A non-partitioned continuous gradation PDLC dimming film and a dimming method

Abstract

This application discloses a non-partitioned continuous gradient PDLC dimming film and a dimming method. The PDLC dimming film includes a first transparent conductive layer, a second transparent conductive layer, and a PDLC liquid crystal layer sandwiched between the two. The first transparent conductive layer has a first electrode connected to zero potential at its first end and a second electrode connected to a first power supply voltage at its second end; the second transparent conductive layer has a third electrode connected to zero potential at its first end and a fourth electrode connected to a second power supply voltage at its second end. Under energized conditions, the potential on both transparent conductive layers changes continuously from the first end to the second end, causing the potential difference between the two layers to change continuously from the second end to the first end, thus achieving non-partitioned continuous gradient dimming. This application achieves continuous gradient dimming without physically partitioning the transparent conductive layers, thereby avoiding the process defects introduced by partitioned line cutting, effectively improving product yield and reducing manufacturing costs.

Description

Technical Field

[0001] This application relates to the field of polymer dispersed liquid crystal dimming film technology, and in particular to a non-regional continuous gradient PDLC dimming film and dimming method. Background Technology

[0002] Polymer Dispersed Liquid Crystal (PDLC) dimming film is an electrically controlled dimming device formed by sandwiching a PDLC liquid crystal layer between two transparent conductive layers. In the traditional structure, the two transparent conductive layers are connected to the positive and negative terminals of the driving power supply, respectively. When energized, the trans-film voltage of the entire PDLC dimming film is basically the same. Therefore, this film can only switch between a foggy state and a fully transparent state, and cannot achieve localized or gradual dimming control.

[0003] With the widespread application of PDLC dimming films in automotive sunroofs, taillights, and privacy films, the market demand for local dimming is becoming increasingly urgent. Existing local dimming films mainly achieve independent control of each zone through physical isolation. Structurally, one of the two transparent conductive layers is designated as a common electrode, while the other layer is divided into multiple insulated zone electrodes according to a preset zone pattern. Each zone electrode is connected to a control circuit. The formation of the zone lines mainly employs two process routes: first, after the liquid crystal layer is coated and cured, the zone lines are etched onto the transparent conductive layer using a laser; second, the transparent conductive layer is first etched or cut according to the zone pattern, and then the liquid crystal layer is coated.

[0004] However, the aforementioned physical partition line-based solution has revealed several technical problems in actual production. Incomplete partition line cutting can lead to electrical crosstalk between adjacent partitions, causing unexpected flickering in partitions that should be off; burst defects are prone to occur during the cutting process; and the silver paste electrodes used to collect the current of each partition may shift during coating, resulting in abnormal partition connections. The cumulative effect of these defects manifests as low product yield and high manufacturing costs. Furthermore, the physical partitioning method dictates that there will always be a visually discernible boundary between light and dark areas between adjacent partitions, resulting in a harsh visual effect that cannot meet the application requirements of continuous gradual dimming.

[0005] Therefore, how to achieve flexible dimming control while avoiding the aforementioned defects caused by physical partition lines, and ensuring product yield and controllable manufacturing costs, has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0006] This application addresses the technical problems of existing PDLC dimming films, such as electrical crosstalk between adjacent zones due to incomplete physical zone cutting, burst defects generated during cutting, abnormal zone connections caused by silver paste misalignment, and obvious light-dark boundaries at zone boundaries, which prevent continuous gradient dimming. It provides a zoneless continuous gradient PDLC dimming film and dimming method. The PDLC dimming film includes a first transparent conductive layer, a second transparent conductive layer, and a PDLC liquid crystal layer sandwiched between the two. The PDLC dimming film has a first end and a second end opposite to each other along a first direction. The first transparent conductive layer has a first electrode connected to zero potential at the first end and a second electrode connected to a first power supply voltage at the second end. The second transparent conductive layer has a third electrode connected to zero potential at the first end and a fourth electrode connected to a second power supply voltage at the second end. The first power supply voltage and the second power supply voltage have equal amplitudes and opposite polarities. In the energized state, the potential on both transparent conductive layers changes continuously from the first end to the second end, causing the potential difference between the two layers to change continuously from the second end to the first end, thus achieving zoneless continuous gradient dimming. Continuous gradient dimming can be achieved without physically dividing and cutting the transparent conductive layer, thus avoiding the process defects introduced by section cutting. This effectively improves product yield, reduces manufacturing costs, and avoids the harsh light and dark boundaries between adjacent sections in existing technologies, resulting in a smooth and natural gradient visual effect. The technical solution provided in this application is as follows: On one hand, this application provides a non-zoned continuous gradient PDLC dimming film, comprising: First transparent conductive layer; Second transparent conductive layer; A PDLC liquid crystal layer is sandwiched between the first transparent conductive layer and the second transparent conductive layer; The PDLC dimming film has a first end and a second end opposite to each other along a first direction; The first transparent conductive layer has a first electrode at the first end for connecting to zero potential, and a second electrode at the second end for connecting to the first power supply voltage. The second transparent conductive layer has a third electrode at the first end for connecting to zero potential and a fourth electrode at the second end for connecting to a second power supply voltage. The first power supply voltage and the second power supply voltage have the same amplitude but opposite polarities; When energized, the potential on the first transparent conductive layer changes continuously from the first end to the second end, and the potential on the second transparent conductive layer changes continuously from the first end to the second end, so that the potential difference between the first transparent conductive layer and the second transparent conductive layer changes continuously from the second end to the first end, thereby realizing the PDLC dimming film's undivided continuous gradient dimming along the first direction.

[0007] In some preferred embodiments, the width of the first electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; and / or, the width of the third electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; the second direction is a direction perpendicular to the first direction in the plane of the PDLC dimming film.

[0008] In some preferred embodiments, the width of the second electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; and / or, the width of the fourth electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; the second direction is a direction perpendicular to the first direction in the plane of the PDLC dimming film.

[0009] In some preferred embodiments, the second electrode includes a plurality of first sub-electrodes disposed along the second direction; and / or, the fourth electrode includes a plurality of second sub-electrodes disposed along the second direction.

[0010] In some preferred embodiments, the first electrode and the third electrode are offset from each other in the projection position in the second direction; and / or, the plurality of first sub-electrodes and the plurality of second sub-electrodes are offset from each other in the projection position in the second direction.

[0011] In some preferred embodiments, the first electrode and the second electrode are arranged opposite each other diagonally in the plane of the PDLC dimming film; and / or, the third electrode and the fourth electrode are arranged opposite each other diagonally in the plane of the PDLC dimming film.

[0012] In some preferred embodiments, the first electrode and the third electrode are connected to zero potential via a controllable switch; When the controllable switch is turned on, the potential difference between the first transparent conductive layer and the second transparent conductive layer changes continuously along the first direction, and the PDLC dimming film is in a gradual dimming state. When the controllable switch is turned off, the potential difference between the first transparent conductive layer and the second transparent conductive layer exceeds the start-up voltage of the PDLC liquid crystal layer across the entire surface, and the PDLC dimming film switches to a state of full-surface light transmission.

[0013] In some preferred embodiments, the sheet resistance of the first transparent conductive layer is 50~400Ω / □; and / or the sheet resistance of the second transparent conductive layer is 50~400Ω / □.

[0014] On the other hand, this application also provides a non-zoned continuous gradient dimming method, including: Connect the first electrode and the third electrode to zero potential; A first power supply voltage is applied to the second electrode, and a second power supply voltage is applied to the fourth electrode, wherein the polarity of the second power supply voltage is opposite to that of the first power supply voltage; By adjusting the amplitude of the first power supply voltage and / or the second power supply voltage, the potential difference between the first transparent conductive layer and the second transparent conductive layer changes continuously along the first direction, and the region corresponding to the position where the potential difference exceeds the start-up voltage of the PDLC liquid crystal layer switches from a fog state to a transparent state. As the amplitude of the first power supply voltage and / or the second power supply voltage increases, the transparent region advances from the second end to the first end, achieving continuous gradual light transmission along the first direction.

[0015] In some preferred embodiments, when the amplitudes of the first power supply voltage and the second power supply voltage reach a preset maximum value, the connection between the first electrode and the third electrode and zero potential is disconnected, so that the forced potential gradient on the first transparent conductive layer and the second transparent conductive layer disappears, and the PDLC dimming film remains transparent as a whole.

[0016] By adopting the above technical solution, the non-zoned continuous gradient PDLC dimming film and dimming method provided in this application have the following beneficial effects: 1. This application achieves a continuous distribution of trans-film voltage along a first direction by setting zero-potential electrodes at the first ends of the first and second transparent conductive layers and applying opposite polarity power supply voltages to their second ends. This results in a continuous change in potential between the two transparent conductive layers from the first to the second end, and a continuous change in potential difference between the two layers from the second to the first end. Compared to existing partitioned dimming films that require laser etching to form multiple independent zones with independent electrodes in each zone, this application eliminates the need for etching partitions in the transparent conductive layers. The entire film surface lacks partition lines, achieving a smooth transition from a foggy to a transparent state with continuous gradient dimming without partitions, thus avoiding visual defects caused by partition lines in partitioned dimming films.

[0017] 2. In this application, the first and third electrodes are respectively connected to zero potential via controllable switches. When the controllable switches are on, the first ends of the two transparent conductive layers are fixed at zero potential, and the film operates in gradient dimming mode. When the controllable switches are off, the first and third electrodes are no longer fixed at zero potential, no current flows through the two transparent conductive layers, and each becomes an equipotential body. The trans-film voltage across the entire surface is consistent and higher than the liquid crystal start-up voltage, and the film as a whole switches to a transparent state. Thus, the switching between gradient mode and full-surface transparent mode can be achieved simply by controlling the on / off state of the zero-potential electrodes, without changing the power output method, making the control method simple. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 A cross-sectional schematic diagram of the non-zoned continuous gradient PDLC dimming film provided in the embodiments of this application; Figure 2 A top view of the non-zoned continuous gradient PDLC dimming film provided in an embodiment of this application; Figure 3 This is a schematic diagram showing the comparison between the transparent region and voltage provided in the embodiments of this application.

[0020] The following is supplementary explanation of the attached figures: 10-First transparent conductive layer; 11-First electrode; 12-Second electrode; 20-Second transparent conductive layer; 21-Third electrode; 22-Fourth electrode; 30-PDLC liquid crystal layer. Detailed Implementation

[0021] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0022] The term "an embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of this application. In the description of this application, it should be understood that the terms "upper," "lower," "top," "bottom," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. Moreover, the terms "first," "second," etc., are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein.

[0023] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to an integer, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are included. For example, a specified range from “1 to 10” should be considered to include any and all subranges between the minimum value 1 and the maximum value 10. Exemplary subranges of the range 1 to 10 include, but are not limited to, 1 to 6.1, 3.5 to 7.8, 5.5 to 10, etc.

[0024] like Figure 1 As shown, the first direction is defined as the X direction, which extends along the PDLC dimming film from the first end to the second end; the second direction is the Y direction, which is perpendicular to the X direction in the plane of the PDLC dimming film; the Z direction is the third direction, which is the thickness direction of the PDLC dimming film, and also the direction in which the first transparent conductive layer 10 and the second transparent conductive layer 20 are disposed opposite to each other.

[0025] This application provides a non-regional continuous gradient PDLC dimming film, comprising a first transparent conductive layer 10, a second transparent conductive layer 20, and a PDLC liquid crystal layer 30 stacked sequentially. Optionally, both the first transparent conductive layer 10 and the second transparent conductive layer 20 are made of indium tin oxide (ITO) transparent conductive film.

[0026] The PDLC dimming film has a first end and a second end opposite to each other along a first direction. The first transparent conductive layer 10 has a first electrode 11 at the first end for connecting to zero potential and a second electrode 12 at the second end for connecting to a first power supply voltage. The second transparent conductive layer 20 has a third electrode 21 at the first end for connecting to zero potential and a fourth electrode 22 at the second end for connecting to a second power supply voltage. The first power supply voltage and the second power supply voltage have equal amplitudes but opposite polarities, denoted as +U and -U, respectively. The first end is the side where the zero potential electrode is located, and the second end is the side where the power supply electrode is located.

[0027] When energized, due to the sheet resistance of the first transparent conductive layer 10, the potential on the first transparent conductive layer 10 gradually increases from the first end to the second end, forming a potential distribution that continuously varies from 0 to U along the first direction. Similarly, the potential on the second transparent conductive layer 20 gradually decreases from the first end to the second end, forming a potential distribution that continuously varies from 0 to -U along the second direction. Since the first ends of both transparent conductive layers are at zero potential, while the second ends are at +U and -U respectively, at any position along the first direction, the transmembrane voltage formed between the first transparent conductive layer 10 and the second transparent conductive layer 20 continuously varies from 0V at the first end to 2U at the second end.

[0028] The PDLC liquid crystal layer 30 has a threshold voltage for its transparency transition (e.g., approximately 5V). When the local transfilm voltage exceeds this threshold, the corresponding area transitions from a hazy state to a transparent state; when the local transfilm voltage falls below this threshold, the corresponding area remains hazy. By controlling the amplitude of the first power supply voltage and / or the second power supply voltage, the position where the transfilm voltage reaches the threshold can be adjusted. Specifically, when the first power supply voltage gradually increases from 0V to a certain set voltage value (e.g., 24V), the second power supply voltage correspondingly changes from 0V to the set voltage value (e.g., -24V), and the voltage difference between the two second ends correspondingly increases from 0 to twice the set voltage value (e.g., 48V), the position where the transfilm voltage exceeds the liquid crystal start-up voltage gradually moves from the second end to the first end, and the transparent region correspondingly expands from the second end to the first end, forming a continuous gradient light transmission effect without partitions.

[0029] As a specific implementation method, in order to achieve a more uniform gradient, such as Figure 3As shown, the maximum voltage is set to 48V, and the total rise time is 2s. The voltage starts at 10V, first rising linearly at a low slope to 25.4V, then rising linearly at a high slope to 48V. The first phase lasts 1.6s, and the second phase lasts 0.4s. The low slope is (25.4-10) / 1.6 = 9.625V / s, and the high slope is (48-25.4) / 0.4 = 56.5V / s. By controlling the voltage change rate in segments, the length of the transparent region increases linearly with time, meaning the transparent region increases by the same length per unit time. The low slope segment ensures that the transparent region advances at a uniform speed within the large stroke range of the early stage of the drive, while the high slope segment compensates for the nonlinear shift of the diaphragm caused by the saturation of its physical properties in the later stage of the drive, thereby improving the uniformity and controllability of the gradual change process.

[0030] When the voltage reaches its maximum, if the connection between the zero potential electrode (first electrode 11 and third electrode 21) and the zero potential is disconnected, the first transparent conductive layer 10 and the second transparent conductive layer 20 will no longer maintain the potential gradient. The two layers will become equipotential bodies, and the transfilm voltage of the entire liquid crystal layer will be consistent and higher than the liquid crystal start-up voltage. The entire film will switch to the transparent state.

[0031] Therefore, this application can achieve continuous gradient dimming without physically dividing and cutting the transparent conductive layer, thereby avoiding the process defects introduced by the partition line cutting, effectively improving product yield and reducing manufacturing costs, while avoiding the harsh light and dark boundaries between adjacent partitions in the prior art, and obtaining a smooth and natural gradient visual effect.

[0032] In some preferred embodiments, the width of the first electrode 11 in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; and / or, the width of the third electrode 21 in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; the second direction is a direction perpendicular to the first direction in the plane of the PDLC dimming film.

[0033] The width of the second electrode 12 in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; and / or, the width of the fourth electrode 22 in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; the second direction is a direction perpendicular to the first direction in the plane of the PDLC dimming film.

[0034] The aforementioned length ratio eliminates the need for the electrode to fully cover the entire edge, reducing silver paste usage and material costs while also lowering the processing difficulty associated with full electrode coverage. Furthermore, a length of over 10% ensures sufficient current induction area, preventing the end potential from deviating from the ideal distribution due to excessive contact resistance. When the electrode length is less than 10%, the current concentration effect intensifies, potentially leading to uneven end potential and localized heating. While an electrode length greater than 49% promotes potential uniformity, it significantly increases silver paste usage and process complexity, reducing economic efficiency.

[0035] In some preferred embodiments, the second electrode 12 includes a plurality of first sub-electrodes disposed along the second direction; and / or, the fourth electrode 22 includes a plurality of second sub-electrodes disposed along the second direction. By configuring the power supply electrode as a plurality of sub-electrodes, the potential distribution along the second direction can be made more uniform, reducing the fogging region caused by potential non-uniformity along the electrode length direction.

[0036] In some preferred embodiments, such as Figure 2 As shown, the first electrode 11 and the third electrode 21 are staggered in their projected positions in the second direction; and / or, multiple first sub-electrodes and multiple second sub-electrodes are staggered in their projected positions in the second direction. By staggering the corresponding electrodes on different layers along the second direction, the facing area of ​​the upper and lower electrodes on the vertical projection of the membrane surface can be reduced, local electric field concentration can be reduced, and the permeability uniformity of the membrane can be improved.

[0037] In some preferred embodiments, such as Figure 2 As shown, the first electrode 11 and the second electrode 12 are arranged opposite each other along the diagonal direction in the plane of the PDLC dimming film; and / or, the third electrode 21 and the fourth electrode 22 are arranged opposite each other along the diagonal direction in the plane of the PDLC dimming film.

[0038] In this context, "arranged diagonally" means that the two electrodes are located on opposite sides of the first and second ends of the PDLC dimming film, and are offset from each other in the second direction, so that they are diagonally distributed along the diagonal direction of the film surface, without needing to be strictly located on the geometric diagonal. Specifically, for a rectangular PDLC dimming film, which has four corners, a diagonal direction is formed between one corner of the first end and the opposite corner of the second end. The two electrodes are respectively located at the two edges corresponding to the diagonal, so that the current path between the power electrode and the zero potential electrode intersects within the film surface.

[0039] The above arrangement results in the current paths between the positive and negative power supply electrodes and the zero potential electrode being distributed crosswise within the membrane surface. This is beneficial for balancing the potential distribution on the membrane surface, allowing the potential in the region where each sub-electrode is located to change continuously along the first direction with a gentler gradient. This avoids excessively high or low local transmembrane voltages, thereby further improving the uniformity of the gradient effect.

[0040] In some preferred embodiments, the first electrode 11 and the third electrode 21 are connected to zero potential via a controllable switch (e.g., a MOSFET, a relay, or an electronic switch). When the controllable switch is turned on, the first electrode 11 and the third electrode 21 are connected to zero potential, and the first ends of the first transparent conductive layer 10 and the second transparent conductive layer 20 are no longer fixed at zero potential. At this time, a potential gradient that changes continuously from the first end to the second end is formed on the two transparent conductive layers, and the diaphragm operates in the aforementioned gradient dimming mode.

[0041] When the controllable switch is turned off, the first electrode 11 and the third electrode 21 are no longer connected to zero potential. At this time, since the first transparent conductive layer 10 and the second transparent conductive layer 20 are no longer forced to form a potential gradient, their internal potentials tend to be uniform, and the trans-film voltage across the entire film is approximately equal to the total voltage 2U between the two power supply electrodes. As long as this total voltage is higher than the start-up voltage of the PDLC liquid crystal, the entire film changes from a foggy state to a transparent state, achieving full-surface light transmission. This switching method does not require changing the power supply output method or frequently switching electrode connections; it only requires controlling the on / off state of one or more zero-potential electrodes. The circuit structure is simple and the response speed is fast.

[0042] In some preferred embodiments, the sheet resistance of the first transparent conductive layer is 50~400Ω / □, preferably 140~220Ω / □; and / or, the sheet resistance of the second transparent conductive layer is 50~400Ω / □, preferably 140~220Ω / □. Setting the lower limit of the sheet resistance to not less than 50Ω / □ avoids excessive current flowing through the transparent conductive layer, which could cause it to burn out; setting the upper limit of the sheet resistance to not more than 400Ω / □ ensures a bright, even surface, while also preventing uneven haze caused by excessive voltage distribution in the transparent conductive layer.

[0043] This application also provides a method for continuous gradient dimming without partitions, including the following steps: S1. Connect the first electrode 11 and the third electrode 21 to zero potential (ground). S2. Apply a first power supply voltage to the second electrode 12 and apply a second power supply voltage to the fourth electrode 22. The polarity of the second power supply voltage is opposite to that of the first power supply voltage. S3. By adjusting the amplitude of the first power supply voltage and / or the second power supply voltage, the potential difference between the first transparent conductive layer 10 and the second transparent conductive layer 20 is continuously varied along the first direction. When the potential difference at a certain position exceeds the start-up voltage of the PDLC liquid crystal layer 30, the region corresponding to that position switches from a fog state to a transparent state. Furthermore, as the amplitudes of the first and second power supply voltages gradually increase, the transparent region continuously advances unidirectionally from the second end to the first end, thereby achieving continuous gradual light transmission along the first direction.

[0044] As the amplitudes of the first and second power supply voltages gradually increase, the transparent region continuously advances unidirectionally from the second end to the first end, thereby achieving continuous gradual light transmission along the first direction.

[0045] Specifically, since both the first transparent conductive layer 10 and the second transparent conductive layer 20 have a certain resistance, when the first electrode 11 and the third electrode 21 are grounded, and the second electrode 12 and the fourth electrode 22 are applied with voltages of opposite polarities, a potential gradient continuously distributed along the first direction is formed on each transparent conductive layer. At any location, the potential difference between the first transparent conductive layer 10 and the second transparent conductive layer 20 is the difference in potential between the two layers at that location. Since the voltages applied to the two layers at the second end have opposite polarities, the potential difference at the second end is the largest; while at the first end, both layers are at zero potential, and the potential difference is zero. Therefore, the potential difference gradually decreases along the first direction from the second end to the first end, forming a continuously distributed potential difference.

[0046] When the amplitudes of the first and second power supply voltages are relatively small, only the potential difference in the region near the second end reaches or exceeds the activation voltage of the PDLC liquid crystal layer 30, and this region switches to a transparent state, while the remaining regions remain in a foggy state. As the voltage amplitude gradually increases, the critical position reaching the activation voltage moves continuously from the second end to the first end along the first direction, and the transparent region advances unidirectionally, achieving a continuous gradient light transmission effect without partitions. By precisely controlling the rate and magnitude of voltage amplitude change, the position, width, and transmittance distribution of the gradient transition region can be flexibly adjusted.

[0047] In some preferred embodiments, when the amplitudes of the first and second power supply voltages reach a preset maximum value (e.g., 60V), the connection between the first electrode 11 and the third electrode 21 and zero potential is disconnected, causing the forced potential gradient on the first transparent conductive layer 10 and the second transparent conductive layer 20 to disappear, and the PDLC dimming film remains transparent overall. This allows the PDLC dimming film to flexibly switch between continuous gradient mode and fully transparent mode. When it is necessary to restore gradient dimming, the ground connection is reconnected and the voltage amplitude is adjusted accordingly; the switching process is smooth.

[0048] A zoneless, continuously gradient PDLC dimming film was prepared based on the above technical solution. Actual testing shows that as the driving voltage gradually increases from 0V, the transparent region of the film continuously expands from one side to the other, and no obvious partition lines or light-dark boundaries are observed throughout the process. When the driving voltage reaches its maximum value and the zero-potential electrode is disconnected, the film becomes uniformly transparent with no residual haze. Continuous gradient dimming can be achieved without physical partition lines, and the process is simple and highly reliable.

[0049] The above description is only an optional embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A non-regional continuous gradient PDLC dimming film, characterized in that, include: First transparent conductive layer; Second transparent conductive layer; A PDLC liquid crystal layer is sandwiched between the first transparent conductive layer and the second transparent conductive layer; The PDLC dimming film has a first end and a second end opposite to each other along a first direction; The first transparent conductive layer has a first electrode at the first end for connecting to zero potential and a second electrode at the second end for connecting to the first power supply voltage. The second transparent conductive layer has a third electrode at the first end for connecting to zero potential and a fourth electrode at the second end for connecting to a second power supply voltage. The first power supply voltage and the second power supply voltage have the same amplitude but opposite polarities; When energized, the potential on the first transparent conductive layer changes continuously from the first end to the second end, and the potential on the second transparent conductive layer changes continuously from the first end to the second end, so that the potential difference between the first transparent conductive layer and the second transparent conductive layer changes continuously from the second end to the first end, thereby realizing the PDLC dimming film's undivided continuous gradient dimming along the first direction.

2. The non-regional continuous gradient PDLC dimming film according to claim 1, characterized in that, The width of the first electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; and / or, the width of the third electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; the second direction is a direction perpendicular to the first direction in the plane of the PDLC dimming film.

3. The non-regional continuous gradient PDLC dimming film according to claim 1, characterized in that, The width of the second electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; and / or, the width of the fourth electrode in the second direction accounts for 10% to 49% of the width of the PDLC dimming film in the second direction; the second direction is a direction perpendicular to the first direction in the plane of the PDLC dimming film.

4. The partitionless continuous gradient PDLC dimming film according to claim 2 or 3, characterized in that, The second electrode includes a plurality of first sub-electrodes disposed along the second direction; and / or, the fourth electrode includes a plurality of second sub-electrodes disposed along the second direction.

5. The non-regional continuous gradient PDLC dimming film according to claim 4, characterized in that, The first electrode and the third electrode are offset from each other in the projection position in the second direction; and / or, the plurality of first sub-electrodes and the plurality of second sub-electrodes are offset from each other in the projection position in the second direction.

6. The partitionless continuous gradient PDLC dimming film according to claim 1, characterized in that, The first electrode and the second electrode are arranged opposite each other diagonally in the plane of the PDLC dimming film; and / or, the third electrode and the fourth electrode are arranged opposite each other diagonally in the plane of the PDLC dimming film.

7. The non-regional continuous gradient PDLC dimming film according to claim 1, characterized in that, The first electrode and the third electrode are connected to zero potential via a controllable switch; When the controllable switch is turned on, the potential difference between the first transparent conductive layer and the second transparent conductive layer changes continuously along the first direction, and the PDLC dimming film is in a gradual dimming state. When the controllable switch is turned off, the potential difference between the first transparent conductive layer and the second transparent conductive layer exceeds the start-up voltage of the PDLC liquid crystal layer across the entire surface, and the PDLC dimming film switches to a state of full-surface light transmission.

8. The non-regional continuous gradient PDLC dimming film according to claim 1, characterized in that, The sheet resistance of the first transparent conductive layer is 50~400Ω / □; and / or the sheet resistance of the second transparent conductive layer is 50~400Ω / □.

9. A non-regional continuous gradient dimming method, applied to the non-regional continuous gradient PDLC dimming film as described in any one of claims 1-8, characterized in that, Includes the following steps: Connect the first electrode and the third electrode to zero potential; A first power supply voltage is applied to the second electrode, and a second power supply voltage is applied to the fourth electrode, wherein the polarity of the second power supply voltage is opposite to that of the first power supply voltage; By adjusting the amplitude of the first power supply voltage and / or the second power supply voltage, the potential difference between the first transparent conductive layer and the second transparent conductive layer changes continuously along the first direction, and the region corresponding to the position where the potential difference exceeds the start-up voltage of the PDLC liquid crystal layer switches from a fog state to a transparent state. As the amplitude of the first power supply voltage and / or the second power supply voltage increases, the transparent region advances from the second end to the first end, achieving continuous gradual light transmission along the first direction.

10. The non-zoned continuous gradient dimming method according to claim 9, characterized in that, When the amplitudes of the first power supply voltage and the second power supply voltage reach the preset maximum value, the connection between the first electrode and the third electrode and zero potential is disconnected, so that the forced potential gradient on the first transparent conductive layer and the second transparent conductive layer disappears, and the PDLC dimming film as a whole remains transparent.

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