating may be laser ablated to form the isolation channels. Optionally, the transparent conductive coating may be disposed on a substrate that is laminated to a PDLC layer.

[0360] Electrical isolation within the transparent conductive coating may define discrete input electrodes on the front side 112 so that neighboring PDLC regions 110 may be driven independently while the back side 116 remains referenced to a common ground conductive coating. Patterning to form isolation channels may remove or render non-conductive selected portions of the transparent conductive coating along region boundaries and around contact pad areas, thereby preventing lateral conduction and reducing fringe-field coupling between adjacent regions. The isolation channels may extend to the panel perimeter or to designated busbar lands so that each input electrode remains electrically separate along its entire routing path.

[0361] Patterning to create the isolation channels may be performed before lamination to the PDLC layer to protect the LC medium from particulates and thermal exposure. Laser ablation may be used to form the isolation channels with controlled line placement and edge quality; suitable laser parameters may be selected according to the coating material and substrate to achieve complete electrical break without excessive substrate damage. Alternative patterning techniques, such as wet or dry etching with masking, lift-off, or mechanical scribing, may also be employed provided that electrical isolation among the PDLC regions 110 is maintained.

[0362] The transparent conductive coating may be disposed on a substrate that is laminated to a PDLC layer so that the patterned input electrodes register to the intended PDLC region layout. Lamination may be carried out under controlled temperature and pressure to achieve intimate bonding, preserve optical clarity, and maintain the electrical separation defined by the isolation channels. A cooperating substrate carrying the ground conductive coating may be assembled on the opposite side to form the back side 116, with alignment such that the isolated input electrodes on the front side 112 correspond to the PDLC regions 110 defined within the laminated stack. Environmental sealing at the perimeter may be provided to protect the patterned interfaces and preserve long-term electrical isolation.

[0363] The transparent conductive coating may include indium tin oxide (ITO) deposited on a polymeric substrate. Optionally, the isolation channels may have a width less than 100 pm and the ITO may have a sheet resistance between 10 Q / sq and 200 Q / sq.

[0364] The polymeric substrate may include, for example, polyethylene terephthalate (PET), polyethylene naphthalate (PEN), or another optically clear, dimensionally stable film suitable for lamination to a PDLC layer. ITO may be deposited by sputtering (e.g., DC or RF magnetron) or another thin-film process to achieve a target optical transmission and sheet resistance compatible with regional drive uniformity and low visual impact. A sheet resistance within about 10-200 Q / sq may provide an acceptablebalance between lateral voltage uniformity across a PDLC region 110 and overall panel transmittance, with thickness and post-deposition anneal conditions selected accordingly.

[0365] Isolation channels patterned in the ITO may be formed with widths less than about 100 pm to reduce inactive area while ensuring complete electrical separation between adjacent input electrodes. Laser ablation parameters (wavelength, pulse energy, scan speed) may be chosen to remove the ITO cleanly with minimal substrate damage and edge roughness; alternative patterning methods, such as wet or dry etching with masking or lift-off, may be employed where process flow favors those techniques while maintaining sub-100 pm features. Channel continuity and isolation may be verified electrically (e.g., high-impedance measurements across adjacent electrodes) and visually (e.g., microscopy) prior to lamination. The patterned ITO / polymer substrate may then be laminated to the PDLC layer with registration so that the isolated electrodes correspond to intended PDLC regions 110, preserving the electrical isolation defined by the sub-100 pm channels.

[0366] The PDLC panel 100 may include a first transparent conductive layer patterned to define a plurality of PDLC regions 110 and at least one additional transparent conductive layer patterned to form conductive traces routed from a panel perimeter to interior PDLC regions 110. The additional transparent conductive layer may be electrically coupled to the PDLC regions 110 via electrically conductive interconnects at registered contact points. Optionally, the at least one additional transparent conductive layer may be provided on a second substrate laminated to a PDLC layer with a dielectric interlayer therebetween.

[0367] The first transparent conductive layer may be patterned so that discrete input electrodes are formed on the front side 112, each electrode corresponding to one of the PDLC regions 110 and separated from neighboring electrodes by isolation channels. The at least one additional transparent conductive layer may be patterned into narrow traces that originate at the panel perimeter (e.g., at connector or busbar lands) and extend toward interior locations where PDLC regions 110 do not adjoin the perimeter, thereby providing signal distribution to otherwise unreachable regions while preserving optical uniformity in the viewing area.

[0368] Electrically conductive interconnects at registered contact points may be provided where a trace of the additional transparent conductive layer meets the input electrode of a selected PDLC region 110. The dielectric interlayer may be locally opened at each registered contact point, and a conductive path may be formed by at least one of anisotropic conductive film (ACF), conductive epoxy, plated microvias, or deposited metallic bumps so that low-resistance connection is established without compromising optical clarity. Registration features (e.g., fiducials on the substrates) may be used to align the additional transparent conductive layer to the first transparent conductive layer within a tolerance sufficient to place the interconnects entirely on the intended contact pads.

[0369] When the at least one additional transparent conductive layer is provided on a second substrate, the second substrate may be laminated to the PDLC layer with a dielectric interlayer therebetween to electrically isolate the routing traces from the PDLC medium and from the first transparent conductive layer except at the registered contact points. The dielectric interlayer thickness and permittivity may be selected to achieve required isolation and to limit parasitic capacitance, while the lamination process may be controlled to maintain registration and optical flatness. Trace widths, spacings, and sheet resistance of the additional transparent conductive layer may be chosen to balance visibility (e.g., high transmission and low reflectance in the viewing area) with acceptable voltage drop from the panel perimeter to interior PDLC regions 110. Where crossovers are required, further transparent conductive layers separated by additional dielectric interlayers may be used to realize multi-layer routing while maintaining electrical separation and optical performance.

[0370] The PDLC system 5000 may further include a flexible printed circuit board (PCB) 160 electrically connected to the transparent conductive coating. The flexible PCB 160 may connect a power source 120 to respective input conductive coatings of the PDLC regions 110 and may connect a ground connection 122 to respective ground conductive coatings.

[0371] Reference is now made to the drawings in which Figure 36 is a picture of an exemplary flexible Printed Circuit Board (PCB) in accordance with the teachings of the present invention, and Figure 37 is a picture of an exemplary flexible Printed Circuit Board (PCB) in accordance with the teachings of the present invention. The flexible PCB 160 may be arranged along a perimeter of the PDLC panel 100 and may include fine-pitch copper traces on a polymeric film (e.g., polyimide) that fan out from one or more connectors to individual bonding lands aligned to panel contact pads. Dedicated distribution traces may route a supply from the power source 120 to the input conductive coating of each PDLC region 110, and a corresponding return may route the ground connection 122 to the ground conductive coating (e.g., via a ground busbar or discrete ground pads), thereby establishing a defined field across each region during drive. Trace geometry and spacing may be selected to satisfy current-carrying requirements and creepage / clearance constraints at the panel edge while minimizing visual impact in the viewing area. Mechanical features such as relief slots, bend radii, and strain-relief tabs may be provided to accommodate perimeter routing and to protect the electrical joints to the transparent conductive coatings during handling and thermal cycling. Where appropriate, the flexible PCB 160 may also carry identification or low-voltage control conductors, while the primary function remains distribution of the power source 120 to the input conductive coatings and connection of the ground connection 122 to the ground conductive coatings.

[0372] The PDLC system 5000 may further include a frame and a plurality of region controllers 220. The flexible PCB 160 and the plurality of region controllers 220 may be embedded within the frame.

[0373] The frame may be arranged around a perimeter of the PDLC panel 100 and may define internal cavities and raceways to house the flexible PCB 160, region controllers 220, and associated connectors while shielding them from view and environmental exposure. The flexible PCB 160 may be routed along an inner channel of the frame to align bonding lands with panel contact pads, with strain-relief features and clamp points provided by the frame to protect the bonded joints. The region controllers 220 may be mounted on carrier boards or modules retained within frame cavities by bosses, brackets, or rails, with clearance and insulation maintained to satisfy creepage / clearance requirements at the panel edge.

[0374] Thermal management may be facilitated by coupling heat-generating components of the region controllers 220 to thermally conductive portions of the frame (e.g., an aluminum extrusion) through electrically insulating, thermally conductive pads, thereby spreading heat while preserving electrical isolation. Access covers or removable trim segments may be provided to permit service replacement of the flexible PCB 160 and the region controllers 220 without disturbing the panel 100. The frame may further integrate gaskets and seals to limit ingress of dust and moisture to the embedded electronics, and may provide ESD paths and shielding features to manage electrostatic discharge and electromagnetic emissions at the perimeter.

[0375] Power and communication connectors may be located on the frame, with short internal harnesses or direct plug-ins to the embedded region controllers 220 and terminations to the flexible PCB 160. Keyed connectors and labeling may be used to ensure correct mating during installation. By embedding the flexible PCB 160 and the region controllers 220 within the frame, visible wiring is reduced, electrical joints are mechanically protected, and assembly / service operations are simplified while maintaining reliable distribution of the power source 120 and the ground connection 122 to the respective input and ground conductive coatings of the PDLC regions 110.

[0376] The transparent conductive coating may alternatively comprise fluorine-doped tin oxide (FTC) or aluminum-doped zinc oxide (AZO) deposited on glass or polymeric substrates, selected according to optical transmission, environmental durability, and sheet resistance targets compatible with regional drive uniformity. Hybrid transparent conductors, such as silver-nanowire networks or graphene-based films, may be employed where process flow and optical requirements permit, provided that patterning processes yield stable isolation channels and the resulting sheet resistance supports the intended AC drive without excessive lateral voltage drop.

[0377] Logic and communication domains may be galvanically isolated from the ±DC actuation rails to meet safety and electromagnetic compatibility requirements. Isolation may be achieved by isolated DC-DC converters supplying gate-driver and control power, and by digital isolators or opto-isolators on control and telemetry lines. Creepage and clearance across isolation barriers may be selected in accordance with the rail magnitudes (e.g., within a SELV-like envelope of +<57 V and ->-57 V), andcommon-mode chokes, RC snubbers, and transient voltage suppressors (TVS) may be placed at panel interconnects to manage emissions and electrostatic discharge while maintaining a defined ground reference at the back side 116.

[0378] The AC drive presented to the input conductive coating may be synthesized by alternatives to a direct half-bridge while preserving a substantially zero-mean excitation referenced to the ground connection 122. A transformer-coupled push-pull or inverter stage may generate a bipolar waveform on a secondary whose reference is bonded to the ground connection 122, thereby driving the front side 112 relative to the grounded back side 116. Where such coupling is used, the secondary voltage, frequency, and leakage characteristics may be selected so that the commanded AC waveform is delivered without undue distortion and within the dielectric limits of the PDLC stack, and phase synchronization may be maintained across channels in multi-phase embodiments.

[0379] Embedded electronics within the frame may be protected by thin conformal coatings applied to region controller 220 assemblies and by gasketed access covers that provide environmental sealing of frame cavities while preserving airflow or conductive heat paths to thermally managed frame segments. Selective encapsulation (e.g., low-modulus potting of high-voltage terminations) may be used at perimeter joints to enhance mechanical robustness and moisture resistance, provided that thermal dissipation, serviceability of modules, and required creepage / clearance at the panel edge are maintained.

[0380] A fifth aspect of the techniques described herein relates to a Polymer-Dispersed Liquid Crystal (PDLC) retrofit system 6000 as depicted in Figure 26. The PDLC retrofit system 6000 may include a PDLC panel overlay 100 attachable to an exposed surface of a glazing 20 and arranged to present a plurality of PDLC regions 110 that are drivable when electrically coupled at a panel perimeter. An interconnect bus 160 may be disposed along at least one edge of the PDLC panel overlay 100, with electrical coupling between the interconnect bus 160 and respective input conductive coatings of the plurality of PDLC regions 110 so that per-region drive can be delivered from a perimeter location without modification to the glazing 20.

[0381] An edge control module 300 may be connectable to the interconnect bus 160 and may interface the PDLC panel overlay 100 to an external control module 350. The external control module 350 may supply alternating current (AC) power and a data signal to the edge control module 300, and the edge control module 300 may drive the plurality of PDLC regions 110 via the interconnect bus 160 in accordance with the data signal.

[0382] The PDLC panel overlay 100 may be provided as a thin laminated construct sized to the glazing 20, with the plurality of PDLC regions 110 defined within a transparent conductive layer on a front side 112 and a cooperating ground conductive layer on a back side 116. The interconnect bus 160 mayroute conductors from an edge connector to bonding lands aligned with panel contact pads so that the input conductive coatings of respective PDLC regions 110 are electrically coupled at the perimeter. The interconnect bus 160 may be realized by a flexible printed circuit, a flexible flat cable, or a low-profile harness compatible with perimeter mounting; a flexible printed circuit embodiment is described hereinabove in connection with the PDLC system 5000.

[0383] The edge control module 300 may provide terminations for the interconnect bus 160 and may receive AC power and a data signal from the external control module 350. Under control of the data signal, the edge control module 300 may synthesize or switch AC drive on selected conductors of the interconnect bus 160 so that the input conductive coatings of the plurality of PDLC regions 110 are driven in accordance with commanded transparency states while the back side 116 remains referenced to a ground connection 122. The edge control module 300 may thus coordinate distribution of AC drive and application of per-region configurations to the PDLC panel overlay 100 without requiring invasive changes to the glazing 20.

[0384] The external control module 350 may be configured to supply the AC power at a magnitude and frequency appropriate for PDLC operation together with the data signal that conveys region addressing and configuration. The AC power and the data signal may be delivered over separate or combined cabling, provided that the edge control module 300 receives both and, in response, drives the plurality of PDLC regions 110 via the interconnect bus 160 in accordance with the data signal.

[0385] The PDLC retrofit system 6000 may further include an optically clear adhesive and / or a secondary frame retained within a window reveal of the glazing 20. The PDLC panel overlay 100 may be attachable to the glazing 20 using the at least one of the optically clear adhesive and the secondary frame. The optically clear adhesive may comprise a pressure-sensitive optically clear acrylic film configured for dry lamination, a liquid optically clear resin (e.g., UV-curable acrylate) configured for in-situ curing, or an optically clear silicone gel providing compliance for differential thermal expansion, selected to deliver high visible transmittance, low haze, and index-match to reduce interfacial reflections. Surface preparation, alignment features, and controlled bond-line thickness (e.g., spacer beads for films, gap control for liquids) may be employed to preserve optical uniformity across the viewing area. The secondary frame may be a low-profile perimeter carrier captured within the window reveal by non-invasive retention features such as compression gaskets bearing on reveal faces, spring or wedge clips engaging reveal undercuts, or adhesive pads applied to non-viewable lands, thereby forming a capture channel that clamps the PDLC panel overlay 100 without modifying the glazing 20. The frame may incorporate compliant gaskets to distribute clamping pressure, protect edges, and provide a dust / light seal, and may include a concealed raceway for routing the interconnect bus 160 to the edge control module 300.

[0386] The edge control module 300 may be mounted within a perimeter frame of the glazing 20. A carrier bracket or integrated utility recess in a replacement glazing bead may receive the edge control module 300 with snap-in features or captive fasteners while maintaining clearance from the glazing 20 and preserving existing drainage paths. Thermal management may be provided by coupling a heat-spreading baseplate of the edge control module 300 to thermally conductive portions of the perimeter frame through electrically insulating, thermally conductive pads, while environmental protection may be achieved by gasketed covers and con form al -coated electronics. Keyed connectors and strain-relief features may be positioned within the perimeter frame to terminate the interconnect bus 160 and to receive AC power and the data signal from the external control module 350, enabling service access at the frame without disturbing the PDLC panel overlay 100 or the glazing 20.

[0387] A second edge control module 300' may be configured to drive a second PDLC panel overlay 100'. The edge control module 300 may be connectable to the second edge control module 300', and the edge control module 300 and the second edge control module 300' may distribute the data signal such that the second edge control module 300' drives the second PDLC panel overlay 100'. As depicted in Figure 27, upstream and downstream ports of the edge control module 300 may relay the data signal to the second edge control module 300' while the first module 300 consumes only those commands addressed to the PDLC panel overlay 100. The data signal may carry device and / or region identifiers; unconsumed portions may pass through to the second edge control module 300', which then applies region configurations to the second PDLC panel overlay 100' via its interconnect bus 160'. Telemetry collected at each edge control module 300 / 300' may be returned upstream on a supervisory link, enabling monitoring and coordination across multiple overlays.

[0388] The interconnection between the edge control module 300 and the second edge control module 300' may support distribution of the data signal over a daisy-chain topology, with optional pass-through of AC power from an external control module 350 where current capacity and voltage drop constraints are satisfied. Address assignment for each edge control module 300 / 300' may be preconfigured or discovered at power-up so that the data signal is routed deterministically. Integrity checks (e.g., framing and error detection) may be applied before forwarding to maintain reliable distribution of commands across the chain, while each module drives only its associated PDLC panel overlay 100 / 100' in accordance with the received configuration.

[0389] The PDLC panel overlay 100 may be driven according to the method 1000 of the first aspect described hereinabove. In such arrangements, the edge control module 300 may provide alternating-current drive to regions 110 of the PDLC panel overlay 100 while the back side 116 remains referenced to a ground connection 122, and may implement charging and active draining via gated switching consistent with the charging / draining transitions and AC drive teachings previously presented.

[0390] The interconnect bus 160 may be realized by a flexible printed circuit, a flexible flat cable, printed polymer conductors on a transparent or translucent carrier, or a low-profile wire harness routed within a perimeter cover, provided that current-carrying capacity, insulation ratings, and creepage / clearance at the panel edge are maintained. Bonding to panel contact pads may be achieved by anisotropic conductive film, compliant spring contacts retained by the perimeter cover, or conductive adhesives, with strain-relief features to protect the joints during handling and thermal cycling. One or more identification conductors on the interconnect bus 160 may convey panel metadata (e.g., region count, address map, calibration revision) to the edge control module 300 for automatic configuration at installation.

[0391] Alternating current (AC) power and the data signal from the external control module 350 may be delivered over separate cables or combined onto a single trunk. A combined trunk may include separate conductors for power and data within a common jacket or may superimpose a modulated data carrier on the power feed using coupling / decoupling networks at each end, provided that electromagnetic compatibility and isolation requirements are met. The edge control module 300 may include input filtering to recover the data signal without disturbing the AC power quality and to limit conducted and radiated emissions, while surge and ESD protection may be provided on both power and data paths.

[0392] The edge control module 300 may include telemetry and fault-handling functions to support reliable retrofit operation. Per-channel measurements of interconnect-bus voltage and current may be used to estimate load impedance and detect open-circuit or short-circuit conditions to a PDLC region 110. Temperature sensing within the edge control module 300 may enable thermal derating or staged shutdown of affected channels. Detected faults and operating telemetry (e.g., rail voltage, channel currents, module temperature, firmware revision) may be reported upstream to the external control module 350 on a supervisory channel for monitoring, logging, and orchestrating multi-overlay operation.

[0393] The PDLC panel overlay 100 may be configured to conform to mildly curved or irregular glazing 20. Bend-compliant substrates and optically clear adhesives with suitable elongation may be selected so that the overlay conforms within specified minimum bend radii while preserving optical clarity and regional electrical isolation. The secondary frame retained within the window reveal may incorporate compliant gaskets and adjustable clamping to accommodate dimensional tolerances and glazing curvature, while maintaining an unobstructed routing envelope for the interconnect bus 160 at the perimeter.

[0394] Serviceability and environmental protection may be provided at the perimeter. Gasketed access covers integrated into the perimeter frame may permit service access to the edge control module 300 and terminations of the interconnect bus 160 without disturbing the PDLC panel overlay 100 or the glazing 20. Electronics within the frame may be protected by conformal coating of region controllerassemblies and selective encapsulation of high-voltage terminations, while placement of openings and drainage paths may be arranged to preserve the glazing's native drip path and weep holes. Thermal paths from heat-generating components of the edge control module 300 to conductive portions of the frame may be provided through electrically insulating, thermally conductive pads to maintain component temperatures within ratings under expected operating conditions.

[0395] The AC drive provided by the edge control module 300 may be derived from positive and negative DC rails maintained within a SELV-like envelope (e.g., a positive rail below about +57 V and a negative rail above about -57 V) while the back side 116 remains referenced to a ground connection 122. Creepage and clearance at the perimeter frame, within the edge control module 300, and along the interconnect bus 160 may be selected accordingly, and input filtering, EMI / ESD suppression, and over-current / over-temperature protection may be provided at the edge control module 300 and bus terminations. The external control module 350 may supply AC power suitable for generating such rails and the data signal used to configure per-region drive without exceeding the stated envelope.

[0396] A sixth aspect of the techniques described herein relates to a system 7000 for displaying a transparency map using a multi-region selective-opacity panel 100. The system 7000 may include a multiregion selective-opacity panel 100, one or more processors 600, and a controller 200. The multi-region selective-opacity panel 100 may include a plurality of panel regions 110. The one or more processors 600 may map a transparency map region of a transparency map to at least one panel region from the plurality of panel regions 110 and may compute a panel region transparency value in accordance with a transparency value of the transparency map region. The controller 200 may receive control data from the one or more processors 600, the control data including the panel region transparency value for the at least one panel region, and may provide an AC drive signal to the at least one panel region in accordance with the panel region transparency value. As depicted in Figure 28, the one or more processors 600 may be communicatively coupled to the controller 200 to deliver control data comprising panel-region transparency values, and the controller 200 may generate per-region AC drive in accordance therewith. In one embodiment, the processors 600 may include memory, storage, and a network interface to obtain transparency maps, perform mapping and computation of panel-region transparency values, and transmit control data at a cadence coordinated with panel updates; the controller 200 may provide timing, buffering, and per-region actuation while maintaining a substantially zero-mean AC drive.

[0397] The transparency map may be an image, and the transparency map region may be an image region, the transparency value being derived from at least one of a transparency channel, an opacity channel, a luminance channel, and / or a grayscale channel of the image. The processors 600 may interpret such channels to obtain per-region transparency values on a common scale suitable for driving the panel 100 while preserving a monotonic relationship between channel intensity and configured transparency.The plurality of panel regions 110 may be arranged in a regular grid, the image may be a raster image, the image region may be a pixel of the raster image, and the one or more processors 600 may map the pixel to the regular grid. As depicted in Figure 29, pixel-to-grid mapping may be applied so that each panel region 110 is assigned a transparency value derived from corresponding image content.

[0398] The one or more processors 600 may acquire image / video content via local storage or over IP networks and convert such content into transparency-map control data, independent of the specific source protocol or playback device.

[0399] The system 7000 may further include a light source 180. The one or more processors 600 may process the image to obtain one or more intensity channels and a transparency channel and may provide control data to the controller 200 to configure the transparency of the at least one panel region in accordance with the transparency channel. The light source 180 may project light onto the multi-region selective-opacity panel 100 in accordance with the one or more intensity channels under control of the one or more processors 600, as depicted in Figure 30. In such arrangements, the processors 600 may direct the light source 180 per the intensity channels (e.g., color and luminance) while the controller 200 configures regional transmissivity per the transparency channel, thereby forming high-contrast content on selected regions.

[0400] The one or more intensity channels may include a color channel, a luminance channel, and / or a chrominance channel. The processors 600 may convert among color spaces as needed and supply intensity channel control to the light source 180 while delivering transparency control data to the controller 200, maintaining synchronization between illumination and regional transmissivity.

[0401] The image may be a frame from a video stream, and the one or more processors 600 may be configured to repeat configuring the transparency of the at least one panel region for successive frames of the video stream. Optionally, a frame rate of the video stream may be at least 20 frames per second. The processors 600 may stream control data per frame to the controller 200 and coordinate light-source updates so that transparency changes occur coherently at the desired frame rate.

[0402] The multi-region selective-opacity panel 100 may include a Polymer-Dispersed Liquid Crystal (PDLC) panel and the controller 200 may drive the multi-region selective-opacity panel 100 according to the method of the first aspect. In this configuration, the controller 200 may implement AC drive consistent with the charging / draining and modulation teachings hereinabove while applying panel-region transparency values computed by the processors 600.

[0403] The system 7000 may be configured to provide a view using a multi-region selective-opacity panel 100. The system 7000 may include a multi-region selective-opacity panel 100, one or more processors 600, and a controller 200, the multi-region selective-opacity panel 100 including a plurality ofpanel regions 110. The one or more processors 600 may obtain a position of interest 190 relative to the multi-region selective-opacity panel 100, may render, in a transparency map, a view pattern located relative to the position of interest 190, the view pattern defining a view region having transparency values greater than those of surrounding regions, may map, in accordance with the view pattern, a transparency map region of the transparency map to at least one panel region 110, and may provide control data to the controller 200, the control data including a panel region transparency value for the at least one panel region in accordance with a transparency value of the transparency map region. The controller 200 may provide an AC drive signal to the at least one panel region in accordance with the panel region transparency value, thereby creating a view across the multi-region selective-opacity panel 100. Sensors operatively coupled to the processors 600 may include, without limitation, vision cameras, depth sensors, ultra-wideband anchors / tags, or interfaces to building / vehicle telemetry that furnish the position of interest 190; the processors 600 may buffer, fuse, and time-stamp such inputs and generate the corresponding control data stream to the controller 200.

[0404] The multi-region selective-opacity panel 100 may include a Polymer-Dispersed Liquid Crystal (PDLC) panel. In such arrangements, the controller 200 may implement per-region AC drive while maintaining a substantially zero-mean excitation and applying the panel-region transparency values provided by the processors 600. Reference is now made to the drawings in which Figure 33 is a drawing of an exemplary system 7000 for providing a view using a multi-region selective-opacity panel used to provide visibility between an observer and an observee, in accordance with the teachings of the present invention.

[0405] The one or more processors 600 may update the transparency map when the position of interest 190 moves. The update cadence may be selected in view of panel response and sensing latency, with optional double-buffering so that the controller 200 applies coherent changes across affected panel regions 110. The view pattern may have a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person shaped pattern, with per-shape parameters (e.g., radius, width, height) stored in memory and adjustable by policy.

[0406] The position of interest 190 may include a distance relative to the multi-region selective- opacity panel 100, and the one or more processors 600 may adjust at least one panel region 110 from an at least partially scattering configuration to an at least partially transmissive configuration when the distance of the position of interest 190 is within a distance threshold. Optionally, a size of the view region may be a monotonically decreasing function of the distance of the position of interest 190, and transparency within the view region may be a monotonically decreasing function of the distance of the position of interest 190. The processors 600 may implement these relationships by applying calibrated look-up tables to derive target size and transparency, and then emitting control data accordingly.

[0407] The position of interest 190 may further include an elevation and the one or more processors 600 may locate the view pattern relative to the elevation. Elevation may be obtained from a 3D pose estimate, floor-plane estimation, or external telemetry and expressed in a panel-relative coordinate frame maintained in processor memory for registration.

[0408] The position of interest 190 may be a position of an observer and the view may allow the observer to see through the multi-region selective-opacity panel 100. The one or more processors 600 may obtain a sight direction of the observer and may locate the view pattern relative to an intersection of the sight direction with the multi-region selective-opacity panel 100. Sensing for sight direction may include camera-based gaze or head-pose estimation or wearable tracker input, with the processors 600 applying a calibrated transform to compute the intersection and generating corresponding control data for the controller 200.

[0409] The position of interest 190 may be a position of a light source and the view may allow the light source to illuminate through the multi-region selective-opacity panel 100. The processors 600 may accept light-source pose via device telemetry or sensing, place the view pattern relative to the light-path intersection, and provide control data so that the controller 200 configures a transmissive aperture along that path. Where applicable, a light source 180 under processor control may be synchronized to transparency updates as described hereinabove for image / intensity embodiments.

[0410] The position of interest 190 may be a first position of interest 190 located on a first side of the multi-region selective-opacity panel 100, and the one or more processors 600 may obtain a second position of interest 192 on a second side of the multi-region selective-opacity panel 100. A line of sight 195 may be computed from the first position of interest 190 to the second position of interest 192, the line of sight 195 comprising an intersection at the multi-region selective-opacity panel 100, and the view pattern may be located relative to the intersection of the line of sight 195 at the multi-region selective-opacity panel 100. Optionally, the view pattern may be updated when the second position of interest 192 moves. The processors 600 may maintain registration between sensing coordinate frames on both sides and the panel frame so that intersections are computed consistently and view placement remains aligned, with the controller 200 applying the resulting control data.

[0411] The first position of interest 190 may include a first distance relative to the multi-region selective-opacity panel 100 and the second position of interest 192 may include a second distance relative to the multi-region selective-opacity panel 100. At least one panel region 110 may be adjusted from an at least partially scattering configuration to an at least partially transmissive configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold. The processors 600 may evaluate both thresholds with hysteresis and, upon satisfaction, emit control datato form or resize the view pattern; otherwise, previously affected panel regions 110 may be returned toward lower transparency.

[0412] The system 7000 may further include a light source 180 located on a first side of the multiregion selective-opacity panel 100 and configured to project light. The position of interest 190 may be the light source and the view may be used to project an image onto a surface located on a second side of the multi-region selective-opacity panel 100. The processors 600 may maintain light-source pose and the target surface geometry, locate the view pattern at the beam intersection, and coordinate timing with the controller 200 so that the transmissive aperture remains registered to the projected content.

[0413] The system 7000 may further include a second multi-region selective-opacity panel 100'. The multi-region selective-opacity panel 100 may be a first multi-region selective-opacity panel 100 and a first view may be configured thereon. A second view may be configured by adjusting a transparency of at least one panel region of the second multi-region selective-opacity panel 100', thereby allowing an at least partial visibility from the position of interest 190 across the first multi-region selective-opacity panel 100 and the second multi-region selective-opacity panel 100'. The processors 600 may apply a stored registration between the first and second panel frames and emit coordinated control data to the controller(s) driving each panel.

[0414] A second position of interest 192 may be obtained on an opposite side of the second multiregion selective-opacity panel 100'. A line of sight 195 may be computed from the first position of interest 190 towards the second position of interest 192, the line of sight 195 comprising a first intersection at the first multi-region selective-opacity panel 100 and a second intersection at the second multi-region selective-opacity panel 100'. A first view region may be located relative to the first intersection and a second view region may be located relative to the second intersection, thereby allowing at least partial visibility between the first position of interest 190 and the second position of interest 192 across the first view region and the second view region. The processors 600 may keep both views co-registered as either position of interest 190 moves by updating control data to each controller 200 accordingly.

[0415] The first position of interest 190 may be an observer and the second position of interest 192 may be an observee, and the at least partial visibility across the first view region and the second view region may allow the observer to see the observee. Figure 33 illustrates such an arrangement, with processors 600 localizing the observer and observee, computing line-of-sight intersections with the relevant panels, and the controller(s) 200 providing AC drive to the corresponding panel regions 110 to form the view regions.

[0416] The multi-region selective-opacity panel 100 may include a PDLC panel and the controller 200 may drive the multi-region selective-opacity panel 100 according to the method of the first aspect. Theprocessors 600 may continue to supply control data comprising panel-region transparency values, while the controller 200 applies AC drive consistent with the charging, draining, and modulation teachings described hereinabove.

[0417] The system 7000 may be configured to create an obstruction using a multi-region selective- opacity panel 100. The system 7000 may include a multi-region selective-opacity panel 100, one or more processors 600, and a controller 200, the multi-region selective-opacity panel 100 including a plurality of panel regions 110. The one or more processors 600 may obtain a position of interest 190 relative to the multi-region selective-opacity panel 100, may render, in a transparency map, an obstruction pattern located relative to the position of interest 190, the obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions, may map, in accordance with the obstruction pattern, a transparency map region of the transparency map to at least one panel region 110, and may provide control data to the controller 200, the control data including a panel region transparency value for the at least one panel region in accordance with a transparency value of the transparency map region. The controller 200 may provide an AC drive signal to the at least one panel region in accordance with the panel region transparency value, thereby creating an obstruction across the multi-region selective-opacity panel 100. Sensors coupled to the processors 600 may furnish the position of interest 190 (e.g., cameras, depth sensors, UWB anchors / tags, or device telemetry), and the processors 600 may buffer and fuse such inputs before emitting control data to the controller 200.

[0418] The multi-region selective-opacity panel 100 may include a Polymer-Dispersed Liquid Crystal (PDLC) panel. The controller 200 may thus maintain a substantially zero-mean AC drive while applying panel-region transparency values that lower transmission within the obstruction region relative to surrounding regions.

[0419] The obstruction pattern may be updated when the position of interest 190 moves. The processors 600 may maintain a panel-relative registration and update cadence coordinated with panel response, while the controller 200 applies coherent changes to the affected panel regions 110.

[0420] The obstruction pattern may have a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and / or a person shaped pattern. Shape parameters (e.g., radius, width, height, feathering) may be stored in memory and adjusted by policy to meet privacy or glare-control objectives.

[0421] The position of interest 190 may include a distance relative to the multi-region selective- opacity panel 100, and at least one panel region 110 may be adjusted from an at least partially transmissive configuration to an at least partially scattering configuration when the distance of the position of interest 190 is within a distance threshold. Optionally, a size of the obstruction region may be a monotonically decreasing function of the distance of the position of interest 190. Optionally, an opacity within theobstruction region may be a monotonically decreasing function of the distance of the position of interest 190. The processors 600 may implement these relationships by evaluating thresholds with hysteresis and by applying calibrated look-up tables so that target size and opacity are derived consistently from distance.

[0422] The position of interest 190 may further include an elevation and the obstruction pattern may be located relative to the elevation. Elevation may be computed from 3D pose, floor-plane estimation, or external telemetry and expressed in a panel-relative coordinate frame maintained in processor memory.

[0423] The position of interest 190 may be a position of an observer and the obstruction may prevent the observer from seeing, at least partially, through the multi-region selective-opacity panel 100. The one or more processors 600 may reduce transmission within an obstruction region aligned to the observer's likely sight path while leaving surrounding regions at higher transmission for ambient light.

[0424] A sight direction of the observer may be obtained and the obstruction pattern may be located relative to an intersection of the sight direction with the multi-region selective-opacity panel 100. Gaze / head-pose sensing or wearable tracker input may be transformed by the processors 600 into a panel intersection for placement of the obstruction region, and corresponding control data may be issued to the controller 200.

[0425] The position of interest 190 may be a position of a light source and the obstruction may prevent the light source from illuminating, at least partially, through the multi-region selective-opacity panel 100. The processors 600 may accept light-source pose (sensed or by device telemetry), place the obstruction region at the beam intersection, and command reduced transmission to attenuate flux along the path.

[0426] The position of interest 190 may be a first position of interest 190 located on a first side of the multi-region selective-opacity panel 100, a second position of interest 192 may be obtained on a second side of the multi-region selective-opacity panel 100, and a line of sight 195 may be computed from the first position of interest 190 to the second position of interest 192, the line of sight 195 comprising an intersection at the multi-region selective-opacity panel 100. The obstruction pattern may be located relative to the intersection of the line of sight 195 at the multi-region selective-opacity panel 100. Optionally, the obstruction pattern may be updated when the second position of interest 192 moves. The processors 600 may maintain cross-side registration and update the obstruction placement as either position changes, while the controller 200 applies the resulting control data.

[0427] The first position of interest 190 may include a first distance relative to the multi-region selective-opacity panel 100 and the second position of interest 192 may include a second distance relative to the multi-region selective-opacity panel 100, and at least one panel region 110 may be adjusted from an at least partially transmissive configuration to an at least partially scattering configuration when the firstdistance is within a first distance threshold and the second distance is within a second distance threshold. The processors 600 may evaluate both thresholds with hysteresis to form or remove the obstruction accordingly.

[0428] The position of interest 190 may be a light source located on a first side of the multi-region selective-opacity panel 100, and the obstruction region may be used to project a shadow onto a surface located on a second side of the multi-region selective-opacity panel 100. As depicted in Figure 34, the processors 600 place the obstruction region at the beam intersection to cast a shadow on the target surface, and the controller 200 drives the corresponding panel regions 110 to lower transmission.

[0429] The system 7000 may further include a second multi-region selective-opacity panel 100'. The multi-region selective-opacity panel 100 may be a first multi-region selective-opacity panel 100 and a first obstruction may be configured thereon. A second obstruction pattern may be rendered by adjusting a transparency of at least one panel region of the second multi-region selective-opacity panel 100', thereby preventing complete visibility from the position of interest 190 across the first multi-region selective-opacity panel 100 and the second multi-region selective-opacity panel 100'. The processors 600 may apply a stored registration between panel frames to coordinate obstruction placement on both panels.

[0430] The position of interest 190 may be a first position of interest 190 and a second position of interest 192 may be obtained on an opposite side of the second multi-region selective-opacity panel 100'. A line of sight 195 from the first position of interest 190 towards the second position of interest 192 may be computed, the line of sight 195 comprising a first intersection at the first multi-region selective-opacity panel 100 and a second intersection at the second multi-region selective-opacity panel 100'. A first obstruction region may be located relative to the first intersection and a second obstruction region may be located relative to the second intersection, thereby preventing complete visibility between the first position of interest 190 and the second position of interest 192 across the first obstruction region and the second obstruction region. The processors 600 may keep both obstructions co-registered as either position changes.

[0431] The first position of interest 190 may be an observer and the second position of interest 192 may be an observee, and preventing complete visibility across the first obstruction region and the second obstruction region may prevent the observer from seeing the observee. The processors 600 may continue to emit control data that maintains reduced transmission along the relevant sight path while the controller(s) 200 supply the corresponding AC drive to the addressed panel regions 110.

[0432] The multi-region selective-opacity panel 100 may include a PDLC panel and the controller 200 may drive the multi-region selective-opacity panel 100 according to the method of the first aspect. The processors 600 may persist in supplying control data that lowers transparency within obstruction regionsrelative to surrounding regions, while the controller 200 applies AC drive consistent with the charging, draining, and modulation teachings described hereinabove.

[0433] The invention described herein is not to be limited to the particular embodiments described hereinabove, as variations of these embodiments may be made and still fall within the scope of the appended claims. It is also to be understood that the terminology employed is for the purpose of describing particular embodiments; and is not intended to be limiting. Instead, the scope of the present invention will be established by the appended claims.

[0434] In order to provide a clear and consistent understanding of the terms used in the present specification, a number of definitions are provided below. Moreover, unless defined otherwise, all technical and scientific terms as used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this disclosure pertains.

[0435] Use of the word "a” or "an” when used in conjunction with the term "comprising” in the claims and / or the specification may mean "one”, but it is also consistent with the meaning of "one or more”, "at least one”, and "one or more than one”. Similarly, the word "another” may mean at least a second or more.

[0436] As used in this specification and claim(s), the expression "at least one of followed by a set of elements suggests that any combination of the elements from the set is being considered, including a single element from the set, and all elements from the set. For clarity, "at least one of followed by a set does not strictly refer to having at least the whole set once, and possibly multiple times.

[0437] As used in this specification and claim(s), the words "comprising” (and any form of comprising, such as "comprise” and "comprises”), "having” (and any form of having, such as "have” and "has”), "including” (and any form of including, such as "include” and "includes”) or "containing” (and any form of containing, such as "contain” and "contains”), are inclusive or open-ended and do not exclude additional, unrecited elements or process steps.

[0438] Unless otherwise indicated, numeric ranges include their endpoints and all sub-ranges and individual values encompassed therein. As used herein, the term "about” when modifying a quantity or value denotes ±10% of the stated value or an amount appropriate to the context (e.g., manufacturing tolerance or measurement uncertainty), unless otherwise specified. Unless the context clearly indicates otherwise, the term "or” is used in the inclusive sense (and / or). The phrase "configured to” describes structure, hardware, or programmed logic that is arranged, adapted, or operable to perform the recited function and is not limited to capability by mere intended use. Unless a particular order is explicitly required, steps of a method may be performed in any suitable order, and steps may be added, omitted, or performed concurrently without departing from the scope of the claims. Features described in connection with one embodiment may be used in combination with features of another embodiment unless such combinationis technically incompatible. Reference numerals in the claims or description are for convenience only and shall not be construed as limiting the scope of the claims.

[0439] As will be understood by a skilled person, other variations and combinations may be made to the various embodiments of the invention as described herein above. The scope of the claims should not be limited by the preferred embodiments set forth; but should be given the broadest interpretation consistent with the description as a whole.

[0440] A method is generally conceived to be a self-consistent sequence of steps leading to a desired result. These steps require physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic / electromagnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It is convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, parameters, items, elements, objects, symbols, characters, terms, numbers, or the like. It should be noted, however, that all of these terms and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. The description of the present invention has been presented for purposes of illustration but is not intended to be exhaustive or limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments were chosen to explain the principles of the invention and its practical applications and to enable others of ordinary skill in the art to understand the invention in order to implement various embodiments with various modifications as might be suited to other contemplated uses.

[0441] A system may generally be conceived as an arrangement of multiple components that work together to achieve a particular function or result. These components each may have distinct roles and contribute to the overall operation of the system. It is convenient to describe these components as units, modules, parts, or elements. Components may be physical or logical in nature. In practice, systems may be implemented in various forms. While systems are typically comprised of multiple distinct components, in some embodiments, all or some components may coexist within a single device. This integration does not alter the fundamental understanding of the operation but rather represents an embodiment where functionality is consolidated. Such a configuration may be advantageous for specific applications where space, efficiency, or other considerations are paramount. Regardless of configuration, systems are understood to operate through physical interactions, which may, in some embodiments, be achieved through electronic components such as RAM, buses and processors.

Claims

1. CLAIMSWhat is claimed is:1 . A method (1000) for driving a Polymer-Dispersed Liquid Crystal (PDLC) panel (100), comprising:- at a PDLC region (110) of the PDLC panel (100):- grounding (1110) a back side of the PDLC region (110) to a ground connection (122);- applying (1120) a voltage to a front side of the PDLC region (110) via a first gate, thereby causing the PDLC region (110) to accumulate a charge and transition into a first transparency state; and- draining (1130) the charge from the front side of the PDLC region (110) via a second gate subsequent to interrupting the voltage via the first gate, thereby causing the PDLC region (110) to transition into a second transparency state; wherein one of the first transparency state and the second transparency state is an at least partially transmissive state and the other is an at least partially scattering state.

2. The method (1000) of claim 1 , wherein the PDLC region (110) transitions into the second transparency state within 50 ms after closing the second gate.

3. The method (1000) of claim 1 or claim 2, wherein the first gate and the second gate form a half-bridge between a supply rail and the ground connection (122), the half-bridge having a switching node electrically coupled to the front side of the PDLC region (110).

4. The method (1000) of any one of claims 1 to 3, wherein the voltage applied to the front side comprises an alternating current (AC) signal.

5. The method (1000) of any one of claims 1 to 4, wherein the PDLC panel (100) is a multi-region PDLC panel, the method (1000) further comprising:- grounding (1210) the back side of each of two or more adjacent PDLC regions (110) to the ground connection (122); generating (1220) two or more phase-shifted alternating current (AC) signals having a common frequency; and- respectively distributing (1230) the two or more phase-shifted AC signals to respective front sides of the two or more adjacent PDLC regions (110) of the multi-region PDLC panel (100).

6. The method (1000) of claim 5, wherein the common frequency is between 60 Hz and 120 Hz.

7. The method (1000) of claim 5 or claim 6, wherein the two or more phase-shifted AC signals are uniformly phase-spaced from one another.

8. The method (1000) of any one of claims 5 to 7, wherein generating (1220) the two or more phase- shifted AC signals comprises:- alternating (1225) between a positive Direct Current (DC) supply and a negative DC supply, thereby balancing a load of the two or more phase-shifted AC signals across the positive DC supply and the negative DC supply.

9. The method (1000) of claim 8, wherein the positive DC supply is less than 57 volts and the negative DC supply is greater than -57 volts.

10. The method (1000) of any one of claims 4 to 9, further comprising:- obtaining (1310) an opacity response curve of the PDLC region (110);- providing (1330) an alternating current (AC) signal to a front side of the PDLC region (110); and- modulating (1340) the AC signal according to the opacity response curve.11 . The method (1000) of claim 10, wherein modulating (1340) the AC signal comprises:- interrupting (1342) the AC signal according to a Pulse-Width Modulation (PWM) signal, thereby generating a PWM-modulated AC signal.

12. The method (1000) of claim 11 , wherein modulating (1340) the AC signal further comprises:- filtering (1344) the PWM-modulated AC signal with a low-pass filter.

13. The method (1000) of any one of claims 4 to 12, wherein the PDLC panel (100) is a multi-region PDLC panel, the method (1000) further comprising:- assigning (1410) a region identifier to a region of the multi-region PDLC panel (100);receiving (1420) a configuration stream comprising the region identifier and a region configuration; and modulating (1430) an alternating current (AC) signal according to the region configuration via a region controller configured to drive the region corresponding to the region identifier.

14. The method (1000) of claim 13, wherein the configuration stream is a Digital Multiplex (DMX) data stream.

15. The method (1000) of any one of claims 1 to 14, wherein, prior to driving, the PDLC panel (100) has been manufactured by a process comprising:- isolating (1510) a plurality of PDLC regions (110) within a transparent conductive coating of the PDLC panel (100); and- connecting (1520) at least one PDLC region of the plurality of PDLC regions (110) to a region controller configured to drive the at least one PDLC region (110).

16. The method (1000) of claim 15, wherein isolating (1510) the PDLC regions (110) comprises:- providing (1512) a substrate carrying a transparent conductive coating; and- patterning (1514) the transparent conductive coating to form isolation channels in the transparent conductive coating.

17. The method (1000) of claim 16, wherein patterning (1514) comprises:- ablating (1516) the transparent conductive coating using a laser prior to lamination to a PDLC layer.

18. The method (1000) of claim 16 or claim 17, wherein isolating (1510) the PDLC regions (110) further comprises:- laminating (1518) the patterned substrate to a PDLC layer, thereby defining the plurality of PDLC regions (110).

19. The method (1000) of any one of claims 15 to 18, wherein the transparent conductive coating comprises indium tin oxide (ITO) deposited on a polymeric substrate.

20. The method (1000) of claim 19, wherein the isolation channels have a width less than 100 m and the ITO sheet resistance is between 10 Q / sq and 200 Q / sq.21 . The method (1000) of any one of claims 15 to 20, wherein, prior to driving, the PDLC panel (100) has been manufactured by a process further comprising:- providing (1530) a second substrate carrying a transparent conductive coating;- patterning (1532) the transparent conductive coating of the second substrate to form conductive traces routed from a perimeter of the PDLC panel (100) toward interior locations;- laminating (1534) the second substrate and a PDLC layer with a dielectric interlayer therebetween; and- forming (1536) conductive interconnects between the conductive traces and input conductive coatings of selected PDLC regions (110).

22. The method (1000) of any one of claims 15 to 21 , wherein connecting (1520) the at least one PDLC region (110) comprises using a flexible Printed Circuit Board (PCB).

23. The method (1000) of claim 22, wherein the flexible PCB and the region controller are embedded within a perimeter frame of the PDLC panel (100).

24. The method (1000) of claim 22 or claim 23, wherein connecting (1520) comprises bonding the flexible PCB to contact pads using an anisotropic conductive film (ACF).

25. A method (2000) for retrofitting a glazing (20) with a multi-region Polymer-Dispersed Liquid Crystal (PDLC) panel overlay, the method (2000) comprising:- attaching (2010) a PDLC panel overlay (100) to an exposed surface of the glazing (20), the PDLC panel overlay (100) comprising a plurality of PDLC regions (110), an interconnect bus (160) along at least one edge of the PDLC panel overlay (100), and electrical coupling between the interconnect bus (160) and an input conductive coating of the plurality of PDLC regions (110);- connecting (2020) the interconnect bus (160) to an edge control module (300);- supplying (2030) alternating current (AC) power and a data signal to the edge control module (300) from an external control module (350); andadjusting (2040) the data signal to drive the plurality of PDLC regions (110) via the edge control module (300).

26. The method (2000) of claim 25, wherein attaching (2010) the PDLC panel overlay comprises at least one of:- applying (2012) an optically clear adhesive; and- installing (2014) a secondary frame retained within a window reveal of the glazing (20).

27. The method (2000) of claim 25 or claim 26, wherein the edge control module is mounted within a perimeter frame of the glazing (20).

28. The method (2000) of any one of claims 25 to 27, wherein the PDLC panel overlay (100) is a first PDLC panel overlay and the edge control module is a first edge control module, the method further comprising:- connecting (2050) the first edge control module to a second edge control module, the second edge control module configured to drive a second PDLC panel overlay; and- adjusting (2060) the data signal to drive the second PDLC panel overlay via the first edge control module and the second edge control module.

29. The method (2000) of any one of claims 25 to 28, wherein the plurality of PDLC regions are driven according to any one of claims 1 to 24.

30. A method (3000) for displaying a transparency map using a multi-region selective-opacity panel (100), comprising:- mapping (3010) a transparency map region of the transparency map to at least one panel region from a plurality of panel regions (110) of the multi-region selective-opacity panel (100);- configuring (3020) a transparency of the at least one panel region (110) in accordance with a transparency value of the transparency map region.31 . The method (3000) of claim 30, wherein the transparency map is an image comprising at least one of a luminance channel, a grayscale channel, an opacity channel, and a transparency channel and the transparency map region is an image region.

32. The method (3000) of claim 31 , wherein the plurality of panel regions (110) is configured as a regular grid, the image is a raster image, the image region is a pixel of the raster image, and mapping the image region comprises mapping the pixel to the regular grid.

33. The method (3000) of claim 31 or claim 32, further comprising:- processing (3030) the image to obtain one or more intensity channels and the transparency channel;- configuring (3040) the transparency of the at least one panel region in accordance with the transparency channel; and- projecting (3050) light onto the multi-region selective-opacity panel (100) in accordance with the one or more intensity channels.

34. The method (3000) of claim 33, wherein the one or more intensity channels comprise at least one of a color channel, a luminance channel, and a chrominance channel.

35. The method (3000) of any one of claims 31 to 34, wherein the image is a frame from a video stream, the method further comprising:- repeating the configuring (3020) of the transparency for successive frames of the video stream.

36. The method (3000) of claim 35, wherein a frame rate of the video stream is at least 20 frames per second.

37. The method (3000) of claim 30, further comprising:- obtaining (3110) a position of interest (190) relative to the multi-region selective-opacity panel (100); and- rendering (3115), in the transparency map, a view pattern located relative to the position of interest (190), the view pattern defining a view region having transparency values greater than those of surrounding regions; and wherein configuring (3020) the transparency of at least one panel region (110) corresponding to the view pattern creates a view across the multi-region selective-opacity panel (100).

38. The method (3000) of claim 37, further comprising:updating (3120) the transparency map when the position of interest (190) moves.

39. The method (3000) of claim 37 or claim 38, wherein the view region is any one of a circular region, a vertical region, a horizontal region, and a person-shaped region.

40. The method (3000) of any one of claims 37 to 39, wherein the position of interest (190) comprises a distance relative to the multi-region selective-opacity panel (100) and wherein configuring (3020) comprises adjusting at least one panel region of the multi-region selective-opacity panel (100) from an at least partially scattering configuration to an at least partially transmissive configuration when the distance of the position of interest (190) is within a distance threshold.41 . The method (3000) of any one of claims 37 to 40, wherein a size of the view region is a monotonically decreasing function of the distance of the position of interest (190).

42. The method (3000) of any one of claims 37 to 41 , wherein transparency values within the view region are a monotonically decreasing function of the distance of the position of interest (190).

43. The method (3000) of any one of claims 37 to 42, wherein the position of interest (190) further comprises an elevation and wherein the view pattern is located relative to the elevation.

44. The method (3000) of any one of claims 37 to 43, wherein the position of interest (190) is a position of an observer and wherein the view region allows the observer to see through the multi-region selective-opacity panel (100).

45. The method (3000) of claim 44, further comprising:- obtaining (3130) a sight direction of the observer; and- locating (3135) the view pattern relative to an intersection of the sight direction with the multi-region selective-opacity panel (100).

46. The method (3000) of any one of claims 37 to 45, wherein the position of interest (190) is a position of a light source and wherein the view region allows the light source to illuminate through the multi-region selective-opacity panel (100).

47. The method (3000) of any one of claims 37 to 46, wherein the position of interest (190) is a first position of interest located on a first side of the multi-region selective-opacity panel (100), the method (3000) further comprising:- obtaining (3140) a second position of interest (192) on a second side of the multi-region selective-opacity panel (100); and- computing (3145) a line of sight (195) going from the first position of interest to the second position of interest (192), comprising an intersection at the multi-region selective-opacity panel (100); wherein the view pattern is located relative to the intersection of the line of sight (195) at the multi-region selective-opacity panel (100).

48. The method (3000) of claim 47, further comprising:- updating (3150) the view pattern when the second position of interest (192) moves.

49. The method (3000) of claim 47 or claim 48, wherein the first position of interest comprises a first distance relative to the multi-region selective-opacity panel (100) and the second position of interest (192) comprises a second distance relative to the multi-region selective-opacity panel (100), and wherein configuring (3020) comprises:- adjusting (3155) at least one panel region of the multi-region selective-opacity panel (100) from an at least partially scattering configuration to an at least partially transmissive configuration when the first distance of the first position of interest is within a first distance threshold and the second distance of the second position of interest (192) is within a second distance threshold.

50. The method (3000) of any one of claims 37 to 49, wherein the position of interest (190) is a light source located on a first side of the multi-region selective-opacity panel (100), and the view region is configured to allow light from the light source to pass through the panel and project an image onto a surface located on a second side of the panel.51 . The method (3000) of any one of claims 37 to 50, wherein the multi-region selective-opacity panel (100) is a first multi-region selective-opacity panel (100) and the view pattern is a first view pattern, the method (3000) further comprising:- rendering (3160) a second view pattern by adjusting a transparency of at least one region of a second multi-region selective-opacity panel (100'), thereby allowing an at least partial visibility from the position of interest (190) across the first multi-region selective-opacity panel (100) and the second multi-region selective-opacity panel (100').

52. The method (3000) of claim 51 , wherein the position of interest (190) is a first position of interest, the method further comprising:- obtaining (3170) a second position of interest (192) on an opposite side of the second multi-region selective-opacity panel (100');- computing (3175) a line of sight (195) going from the first position of interest towards the second position of interest (192), comprising a first intersection at the first multi-region selective-opacity panel (100) and a second intersection on the second multi-region selective-opacity panel (100'); and wherein a first view region is located relative to the first intersection of the line of sight (195) at the first multi-region selective-opacity panel (100) and a second view region is located relative to the second intersection of the second multi-region selective-opacity panel (100'), thereby allowing the at least partial visibility between the first position of interest and the second position of interest (192) across the first view region and the second view region.

53. The method (3000) of claim 51 or claim 52, wherein the first position of interest is an observer, and the second position of interest (192) is an observee, and wherein the at least partial visibility across the first view region and the second view region allows the observer to see the observee.

54. The method (3000) of claim 30, further comprising:- obtaining (3210) a position of interest (190) relative to the multi-region selective-opacity panel (100); and- rendering (3220), in the transparency map, an obstruction pattern located relative to the position of interest (190), the obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions; and wherein configuring (3020) the transparency of at least one panel region (110) corresponding to the obstruction pattern creates an obstruction across the multi-region selective-opacity panel (100).

55. The method (3000) of claim 54, further comprising:- updating (3230) the obstruction pattern when the position of interest (190) moves.

56. The method (3000) of any one of claims 54 to 55, wherein the obstruction region is any one of a circular region, a vertical region, a horizontal region, and a person-shaped region.

57. The method (3000) of any one of claims 54 to 56, wherein the position of interest (190) comprises a distance relative to the multi-region selective-opacity panel (100) and wherein configuring (3020) comprises adjusting at least one panel region of the multi-region selective-opacity panel (100) from an at least partially transmissive configuration to an at least partially scattering configuration when the distance of the position of interest (190) is within a distance threshold.

58. The method (3000) of claim 57, wherein a size of the obstruction region is a monotonically decreasing function of the distance of the position of interest (190).

59. The method (3000) of claim 57 or claim 58, wherein an opacity within the obstruction region is a monotonically decreasing function of the distance of the position of interest (190).

60. The method (3000) of any one of claims 54 to 59, wherein the position of interest (190) further comprises an elevation and wherein the obstruction pattern is located relative to the elevation.61 . The method (3000) of any one of claims 54 to 60, wherein the position of interest (190) is a position of an observer and wherein the obstruction region prevents the observer from seeing, at least partially, through the multi-region selective-opacity panel (100).

62. The method (3000) of claim 61 , further comprising:- obtaining (3240) a sight direction of the observer; and- locating (3245) the obstruction pattern relative to an intersection of the sight direction with the multi-region selective-opacity panel (100).

63. The method (3000) of any one of claims 54 to 62, wherein the position of interest (190) is a position of a light source and wherein the obstruction region prevents the light source from illuminating, at least partially, through the multi-region selective-opacity panel (100).

64. The method (3000) of any one of claims 54 to 63, wherein the position of interest (190) is a first position of interest located on a first side of the multi-region selective-opacity panel (100), the method further comprising:- obtaining (3250) a second position of interest (192) on a second side of the multi-region selective-opacity panel (100);- computing (3255) a line of sight (195) going from the first position of interest to the second position of interest (192), comprising an intersection at the multi-region selective-opacity panel (100); and wherein the obstruction pattern is located relative to the intersection of the line of sight (195) at the multi-region selective-opacity panel (100).

65. The method (3000) of claim 64, further comprising:- updating (3260) the obstruction pattern when the second position of interest (192) moves.

66. The method (3000) of claim 64 or claim 65, wherein the first position of interest comprises a first distance relative to the multi-region selective-opacity panel (100) and the second position of interest (192) comprises a second distance relative to the multi-region selective-opacity panel (100), and wherein configuring (3020) comprises adjusting at least one panel region of the multi-region selective-opacity panel (100) from an at least partially transmissive configuration to an at least partially scattering configuration when the first distance of the first position of interest is within a first distance threshold and the second distance of the second position of interest (192) is within a second distance threshold.

67. The method (3000) of any one of claims 54 to 66, wherein the position of interest (190) is a light source located on a first side of the multi-region selective-opacity panel (100), and the obstruction region is used to project a shadow onto a surface located on a second side of the multi-region selective-opacity panel (100).

68. The method (3000) of any one of claims 54 to 67, wherein the multi-region selective-opacity panel (100) is a first multi-region selective-opacity panel (100) and the obstruction pattern is a first obstruction pattern, the method further comprising:- rendering (3270) a second obstruction pattern by adjusting a transparency of at least one region of a second multi-region selective-opacity panel (100'), thereby preventing a complete visibility from the position of interest (190) across the first multi-region selective-opacity panel (100) and the second multi-region selective-opacity panel (100').

69. The method (3000) of claim 68, wherein the position of interest (190) is a first position of interest, the method further comprising:- obtaining (3280) a second position of interest (192) on an opposite side of the second multi-region selective-opacity panel (100'); - computing (3285) a line of sight (195) going from the first position of interest towards the second position of interest (192), comprising a first intersection at the first multi-region selective-opacity panel (100) and a second intersection on the second multi-region selective-opacity panel (100'); wherein a first obstruction region is located relative to the first intersection of the line of sight (195) at the first multi-region selective-opacity panel (100) and a second obstruction region is located relative to the second intersection of the second multi-region selective-opacity panel (100'), thereby preventing the complete visibility between the first position of interest and the second position of interest (192) across the first obstruction region and the second obstruction region.

70. The method (3000) of claim 69, wherein the first position of interest is an observer, and the second position of interest (192) is an observee, and wherein preventing complete visibility across the first obstruction region and the second obstruction region prevents the observer from seeing the observee.71 . The method (3000) of any one of claims 54 to 70, wherein the multi-region selective-opacity panel (100) comprises a PDLC panel driven according to any one of claims 1 to 24.

72. The method (3000) of any one of claims 30 to 71 , wherein the multi-region selective-opacity panel (100) is a Polymer-Dispersed Liquid Crystal (PDLC) panel driven according to any one of claims 1 to 24.

73. A Polymer-Dispersed Liquid Crystal (PDLC) system (5000) comprising:- a power source (120);- a ground connection (122); and- a PDLC panel (100) comprising one or more PDLC regions (110), each PDLC region (110) comprising:- a front side (112) covered with an input conductive coating;- a back side (116) covered with a ground conductive coating;- an input gate (114) configured to selectively connect the input conductive coating to the power source (120); and- a draining gate (118) configured to selectively connect the input conductive coating to the ground connection (122); wherein each PDLC region (110) is configured such that:- with the input gate (114) closed and the draining gate (118) open, the input conductive coating is charged, thereby causing the PDLC region (110) to transition into a first transparency state; and- with the input gate (114) open and the draining gate (118) closed, charge is drained from the input conductive coating, thereby causing the PDLC region (110) to transition into a second transparency state; and wherein one of the first transparency state and the second transparency state is an at least partially transmissive state and the other is an at least partially scattering state.

74. The system (5000) of claim 73, wherein the PDLC region (110) transitions into the second transparency state within 50 ms after the draining gate (118) is closed.

75. The system (5000) of claim 73 or claim 74, wherein the input gate (114) and the draining gate (118) form a half-bridge between a supply rail of the power source (120) and the ground connection (122), a switching node of the half-bridge being electrically coupled to the input conductive coating.

76. The system (5000) of any one of claims 73 to 75, wherein the input conductive coating is driven by an alternating current (AC) signal.

77. The system (5000) of any one of claims 73 to 76 further comprising:- a controller (200) configured to:- generate two or more phase-shifted alternating current (AC) signals having a common frequency; and- distribute the two or more phase-shifted AC signals to respective front sides (112) of at least two adjacent PDLC regions (110) of the PDLC panel (100).

78. The system (5000) of claim 77, wherein the common frequency is between 60 Hz and 120 Hz.

79. The system (5000) of claim 77 or claim 78, wherein the two or more phase-shifted AC signals are uniformly phase-spaced from one another.

80. The system (5000) of any one of claims 77 to 79, wherein the power source (120) further comprises:- a positive Direct Current (DC) supply; and- a negative DC supply; and wherein the controller (200) is configured to generate the two or more phase-shifted AC signals by alternating between the positive DC supply and the negative DC supply, thereby balancing a load of the two or more phase-shifted AC signals across the positive DC supply and the negative DC supply.81 . The system (5000) of claim 80, wherein the positive DC supply is below 57 volts and the negative DC supply is greater than -57 volts.

82. The system (5000) of any one of claims 77 to 81 , further comprising:- a voltage modulator (210) electrically connectable between the controller (200) and the input conductive coating of at least one PDLC region (110), the voltage modulator (210) being configured to modulate an effective voltage of an AC drive signal delivered to the input conductive coating in accordance with an opacity response curve of the at least one PDLC region (110); wherein the controller (200) is configured to provide AC drive signals.

83. The system (5000) of claim 82, wherein the voltage modulator (210) comprises a Pulse-Width Modulation (PWM) module (212) configured to apply PWM gating to the AC drive signal to generate a PWM-modulated AC drive signal.

84. The system (5000) of claim 83, wherein the voltage modulator (210) further comprises a low-pass filter (214) configured to filter the PWM-modulated AC drive signal.

85. The system (5000) of any one of claims 77 to 84, wherein the controller (200) is configured to provide AC drive signals and the PDLC panel (100) comprises a plurality of PDLC regions (110), the system (5000) further comprising:- a plurality of region controllers (220), each region controller (220) being electrically connected to at least one PDLC region (110) of the plurality of PDLC regions (110) and being addressable by a region identifier; and- a communication module (250);wherein:- each region controller (220) is configured to modulate an AC drive signal according to a region configuration to drive the PDLC region (110) corresponding to the region identifier; and- the communication module (250) is configured to receive a configuration stream comprising the region identifier and the region configuration, and to transmit the region configuration to at least one region controller (220) corresponding to the region identifier.

86. The system (5000) of claim 85, wherein the configuration stream is a Digital Multiplex (DMX) data stream.

87. The system (5000) of claim 85 or claim 86, wherein the PDLC regions (110) are electrically isolated from one another within a transparent conductive coating of the PDLC panel (100).

88. The system (5000) of claim 87, wherein the transparent conductive coating is patterned to form isolation channels in the transparent conductive coating.

89. The system (5000) of claim 87 or 88, wherein the transparent conductive coating is laser-ablated to form the isolation channels.

90. The system (5000) of any one of claims 87 to 89, wherein the transparent conductive coating is disposed on a substrate that is laminated to a PDLC layer.91 . The system (5000) of any one of claims 87 to 90, wherein the transparent conductive coating comprises indium tin oxide (ITO) deposited on a polymeric substrate.

92. The system (5000) of claim 91 , wherein the isolation channels have a width less than 100 pm and the ITO has a sheet resistance between 10 Q / sq and 200 Q / sq.

93. The system (5000) of any one of claims 87 to 92, wherein the PDLC panel (100) comprises:- a first transparent conductive layer patterned to define a plurality of PDLC regions (110); and- at least one additional transparent conductive layer patterned to form conductive traces routed from a panel perimeter to interior PDLC regions (110), the additional transparent conductive layer being electrically coupled to the PDLC regions (110) via electrically conductive interconnects at registered contact points.

94. The system (5000) of claim 93, wherein the at least one additional transparent conductive layer is provided on a second substrate laminated to a PDLC layer with a dielectric interlayer therebetween.

95. The system (5000) of any one of claims 87 to 94, further comprising a flexible printed circuit board (PCB) (160) electrically connected to the transparent conductive coating and configured to connect a power source (120) to respective input conductive coatings of the PDLC regions (110) and to connect a ground connection (122) to respective ground conductive coatings.

96. The system (5000) of claim 95, further comprising a frame and a plurality of region controllers (220), wherein the flexible PCB (160) and the plurality of region controllers (220) are embedded within the frame.

97. The system (5000) of claim 95 or claim 96, wherein the flexible PCB (160) is bonded to contact pads using an anisotropic conductive film (ACF).

98. A Polymer-Dispersed Liquid Crystal (PDLC) retrofit system (6000), comprising:- a PDLC panel overlay (100) attachable to an exposed surface of a glazing (20), the PDLC panel overlay (100) comprising:- a plurality of PDLC regions (110);- an interconnect bus (160) along at least one edge of the PDLC panel overlay (100); and- electrical coupling between the interconnect bus (160) and respective input conductive coatings of the plurality of PDLC regions (110);- an edge control module (300) connectable to the interconnect bus (160); and- an external control module (350) configured to supply alternating current (AC) power and a data signal to the edge control module (300); wherein the edge control module (300) is configured to drive the plurality of PDLC regions (110) via the interconnect bus (160) in accordance with the data signal.

99. The system (6000) of claim 98, further comprising at least one of:- an optically clear adhesive; and a secondary frame retained within a window reveal of the glazing (20);wherein the PDLC panel overlay (100) is attachable to the glazing (20) using the at least one of the optically clear adhesive and the secondary frame.

100. The system (6000) of claim 98 or claim 99, wherein the edge control module (300) is mounted within a perimeter frame of the glazing (20).101 . The system (6000) of any one of claims 98 to 100, further comprising:- a second edge control module (300') configured to drive a second PDLC panel overlay (100'); wherein the edge control module (300) is connectable to the second edge control module (300'), and the edge control module (300) and the second edge control module (300') are configured to distribute the data signal such that the second edge control module (300') drives the second PDLC panel overlay (100').

102. A system (7000) for displaying a transparency map using a multi-region selective-opacity panel (100), comprising:- a multi-region selective-opacity panel (100) comprising a plurality of panel regions (110);- one or more processors (600) configured to:- map a transparency map region of a transparency map to at least one panel region from the plurality of panel regions (110); and- compute a panel region transparency value in accordance with a transparency value of the transparency map region; and- a controller (200) configured to:- receive control data from the one or more processors (600), the control data comprising the panel region transparency value for the at least one panel region; and- provide an AC drive signal to the at least one panel region in accordance with the panel region transparency value.

103. The system (7000) of claim 102, wherein the transparency map is an image, the transparency map region is an image region, and the transparency value is derived from at least one of a transparency channel, an opacity channel, a luminance channel, or a grayscale channel of the image.

104. The system (7000) of claim 103, wherein the plurality of panel regions (110) is arranged in a regular grid, the image is a raster image, the image region is a pixel of the raster image, and the one or more processors (600) are configured to map the pixel to the regular grid.

105. The system (7000) of claim 103 or claim 104, further comprising a light source (180), wherein:- the one or more processors (600) are configured to process the image to obtain one or more intensity channels and a transparency channel and to provide control data to the controller (200) to configure the transparency of the at least one panel region in accordance with the transparency channel; and- the light source (180) is configured to project light onto the multi-region selective-opacity panel (100) in accordance with the one or more intensity channels under control of the one or more processors (600).

106. The system (7000) of claim 105, wherein the one or more intensity channels comprise at least one of a color channel, a luminance channel, and a chrominance channel.

107. The system (7000) of any one of claims 103 to 106, wherein the image is a frame from a video stream, and the one or more processors (600) are configured to repeat configuring the transparency of the at least one panel region for successive frames of the video stream.

108. The system (7000) of claim 107, wherein a frame rate of the video stream is at least 20 frames per second.

109. The system (7000) of claim 102, wherein the one or more processors (600) are further configured to:- obtain a position of interest (190) relative to the multi-region selective-opacity panel (100);- render, in a transparency map, a view pattern located relative to the position of interest (190), the view pattern defining a view region having transparency values greater than those of surrounding regions;- map, in accordance with the view pattern, a transparency map region of the transparency map to at least one panel region (110); and- provide control data to the controller (200), the control data comprising a panel region transparency value for the at least one panel region in accordance with a transparency value of the transparency map region, thereby creating a view across the multi-region selective-opacity panel (100).1 10. The system (7000) of claim 109, wherein the one or more processors (600) are further configured to update the transparency map when the position of interest (190) moves.1 1 1 . The system (7000) of claim 109 or claim 110, wherein the view pattern has a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and a person-shaped pattern.1 12. The system (7000) of any one of claims 109 to 111 , wherein the position of interest (190) comprises a distance relative to the multi-region selective-opacity panel (100), and the one or more processors (600) are configured to adjust at least one panel region (110) from an at least partially scattering configuration to an at least partially transmissive configuration when the distance of the position of interest (190) is within a distance threshold.1 13. The system (7000) of any one of claims 109 to 112, wherein a size of a view region defined by the view pattern is a monotonically decreasing function of the distance of the position of interest (190).1 14. The system (7000) of any one of claims 109 to 113, wherein transparency within the view region is a monotonically decreasing function of the distance of the position of interest (190).1 15. The system (7000) of any one of claims 109 to 114, wherein the position of interest (190) further comprises an elevation, and the one or more processors (600) are configured to locate the view pattern relative to the elevation.1 16. The system (7000) of any one of claims 109 to 115, wherein the position of interest (190) is a position of an observer and the view allows the observer to see through the multi-region selective-opacity panel (100).1 17. The system (7000) of claim 116, wherein the one or more processors (600) are further configured to obtain a sight direction of the observer and to locate the view pattern relative to an intersection of the sight direction with the multi-region selective-opacity panel (100).

118. The system (7000) of any one of claims 109 to 117, wherein the position of interest (190) is a position of a light source and the view allows the light source to illuminate through the multi-region selective-opacity panel (100).

119. The system (7000) of any one of claims 109 to 118, wherein the position of interest (190) is a first position of interest located on a first side of the multi-region selective-opacity panel (100), and the one or more processors (600) are further configured to:- obtain a second position of interest (192) on a second side of the multi-region selective-opacity panel (100);- compute a line of sight (195) from the first position of interest to the second position of interest (192), the line of sight (195) comprising an intersection at the multi-region selective-opacity panel (100); and- locate the view pattern relative to the intersection of the line of sight (195) at the multi-region selective-opacity panel (100).

120. The system (7000) of claim 119, wherein the one or more processors (600) are further configured to update the view pattern when the second position of interest (192) moves.121 . The system (7000) of claim 119 or claim 120, wherein:- the first position of interest comprises a first distance relative to the multi-region selective-opacity panel (100);- the second position of interest (192) comprises a second distance relative to the multi-region selective-opacity panel (100); and- the one or more processors (600) are configured to adjust at least one panel region (110) from an at least partially scattering configuration to an at least partially transmissive configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold.

122. The system (7000) of any one of claims 109 to 121 , further comprising a light source (180) located on a first side of the multi-region selective-opacity panel (100) and configured to project light, wherein the position of interest (190) is the light source, and the view is used to project an image onto a surface located on a second side of the multi-region selective-opacity panel (100).

123. The system (7000) of any one of claims 109 to 122, further comprising a second multi-region selective-opacity panel (100'), wherein the multi-region selective-opacity panel (100) is a first multi-region selective-opacity panel (100) and a first view is configured thereon, and the one or more processors (600) are further configured to configure a second view by adjusting a transparency of at least one panel region of the second multi-region selective-opacity panel (100'), thereby allowing an at least partial visibility from the position of interest (190) across the first multi-region selective-opacity panel (100) and the second multi-region selective-opacity panel (100').

124. The system (7000) of claim 123, wherein the position of interest (190) is a first position of interest, and the one or more processors (600) are further configured to:- obtain a second position of interest (192) on an opposite side of the second multi-region selective-opacity panel (100');- compute a line of sight (195) from the first position of interest towards the second position of interest (192), the line of sight (195) comprising a first intersection at the first multi-region selective-opacity panel (100) and a second intersection at the second multi-region selective-opacity panel (100'); and- locate the first view relative to the first intersection and the second view relative to the second intersection, thereby allowing at least partial visibility between the first position of interest and the second position of interest (192) across the first view and the second view.

125. The system (7000) of claim 123 or claim 124, wherein the first position of interest is an observer, and the second position of interest (192) is an observee, and wherein the at least partial visibility across the first view region and the second view region allows the observer to see the observee.

126. The system (7000) of claim 102, wherein the one or more processors (600) are further configured to:- obtain a position of interest (190) relative to the multi-region selective-opacity panel (100);- render, in a transparency map, an obstruction pattern located relative to the position of interest (190), the obstruction pattern defining an obstruction region having transparency values lower than those of surrounding regions;- map, in accordance with the obstruction pattern, a transparency map region of the transparency map to at least one panel region (110); and- provide control data to the controller (200), the control data comprising a panel region transparency value for the at least one panel region in accordance with a transparency value of the transparency map region, thereby creating an obstruction across the multiregion selective-opacity panel (100).

127. The system (7000) of claim 126, wherein the one or more processors (600) are further configured to update the obstruction pattern when the position of interest (190) moves.

128. The system (7000) of claim 126 or claim 127, wherein the obstruction pattern has a shape selected from a circular pattern, a vertical pattern, a horizontal pattern, and a person shaped pattern.

129. The system (7000) of any one of claims 126 to 128, wherein the position of interest (190) comprises a distance relative to the multi-region selective-opacity panel (100), and the one or more processors (600) are configured to adjust at least one panel region (110) from an at least partially transmissive configuration to an at least partially scattering configuration when the distance of the position of interest (190) is within a distance threshold.

130. The system (7000) of claim 129, wherein a size of an obstruction region defined by the obstruction pattern is a monotonically decreasing function of the distance of the position of interest (190).131 . The system (7000) of claim 129 or claim 130, wherein an opacity within the obstruction region is a monotonically decreasing function of the distance of the position of interest (190).

132. The system (7000) of any one of claims 126 to 131 , wherein the position of interest (190) further comprises an elevation and the one or more processors (600) are configured to locate the obstruction pattern relative to the elevation.

133. The system (7000) of any one of claims 126 to 132, wherein the position of interest (190) is a position of an observer and the obstruction prevents the observer from seeing, at least partially, through the multi-region selective-opacity panel (100).

134. The system (7000) of claim 133, wherein the one or more processors (600) are further configured to obtain a sight direction of the observer and to locate the obstruction pattern relative to an intersection of the sight direction with the multi-region selective-opacity panel (100).

135. The system (7000) of any one of claims 126 to 134, wherein the position of interest (190) is a position of a light source and the obstruction prevents the light source from illuminating, at least partially, through the multi-region selective-opacity panel (100).

136. The system (7000) of any one of claims 126 to 135, wherein the position of interest (190) is a first position of interest located on a first side of the multi-region selective-opacity panel (100), and the one or more processors (600) are further configured to:- obtain a second position of interest (192) on a second side of the multi-region selective- opacity panel (100);- compute a line of sight (195) from the first position of interest to the second position of interest (192), the line of sight (195) comprising an intersection at the multi-region selective-opacity panel (100); and- locate the obstruction pattern relative to the intersection of the line of sight (195) at the multi-region selective-opacity panel (100).

137. The system (7000) of claim 136, wherein the one or more processors (600) are further configured to update the obstruction pattern when the second position of interest (192) moves.

138. The system (7000) of claim 136 or claim 137, wherein the first position of interest comprises a first distance relative to the multi-region selective-opacity panel (100) and the second position of interest (192) comprises a second distance relative to the multi-region selective-opacity panel (100), and the one or more processors (600) are configured to adjust at least one panel region (110) from an at least partially transmissive configuration to an at least partially scattering configuration when the first distance is within a first distance threshold and the second distance is within a second distance threshold.

139. The system (7000) of any one of claims 126 to 138, further comprising a light source (180), wherein the position of interest (190) is the light source located on a first side of the multi-region selective- opacity panel (100), and the obstruction is used to project a shadow onto a surface located on a second side of the multi-region selective-opacity panel (100).

140. The system (7000) of any one of claims 126 to 139, further comprising a second multi-region selective-opacity panel (100'), wherein the multi-region selective-opacity panel (100) is a first multiregion selective-opacity panel (100) and a first obstruction is configured thereon, and the one or more processors (600) are further configured to configure a second obstruction by adjusting asecond opacity of at least one panel region of the second multi-region selective-opacity panel (100'), thereby preventing complete visibility from the position of interest (190) across the first multi-region selective-opacity panel (100) and the second multi-region selective-opacity panel (100').141 . The system (7000) of claim 140, wherein the position of interest (190) is a first position of interest, and the one or more processors (600) are further configured to:- obtain a second position of interest (192) on an opposite side of the second multi-region selective-opacity panel (100');- compute a line of sight (195) from the first position of interest towards the second position of interest (192), the line of sight (195) comprising a first intersection at the first multiregion selective-opacity panel (100) and a second intersection at the second multi-region selective-opacity panel (100'); and- locate the first obstruction relative to the first intersection and the second obstruction relative to the second intersection, thereby preventing complete visibility between the first position of interest and the second position of interest (192) across the first obstruction and the second obstruction.

142. The system (7000) of claim 140 or claim 141 , wherein the first position of interest is an observer and the second position of interest (192) is an observee, and preventing complete visibility across the first obstruction and the second obstruction prevents the observer from seeing the observee.

143. The system (7000) of any one of claims 102 to 142, wherein the multi-region selective-opacity panel (100) comprises a Polymer-Dispersed Liquid Crystal (PDLC) panel and the controller (200) is configured to drive the multi-region selective-opacity panel (100) according to any one of claims 1 to 24.

Images