Bidirectional transparent display system

Abstract

Displays, systems, and methods of manufacture including a sparse array of light emitting diodes (LEDs) are disclosed. The display includes a panel having at least one tile configured to display information. The panel is disposed within or on the transparent material. Each tile includes an array of LEDs having a uniform distance therebetween such that light from the array is viewable on opposite sides of the panel while providing visibility through the panel. A darkening layer on at least one side of the panel provides selectable darkening to block light from exiting the at least one side of the panel.

Description

[0001] priority

[0002] This patent application claims the benefit of priority to U.S. Provisional Patent Application Serial No. 63 / 352,517 filed on June 15, 2022 and U.S. Provisional Patent Application Serial No. 63 / 420,872 filed on October 31, 2022, each of which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure relates to sparse light emitting diode (LED) arrays, systems, and applications. Background Art

[0004] LEDs provide a highly efficient and relatively small light source compared to traditional light sources. The use of LEDs has evolved from systems that provide pure illumination to more complex systems that use the light in a variety of ways rather than just providing area lighting. As a result, efforts are underway to improve the technology for using LED arrays, as well as to find additional uses for LED arrays. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 A cross-sectional side view of an example of a light source is shown.

[0006] Figure 2 It shows that it can include Figure 1 A block diagram of an example of a light source visualization system.

[0007] Figure 3 and Figure 4 Shows Figure 1 Figures showing side views of a light source in various stages of assembly.

[0008] Figure 5A-5D Cross-sectional views of sparse arrays of LEDs according to some examples are respectively shown.

[0009] Figure 6 Shown is a top view of an example panel in accordance with various embodiments of the disclosed subject matter.

[0010] Figure 7 An example of a panel having a single tile is shown in accordance with various embodiments of the disclosed subject matter.

[0011] Figure 8A-8B An example of a panel having multiple display tiles in accordance with various embodiments of the disclosed subject matter is shown.

[0012] Fig. 9A and Fig. 9B Examples of sparse LED array arrangements according to various embodiments of the disclosed subject matter are shown.

[0013] Fig.10 An example display is shown in accordance with various embodiments of the disclosed subject matter.

[0014] Fig.11 An example system in accordance with various embodiments of the disclosed subject matter is shown.

[0015] Fig.12 An example of a general device in accordance with some embodiments is shown.

[0016] Figure 13A-13G Process operations for fabricating a sparse array are shown in accordance with some embodiments.

[0017] Fig.14 Shown according to Figure 13A-13G The process operations shown in FIG. 1 are examples of methods for manufacturing sparse arrays.

[0018] Fig.15 An example of a process providing improved contrast ratio according to some embodiments is shown.

[0019] Fig.16 An example display stackup according to various embodiments of the disclosed subject matter is shown.

[0020] Throughout the several views, corresponding reference numerals indicate corresponding parts. The elements in the drawings are not necessarily drawn to scale. The configurations shown in the drawings are merely examples and should not be construed as limiting in any way. DETAILED DESCRIPTION

[0021] The use of transparent displays enabled by micro-LEDs as described herein may be able to expand the capabilities of the user experience by providing signage, interactive menus, entry criteria, public information, and many other scenarios. For example, the user experience may be enhanced by allowing rich augmented reality (AR) and / or virtual reality (VR) experiences, entertainment, and many other scenarios. Multi-display functionality may be provided with the same display, which is achieved by effectively being able to produce images of similar quality on both sides thereof, thus effectively creating a bidirectional display that may be used in a variety of consumer, industrial, and commercial settings.

[0022] For the purposes of this document, the term "micro-LED" is intended to be synonymous with an LED in a sparse array of LEDs as defined herein. Efforts are currently underway to improve micro-LED display technology. For example, displays such as direct-view displays and projection displays can use micro-LEDs to improve efficiency and increase brightness.

[0023] In a direct-view micro-LED display, the LEDs may occupy a relatively small share of the display area. Because most of the display area is unaffected by the LEDs, the LEDs may not substantially change the optical properties of the surface on which they are assembled. For example, in the presence of LEDs mounted on a black surface, the black surface may remain black. Similarly, in the presence of LEDs mounted on a reflective surface, the reflective surface may remain reflective. Other examples and optical surface properties may also be used.

[0024] In some examples, micro-LEDs can be assembled onto transparent and / or flexible substrates. The transparent flexible substrate can then be laminated onto a substrate having desired optical properties (such as reflectivity, etc.). Using a transparent flexible substrate in this manner can allow micro-LEDs to be applied to curved or irregularly shaped substrates, which may be incompatible with micro-LED assembly techniques using rigid flat substrates (such as wafers).

[0025] In some examples, the flexible substrate can be laminated to the substrate with the LED side facing down using a transparent adhesive having a thickness sufficient to encapsulate the micro-LEDs. For these and other examples, the transparent substrate and adhesive can also serve as a barrier that can protect the micro-LEDs from environmental influences. Because the transparent substrate can provide protection for the micro-LEDs, the transparent substrate can reduce or eliminate the need to use an additional transparent cover or protective layer to provide protection for the micro-LEDs.

[0026] Figure 1 A cross-sectional side view of an example of a light source 100 is shown. The light source 100 can include a sparse array of LEDs 102 (e.g., "micro-LEDs") disposed on a transparent flexible substrate 104 and a rigid substrate 106 adhered to the transparent flexible substrate 104 with an adhesive layer 108 such that the sparse array of LEDs 102 is located between the rigid substrate 106 and the transparent flexible substrate 104. The sparse array of LEDs 102 can be encapsulated in an adhesive 110 of the adhesive layer 108.

[0027] The transparent flexible substrate 104 may be a polymer sheet having a relatively high transmittance, or equivalently, a relatively low loss, due to absorption and scattering in the visible portion of the electromagnetic spectrum, such as between wavelengths of about 400 nm and about 700 nm. Suitable materials for the transparent flexible substrate 104 may include transparent polyimide (PI), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), etc. The transparent flexible substrate 104 may have a thickness between about 20 μm and about 200 μm, although thicknesses outside this thickness range may also be used.

[0028] A sparse array of LEDs 102 may be disposed on a transparent flexible substrate 104. For purposes of this document, the term "sparse" is intended to mean that the light generating surface area of ​​the array is less than or significantly less than the total surface area of ​​the array. For example, the fill factor (e.g., the ratio of the light generating surface area to the total surface area) of the array may be less than or equal to a specified threshold, such as 10%, 5%, 4%, 3%, 2%, 1%, or another suitable threshold. As a specific example, the LEDs 102 may be arranged in a rectangular array, where the center-to-center spacing along one dimension is represented by the spacing x. Each LED 102 may have a light generating area sized along one dimension by a dimension s. The ratio of s divided by x may be less than or equal to 0.1. In the orthogonal dimension, a similar ratio applies, where the linear dimension of the light generating area is less than or equal to one-tenth of the linear center-to-center spacing of the LEDs 102. Combining the two linear dimensions, the surface area of ​​the light generating area of ​​the LEDs 102 is less than or equal to 1% of the surface area of ​​the array. In some examples, the light generating area of ​​each LED may be less than 200 μm on a side. In some examples, the light generating area of ​​each LED can be less than 50 μm on a side. Electrical traces can be deposited on the transparent flexible substrate 104 to power the LEDs 102 (e.g., deliver current to and from the LEDs 102). In some examples, the electrical traces can be metal traces that are narrow enough to be invisible under typical viewing conditions. In some examples, the electrical traces can be formed of one or more transparent conductive materials, such as indium tin oxide (ITO). Note that the terms "substantially transparent" and "transparent" are used interchangeably herein to refer to materials (such as metal oxides or very thin metals) through which light from the micro-LEDs passes without being substantially (more than a few percent) absorbed or reflected. Each of these examples of electrical traces (e.g., narrow metal traces and transparent conductive materials) can be considered to provide transparent electrical traces.

[0029] In some examples, a sparse array of LEDs 102 may include two or more LEDs 102 that emit light at the same wavelength (or color). In some examples, a sparse array of LEDs 102 may include LEDs 102 that all emit light at the same wavelength. For example, a device such as a display may include a sparse array of LEDs 102 that all emit red light, a sparse array of LEDs 102 that all emit green light, and a sparse array of LEDs 102 that all emit blue light. In some examples, a sparse array of LEDs 102 may include two or more LEDs 102 that emit light at different wavelengths. For example, a device such as a display may include a sparse array of LEDs 102, some of which emit red light, some of which emit green light, and some of which may emit blue light. The red, green, and blue LEDs 102 may be arranged in repeating clusters, where each cluster forms a color pixel of the device. In some examples, the sparse array of LEDs 102 can include at least one LED that emits light at a visible wavelength (e.g., between about 400 nm and about 700 nm). In some examples, the sparse array of LEDs 102 can include at least one LED that emits light at an infrared wavelength (e.g., greater than about 700 nm). Such infrared wavelengths can be used for biometric sensing or other sensing techniques.

[0030] Because the sparse array of LEDs 102 (including the light emitting areas of the LEDs 102, corresponding electrical traces, and any corresponding circuitry) can have a relatively small fill factor, a majority of the surface area of ​​the sparse array of LEDs 102 can be transparent. For example, light incident on the sparse array of LEDs 102 (or incident from or on the transparent flexible substrate 104) mostly passes through the sparse array of LEDs 102, with only a relatively small portion being blocked by the light emitting areas and electrical traces of the sparse array of LEDs 102.

[0031] As a result, a sparse array of LEDs 102 can generate light on a surface and / or optical element (such as on a rigid substrate 106 described below) with additional functionality. For example, the surface and / or optical element can include a reflector with a specified reflectivity value. As another example, the surface and / or optical element can include a spectral filter with a specified reflectivity, transmittance, or absorptivity at one or more specified wavelengths. Other suitable functionality can also be used.

[0032] The rigid substrate 106 may be adhered to the transparent flexible substrate 104 .

[0033] In some examples, the rigid substrate 106 can be transparent. Suitable applications for the transparent rigid substrate 106 can include building windows, head-up displays, augmented reality headsets, etc. Suitable transparent materials for the transparent rigid substrate 106 can include glass, laminated glass, polycarbonate, or engineered plastics such as polymethyl methacrylate (PMMA).

[0034] In some examples, the rigid substrate 106 can be reflective. In some examples, the rigid surface can be specularly reflective (e.g., can have a relatively smooth reflective surface that causes relatively little scattering or diffusion when reflected). Suitable applications for the reflective rigid substrate 106 can include mirrors, such as vehicle rearview mirrors or side mirrors that can display information. Specifically, the specular reflective surface of the rigid substrate 106 can perform the function of reflecting light from the rear of the vehicle, and the sparse array of LEDs 102 can display information superimposed on the reflected light.

[0035] In some examples, rigid substrate 106 may be protective and / or decorative, such as a housing material for a mobile device such as a smartphone. Rigid substrate 106 may include other suitable optical properties, and also perform other suitable functions.

[0036] The rigid substrate 106 can be flat (e.g., substantially flat) or curved. The curved substrate can be used in a vehicle windshield, an augmented reality headset, a wearable device, or other suitable device. In some examples, the rigid substrate 106 is formed as a single unitary body. In other examples, the rigid substrate 106 can include multiple rigid substrate elements. For example, multiple rigid substrate elements can be used to create a folding display in a smartphone or other mobile device. As described below, a custom tool can support such a curved substrate during a lamination process.

[0037] The adhesive can adhere the rigid substrate 106 to the transparent flexible substrate 104. In some examples, the adhesive can be formed into an adhesive layer 108 so that the sparse array of LEDs 102 is located between the rigid substrate 106 and the transparent flexible substrate 104. Other suitable configurations can also be used. Suitable materials for the adhesive of the adhesive layer 108 can include silicone, epoxy silicone, acrylic film, epoxy film, etc.

[0038] In some examples, the adhesive of the adhesive layer 108 may be formed of a material having a refractive index that may match or substantially match the refractive index of the transparent flexible substrate 104 and / or the rigid substrate 106, or may be formed of a material having a refractive index that may be between the refractive indexes of the transparent flexible substrate 104 and the rigid substrate 106. Selecting the refractive index in this manner may reduce or eliminate reflections at the interface between the adhesive layer 108 and the transparent flexible substrate 104 and / or at the interface between the adhesive layer 108 and the rigid substrate 106. For example, the adhesive of the adhesive layer 108 may be formed of a material having a refractive index between about 1.4 and about 1.7. Using a refractive index in the range of about 1.4 to about 1.7 may reduce unwanted reflections between the adhesive layer 108 and the transparent flexible substrate 104 and unwanted reflections between the adhesive layer 108 and the rigid substrate 106. An optional thin film anti-reflective coating may also be used to help reduce or eliminate unwanted reflections at one or more interfaces between adjacent different materials or between a material and air.

[0039] In some examples, bonding layer 108 can fully encapsulate the sparse array of LEDs 102. By fully encapsulating the sparse array of LEDs 102, bonding layer 108 can protect the sparse array of LEDs 102 from environmental impacts and can form a smooth, unbroken interface with rigid substrate 106. To fully encapsulate the sparse array of LEDs 102, the adhesive of bonding layer 108 can have a sufficiently low resin viscosity so that the adhesive flows around LEDs 102 when deposited. In addition, to fully encapsulate the sparse array of LEDs 102, bonding layer 108 can be thick enough to fully cover the topography of the sparse array of LEDs 102.

[0040] Figure 2 It shows that it can include Figure 1 1 is a block diagram of an example of a visualization system 10 of a light source 100. The visualization system 10 may include a wearable housing 12, such as a headset or goggles. The housing 12 may mechanically support and accommodate the elements detailed below. In some examples, one or more of the elements detailed below may be included in one or more additional housings that may be separated from the wearable housing 12 and may be coupled to the wearable housing 12 wirelessly and / or via a wired connection. For example, a separate housing may reduce the weight of the wearable goggles, such as by including batteries, radios, and other elements. The housing 12 may include one or more batteries 14 that may power any or all of the elements detailed below. The housing 12 may include circuitry that may be electrically coupled to an external power source, such as a wall outlet, to charge the battery 14. The housing 12 may include one or more radios 16 to wirelessly communicate with a server or network via a suitable protocol, such as WiFi.

[0041] The visualization system 10 may include one or more sensors 18, such as optical sensors, audio sensors, tactile sensors, thermal sensors, gyroscope sensors, time-of-flight sensors, triangulation-based sensors, and the like. In some examples, one or more of these sensors may sense the location, position, and / or orientation of the user. In some examples, one or more of the sensors 18 may generate a sensor signal in response to the sensed location, position, and / or orientation. The sensor signal may include sensor data corresponding to the sensed location, position, and / or orientation. For example, the sensor data may include a depth map of the surrounding environment. In some examples, such as for an augmented reality system, one or more of the sensors 18 may capture real-time video images of the surrounding environment near the user.

[0042] The visualization system 10 may include one or more video generation processors 20. The one or more video generation processors 20 may receive scene data representing a three-dimensional scene from a server and / or a storage medium, such as a set of position coordinates of an object in the scene or a depth map of the scene. The one or more video generation processors 20 may receive one or more sensor signals from one or more sensors 18. In response to the scene data representing the surrounding environment and at least one sensor signal representing the location and / or orientation of the user relative to the surrounding environment, the one or more video generation processors 20 may generate at least one video signal corresponding to a view of the scene. In some examples, the one or more video generation processors 20 may generate two video signals, one for each eye of the user, the two video signals representing views of the scene from the perspective of the left eye and the right eye of the user, respectively. In some examples, the one or more video generation processors 20 may generate more than two video signals and combine the video signals to provide one video signal for both eyes, two video signals for both eyes, or other combinations.

[0043] The visualization system 10 may include one or more light sources 22 (such as Figure 1 Light source 100). Suitable light sources 22 may include light emitting diodes, monolithic light emitting diodes, multiple light emitting diodes, light emitting diode arrays, light emitting diode arrays disposed on a common substrate, segmented light emitting diodes disposed on a single substrate and having individually addressable and controllable (and / or controllable in groups and / or molecular sets) light emitting diode elements, micro light emitting diode (micro-LED) arrays, etc. In some examples, one or more of light sources 22 may include a sparse array of LEDs disposed on a transparent flexible substrate, and a rigid substrate adhered to the transparent flexible substrate using an adhesive layer, such that the sparse array of LEDs is located between the rigid substrate and the transparent flexible substrate.

[0044] The light emitting diode may be a white light emitting diode. For example, the white light emitting diode may emit excitation light, such as blue light or violet light. The white light emitting diode may include one or more phosphors that may absorb some or all of the excitation light and, in response, may emit phosphor light (such as yellow light) having a wavelength greater than the wavelength of the excitation light.

[0045] One or more light sources 22 may include light generating elements having different colors or wavelengths. For example, the light source may include a red light emitting diode that may emit red light, a green light emitting diode that may emit green light, and a blue light emitting diode that may emit blue light. The red light, green light, and blue light are combined in a particular ratio to produce any suitable color that is visually perceptible in the visible portion of the electromagnetic spectrum.

[0046] The visualization system 10 may include one or more modulators 24. The modulators 24 may be implemented in one of at least two configurations.

[0047] In a first configuration, modulator 24 may include circuitry that can directly modulate light source 22. For example, light source 22 may include an array of light emitting diodes, and modulator 24 may directly modulate the electrical power, voltage, and / or current directed to each light emitting diode in the array to form modulated light. Modulation may be performed in an analog manner and / or in a digital manner. In some examples, light source 22 may include an array of red light emitting diodes, an array of green light emitting diodes, and an array of blue light emitting diodes, and modulator 24 may directly modulate the red light emitting diodes, the green light emitting diodes, and the blue light emitting diodes to form modulated light to produce a particular image.

[0048] In a second configuration, the modulator 24 may include a modulation panel, such as a liquid crystal panel. The light source 22 may generate uniform illumination or near uniform illumination to illuminate the modulation panel. The modulation panel may include pixels. Each pixel may selectively attenuate a corresponding portion of the modulation panel area in response to an electrical modulation signal to form modulated light. In some examples, the modulator 24 may include a plurality of modulation panels that may modulate light of different colors. For example, the modulator 24 may include a red modulation panel that may attenuate red light from a red light source (such as a red light emitting diode), a green modulation panel that may attenuate green light from a green light source (such as a green light emitting diode), and a blue modulation panel that may attenuate blue light from a blue light source (such as a blue light emitting diode).

[0049] In some examples of the second configuration, the modulator 24 may receive uniform white light or nearly uniform white light from a white light source, such as a white light emitting diode. The modulation panel may include a wavelength selective filter on each pixel of the modulation panel. The panel pixels may be arranged in groups, such as three or four groups, where each group may form a pixel of a color image. For example, each group may include a panel pixel with a red filter, a panel pixel with a green filter, and a panel pixel with a blue filter. Other suitable configurations may also be used.

[0050] The visualization system 10 may include one or more modulation processors 26 that may receive a video signal (such as from one or more video generation processors 20) and in response may generate an electrical modulation signal. For configurations in which the modulator 24 directly modulates the light source 22, the electrical modulation signal may drive the light source 24. For configurations in which the modulator 24 includes a modulation panel, the electrical modulation signal may drive the modulation panel.

[0051] The visualization system 10 may include one or more beam combiners 28 (also referred to as beam splitters 28) that may combine light beams of different colors to form a single polychromatic light beam. For configurations in which the light source 22 may include a plurality of light emitting diodes of different colors, the visualization system 10 may include one or more wavelength-sensitive (e.g., dichroic) beam splitters 28 that may combine light of different colors to form a single polychromatic light beam.

[0052] The visualization system 10 can direct the modulated light toward the eyes of the viewer in one of at least two configurations. In the first configuration, the visualization system 10 can be used as a projector and can include suitable projection optics 30 that can project the modulated light onto one or more screens 32. The screen 32 can be positioned at a suitable distance from the user's eyes. The visualization system 10 can optionally include one or more lenses 34 that can position a virtual image of the screen 32 at a suitable distance from the eyes, such as a close-focus distance, such as 500mm, 750mm, or another suitable distance. In some examples, the visualization system 10 can include a single screen 32 so that the modulated light can be directed toward both eyes of the user. In some examples, the visualization system 10 can include two screens 32 so that the modulated light from each screen 32 can be directed toward the corresponding eye of the user. In some examples, the visualization system 10 can include more than two screens 32. In a second configuration, the visualization system 10 can direct the modulated light directly into one or both eyes of the viewer. For example, projection optics 30 may form an image on the retina of one eye of a user, or may form an image on each retina of both eyes of a user.

[0053] For some configurations of the augmented reality system, the visualization system 10 may include an at least partially transparent display so that the user can view the user's surroundings through the display. For such configurations, the augmented reality system may generate modulated light corresponding to an enhancement of the surroundings, rather than the surroundings themselves. For example, in the example of a retailer displaying chairs, the augmented reality system may direct modulated light corresponding to the chairs, rather than the rest of the room, toward the screen or toward the user's eyes.

[0054] Figure 3 and Figure 4 Shows Figure 1 1 and 2. Side views of light source 100 in various stages of assembly. Assembling light source 100 in this manner can help avoid air occlusions that can degrade the appearance and optical performance of the finished device. Other assembly techniques can also be used.

[0055] exist Figure 3 In the embodiment of the present invention, a sparse array of LEDs 102 has been arranged (e.g., mounted, grown, deposited, or otherwise formed) on a transparent flexible substrate 104. The transparent flexible substrate 104 has been removably mounted in or on a frame 302. A laminating tool 304 can advance the frame 302 toward an adhesive layer 306 that has been deposited on a support film 308. Alternatively, the laminating tool 304 can advance the adhesive layer 306 toward the frame 302, or advance the two toward each other. The sparse array of LEDs 102 will contact the adhesive layer 306 that has been deposited on the support film 308. The adhesive of the adhesive layer 306 can be in a solid form at room temperature. The adhesive has been applied to the support film 308 and has been covered by a cover film (not shown). A vacuum laminator having a temperature range that allows the adhesive to flow and conformally cover the topography of the LED array can laminate the adhesive layer 306 to the sparse array of LEDs 102 to encapsulate the sparse array of LEDs 102 in the adhesive layer 108. After lamination, the support film 308 may then be removed.

[0056] exist Figure 4 In the lamination tool 404 (optionally, with Figure 3106 ) can advance the transparent flexible substrate 104 and the adhesive layer 108 toward the rigid substrate 106, wherein the sparse array of LEDs 102 is encapsulated in the adhesive layer 108. Alternatively, the lamination tool 404 can advance the rigid substrate 106 toward the transparent flexible substrate 104 and the adhesive layer 108, or toward each other. The lamination tool can laminate the adhesive layer 108 onto the rigid substrate 106, wherein the sparse array of LEDs 102 is encapsulated in the adhesive layer 108. After the adhesive layer 108 has been laminated to the rigid substrate 106, the entire layered structure can be subjected to temperature cycling, exposure to ultraviolet light, or other suitable curing techniques to cure the adhesive.

[0057] In the above example, the transparent flexible substrate 104 has been laminated with the LED side facing the rigid substrate 106, so that the LED 102 is located between the two substrates and encapsulated by the adhesive. Alternatively, the transparent flexible substrate 104 can be laminated with the LED side facing away from the rigid substrate 106, so that the LED 102 is exposed, and the transparent flexible substrate 104 is located between the exposed LED 102 and the rigid substrate 106.

[0058] In some examples, additional components can be assembled onto the transparent flexible substrate, such as integrated circuits (ICs), micro ICs, or transistors for display backplanes. In addition, additional layers can be integrated into the device to form a capacitive or resistive touch screen.

[0059] In some embodiments, the LED includes a plurality of semiconductor layers grown on a substrate (e.g., a sapphire substrate) that will be fabricated into pixels. The substrate can be any substrate capable of growing an epitaxial layer thereon, such as sapphire. The substrate can have a pattern on which an epitaxial layer is grown. The pixel can be formed of gallium nitride (GaN), having an n-type semiconductor, a p-type semiconductor, and an active region between the n-type semiconductor and the p-type semiconductor adjacent to the substrate. The active region can be, for example, a multi-quantum well structure in which light emitted from the pixel is generated. After processing, in some embodiments, the substrate can be removed.

[0060] Prior to etching the epitaxial GaN layer, a die layer of a chip scale package (CSP) that allows for uniform current distribution and optical coupling may be deposited or otherwise formed. For example, uniform current injection in a p-type semiconductor may be obtained by depositing a transparent conductive oxide (TCO) layer such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), or tin oxide (SnO) on the p-type semiconductor. Each of these TCO layers may be considered a transparent coating.

[0061] Figure 5AA cross-sectional view of a sparse array of LEDs 500a according to some examples is shown. LED 500a may include an epitaxial stack 510 of n-type and p-type semiconductors (e.g., GaN, InGaN, AlInGaP, GaAs, InGaAs). The thickness of epitaxial stack 510 may range from about 3 μm to about 15 μm, typically about 5 μm. The n-type semiconductor and p-type semiconductor of epitaxial stack 510 may be electrically contacted with traces 514 on substrate 516 via n-contact 512a and p-contact 512b, respectively. The n-contact 512a and p-contact 512b (or interconnect material) may be formed of a metal or compound, such as Au, Sn, AuSn, In, anisotropic conductive film (ACF) / ACInk, self-aligned contact (SAC). The thickness of n-contact 512a and p-contact 512b may range from about 0.02 μm to about 5 μm, typically about 0.1 μm. The trace 514 may be formed of a TCO material. The thickness of the trace 514 may range from about 0.5 μm to about 10 μm, typically about 1 μm. The n-contact 512a and the p-contact 512b may be patterned and formed of a metal such as copper (Cu), nickel (Ni), gold (Au), silver (Ag), and / or titanium (Ti), which may be deposited on the epitaxial stack 510, for example. The substrate 516 may be a rigid or flexible substrate as described above, formed of, for example, glass, PET, polyamideimide, polyetherimide, or transparent polyimide. The thickness of the substrate 516 may range from about 50 μm to about 1000 μm, typically about 100 μm. The metal conductor 518 may make contact with the trace 514 to route power and other signals to the epitaxial stack 510. The metal conductor 518 may be formed of a metal or compound such as Au, Cu, Al, Ti, Ni, or Mo. The thickness of metal conductor 518 may range from about 0.5 μm to about 30 μm, typically about 1 μm.

[0062] In some embodiments, light conversion layer 520 containing phosphor particles may be disposed on or adjacent to epitaxial stack 510. For example, light conversion layer 520 may convert light emitted by epitaxial stack 510 into white light.

[0063] As shown, lens 530 and / or other optical elements can be disposed above epitaxial stack 510. Lens 530 and / or other optical elements can be bonded in a bonding layer. Although not shown, another substrate can be disposed on lens 530.

[0064] Figure 5B FIG. 5 shows a cross-sectional view of another sparse array of LEDs 500b according to some examples. As indicated, Figure 5B LED 500b and Figure 5AThe difference between LED 500a and LED 500a is the presence of submount 522 (for convenience, the optional light conversion layer 520 and lens 530 are not included). Figure 5B ). The base 522 may be a rigid substrate formed, for example, of glass or silicon. The thickness of the base 522 may range from about 5 μm to about 100 μm, typically about 20 μm. The interconnect material may be the same on both sides of the base 522.

[0065] In some embodiments, the minimum xy dimension of the vertically singulated LEDs can be about 3 μm by about 3 μm, and the maximum xy dimension can be about 15 μm by about 15 μm. In various embodiments, the minimum xy dimension of the lateral and flip-chip LEDs can be about 3 μm by about 6 μm, and the maximum xy dimension can be about 50 μm by about 75 μm. In this case, a 127 μm by 127 μm panel has 200 pixels per inch (PPI), has a 40×40 μm micro-IC, a 25×25 μm LED base, 2×10 μm by 127 μm traces to supply the micro-IC, 2×10 μm by <50 μm traces to supply the LEDs, and the total opaque or translucent area of ​​the tile is 5765 μm 2 , the total area of ​​each pixel in 200ppi is 16129μm 2 , and the fractional area is 35% covered and 65% transparent. Similarly, a 362μm×362μm panel with 70 pixels per inch (PPI) has a 40×40μm micro-IC, a 25×25μm LED base, 2×10μm×362μm traces to supply the micro-IC, and 2×10μm×<150μm traces to supply the LEDs, with a total opaque or translucent area of ​​the tile of 12465μm 2 , the total area of ​​each pixel at 70ppi is 131044μm 2 , and the fractional area is 10% covered and 90% transparent. Any of these can provide sufficient transparency for the panel to be seen through the panel. That is, in a sparse display, the distance between the LEDs of the sparse array of LEDs allows for display of at least one of alphanumeric and image information while providing visibility through the transparent material.

[0066] As described above, displays have always had a viewing side that emits light and a side full of electronics and components that operate to produce light and images. Transparent displays enabled by micro-LEDs can have an emitting side and a backplane side. In some applications, it may be desirable to emit light from one side of the display and not emit light from the opposite side; however, in other applications, this limitation may be impractical, and true light leakage prevention can be addressed by means other than inherent design. In the current embodiments described herein, the ideal surface for transparent display integration can have utility from the outside in and from the inside out, and in many use cases, these are exclusive. Therefore, displays that can provide images of similar quality from both sides can greatly enhance the utility of displays while effectively utilizing their size and integration efforts.

[0067] Figure 5C A cross-sectional view of another sparse array of LEDs is shown according to some examples. Figure 5C The flip chip or lateral LED 500c can be a micro-LED that emits substantially equivalently from both sides, meaning that transparent contacts and regions exist on both the n-side and the p-side of the structure to make electrical contact with both the n-side and the p-side of the structure. Figure 5C As shown in , LED 500c may include a p-type semiconductor 532a and an n-type semiconductor 532b on opposite sides of an active region 532c that may include a multi-quantum well structure. A transparent contact 534a may be provided on the p-type semiconductor 532a. Similarly, a transparent protective coating 536 or pattern that mimics the transparent contact 534a may be formed on the n-type semiconductor 532b. The p-type semiconductor 532a and the active region 532c may be etched to expose a portion of the n-type semiconductor 532b. A transparent (or non-transparent) contact 534b may be formed on the exposed portion of the n-type semiconductor 532b. Thus, the display backplane may be substantially transparent, including a main emission region and a majority of conductive traces connected to the emission region. Examples of candidate materials include glass, PET, polyamide-imide, polyetherimide, or transparent polyimide for substrates, and ITO or ZnO for conductive traces. The transparent contact may be, for example, a very thin metal, such as Ni at a thickness of 50-80 angstroms. Other thin metals may also be used, such as, for example, Al, Ti, Au, Ag, Mo. An interconnect or bonding system for the LED to the backplane may also be used that is substantially transparent and has well-controlled transmission.

[0068] Note that it may be desirable to have approximately the same % transmission between the top and bottom of the LED, regardless of die type (vertical or lateral / flip chip as described). In the case of a flip chip LED, a wide contact (e.g., ITO / Ag) may be used on the mesa for the p-contact, and since the opposite side of the device may typically have no contacts, and thus no metal on that surface, a layer (transparent protective coating 536 or pattern) may be used to make the transmission equivalent to the surface of the contacts. The transparent protective coating 536 or pattern may be similar to the metal of the actual contacts, but may also be different (e.g., a metal or oxide or a combination of both may be used).

[0069] Figure 5D A cross-sectional view of another sparse array of LEDs is shown according to some examples. Figure 5D The vertical LED 500d includes a p-type semiconductor 542a and an n-type semiconductor 542b on opposite sides of an active region 542c which may include a multi-quantum well structure. Transparent contacts 544a, 544b may be disposed on the p-type semiconductor 542a and the n-type semiconductor 542b, respectively. Figure 5C and Figure 5D The active regions 532c, 542c emit in all directions, so light can be Figure 5C and Figure 5D Both the transparent contacts and the coating (if any) in the structure emit.

[0070] although Figure 5C and Figure 5D Not shown, but there may be other layers, such as reflective material deposited or otherwise formed on the sidewalls of the semiconductor structure to limit light emitted from the active area from being emitted by the edge of the semiconductor structure. That is, light emitted from the active area is substantially all emitted from the surface of the semiconductor structure in the growth direction of the semiconductor structure (i.e., in the direction between the transparent contacts). The reflective material may be formed of one or more metal layers (e.g., Cu) or a multilayer Bragg reflector structure including, for example, oxide layers of different refractive indices.

[0071] Figure 6A top view of an example panel 600 is shown. The panel 600 includes a plurality of adjacent (contacting) tiles 602a, 602b. Each tile 602a, 602b includes an LED array 610. Each LED array 610 includes a plurality of LEDs 612 arranged in a sparse distribution, similar to the LEDs described above. Each LED 612 can emit light of the same color, or can emit different lights of different colors. For convenience, electrical connections between the LEDs 612 and from the LEDs 612 to other (external) components (such as drivers) are not shown. Multiple LEDs 612 of different colors can be arranged at each individual (pixel) position of the LED 612.

[0072] As shown, the panel 600 can be formed of adjacent LED arrays 610 (tiles 602a, 602b). In some embodiments, each LED array 610 can have the same size and can have the same number of LEDs 612. The LEDs 612 within each LED array 610 can be separated by a uniform or substantially uniform distance D in two orthogonal (xy) directions. Each LED 612 closest to the edge in each LED array 610 is arranged to be arranged at a uniform distance D / 2 halfway from the edge of the LED array 610.

[0073] Although LED 612 Figure 6 602a, 602b. The LED arrays 610 are shown as being arranged in a square LED array 610 (i.e., the number of LEDs 612 is the same in each orthogonal direction), but any shape of LED array (e.g., rectangular, triangular) can be used in the panel 600, as long as the LED arrays can be assembled together so as to contact another LED array on all sides and the spacing between the LEDs 612 remains constant. Drivers and other control circuits can be arranged at one electronic device edge 620 of each tile 602a, 602b or at the opposite edge. The electronic device edge 620 can be orthogonal to the common edge between the tiles 602a, 602b. The electronic device edge 620 can include multiple drivers, each of which is configured to drive one or more micro LEDs in each pixel.

[0074] Thus, the display formed by the panel 600 may be substantially edgeless. That is, at most three sides may be free of any visible power conductors or signal buses. Such a display may be formed by a plurality of tiles 602a, 602b having substantially the same characteristics and substantially uniform distances between pixels (LEDs) to form a larger display.

[0075] Although not shown, in some embodiments, each panel or tile may include one or more control components. The control component may include one or more sensors to detect users near the panel and / or tile and provide feedback to the processor. In addition, the panel or tile may include other sensors (such as touch sensors) to allow the panel or tile to be used as a user input device in addition to simply displaying information. In this case, the panel or tile may, for example, use a panel or tile on a side window containing a sparse LED array to display an alphanumeric board (the display may be activated based on a proximity sensor in the panel that detects the presence of a user). The panel or tile may also include one or more connectors to an external digital signal, conductors and interfaces for powering the panel or tile, and other control circuits. For each nth pixel, an integrated circuit may be included that provides current to the LED of one or more pixels. In addition, in addition to conductors for power and digital signals, each pixel may include multiple LEDs of different colors (e.g., red, green, and blue LEDs) to enable a predetermined current to be transmitted to the LED.

[0076] Figure 7 An example of a panel with a single tile is shown. Panel 700 may include a single tile with a sparse LED array 702, an electronics edge 704, and a connector 706 electrically coupled to the electronics edge 704. The various components are described above. In the off mode, panel 700 is transparent. As described herein, panel 700 may provide a display on a single side or on opposite sides.

[0077] Figure 8A-8B An example of a panel with multiple display tiles is shown. Figure 7 , Fig. 8A and Figure 8B Each tile of the panels 800a, 800b in FIG. 8 may include a sparse LED array 802, an electronics edge 804, and a connector 806 electrically coupled to the electronics edge 804. Figure 8A-8B The rectangular tiles shown in Fig. 8A In , the electronic device edge 804 of the panel 800a can be arranged along a single continuous edge of the long edge of each tile forming the panel 800a (where the short edges are common between the rectangular tiles); Figure 8B In the closed mode, the electronic device edge 804 of the panel 800b can be arranged along the opposite edge of the short edge of each tile forming the panel 800b (where the long edge is common between the rectangular tiles). In the closed mode, the panel 800b is transparent. The panel 800b can provide a display on a single side or on opposite sides. Fig. 8A and Figure 8BIn one embodiment, the tiles are the same size; in other embodiments, the tiles can be different sizes as long as the distance between pixels (which contain multiple LEDs of different colors) is the same.

[0078] Fig. 9A and Fig. 9B An example of a sparse LED array arrangement is shown. As described herein, a double-sided panel 900a, 900b (e.g., a double-sided display) can include a panel 914 that includes a plurality of sparse LED arrays 912a, 912b arranged back to back. Individual (or sets of pixels) in the sparse LED arrays 912a, 912b. Each of the sparse LED arrays 912a, 912b can be disposed on an opaque substrate, thereby limiting viewing of information projected to only one hemisphere. A connection 918, such as a cable or wiring, can provide power and enable control by a processor of the panel 914 via traces 916, which are connected to the electronics of the panel 914 that control the sparse LED arrays 912a, 912b. As Fig. 9A As shown in , panel 914 can be disposed within a cavity formed by transparent material 910. One end of power connection 918 can be retained within transparent material 910 to provide a secure electrical connection to trace 916. Fig. 9B As shown in , the panel 914 may instead be disposed on the transparent material 910 and protected by a protective layer 920 (such as PET). Fig. 9A and Fig. 9B The use of a double-sided sparse LED array arrangement as described in can allow different information to be displayed to an observer on opposite sides of the transparent material 910 without restricting viewing through the transparent material 910 in either direction.

[0079] Fig.10 An example display is shown. Display 1000 may include a display stack 1002 including, for example, Figure 6 The sparse array in the panel shown in Figure 5C or Figure 5D The display stack 1002 may thus include LEDs (such as micro-LEDs) that emit substantially equivalently from both sides of the display 1000, as shown by Figure 5C or Figure 5D The transparent contacts and regions on both the n-side and p-side of the structure are provided. In addition, the backplane ( Fig.10The substrate (not shown) can be substantially transparent, including the primary area of ​​emission (the area of ​​the LED array) and most of the conductive traces that provide power and control to the LEDs of the array (and other components of the panel). Thus, the substrate can be formed of one or more materials (such as glass, PET, polyamideimide, polyetherimide, or transparent polyimide), and the conductive traces can be formed of one or more TCO materials (such as ITO). The interconnect or bonding system for the LEDs to the backplane can also be substantially transparent.

[0080] In some embodiments, the display stack 1002 may include LEDs, a backplane (traces, power input, substrate) controls / processors, etc. In some embodiments, the display stack 1002 may have a front side on which the micro-LEDs are disposed and a back side that forms a backplane. In some embodiments, the display stack 1002 may include LEDs, a backplane (traces, power input, substrate) controls / processors, etc. In some embodiments, the display stack 1002 may have a front side on which the micro-LEDs are disposed and a back side that forms a backplane.

[0081] The darkening layers 1004a, 1004b may be disposed on the outermost sides of each side of the display stack 1002. The darkening layers 1004a, 1004b may have various support structures; in some embodiments, the darkening layers 1004a, 1004b may be disposed on a substantially transparent contact (or on a transparent support layer), while in other embodiments, the darkening layers 1004a, 1004b may be separate from the panel as an independent layer on the display 1000 (and thus have an independent support structure). The darkening layers 1004a, 1004b may be selectively darkened (thereby providing selectable darkening) such that light is emitted from only one side of the display 1000. The darkening layers 1004a, 1004b may be formed of an electrochromic material, or may include an electrochromic material (thereby providing an electrochromic structure in the disclosed subject matter), which changes opacity in response to an electrical signal, thereby being able to provide, for example, electrochromic darkening. Electrochromic materials may also include a liquid crystal display (LCD) in which the polarization of the liquid crystals in the cell changes by 90° to block light from the display stack 1002 (which light may be polarized by a polarizing film on the LEDs and / or on the side of the darkening layers 1004a, 1004b opposite the display stack 1002). Activation of the darkening layers 1004a, 1004b on one side of the display 1000 may provide improved contrast for viewing light from the display stack 1002 on the opposite side of the display 1000 by blocking light generated by the LEDs in the display stack 1002 from exiting the dual-sided display (or the panels forming the display stack 1002) on one side of the display 1000. In some embodiments, the darkening layers 1004a, 1004b may be provided using an iris or other mechanically activated layer rather than using an electrochromic material.

[0082] The darkening layers 1004a, 1004b may have a transparent mode, in which the darkening layers 1004a, 1004b are transparent and thus transmit light from the display stack 1002, and an opaque mode, in which the darkening layers 1004a, 1004b are opaque and thus block light from the display stack 1002. The darkening layers 1004a, 1004b may be disposed on only one side of the display stack 1002, or on both sides of the display stack 1002. Each darkening layer 1004a, 1004b may be independently activatable, such that none, one, or both of the darkening layers 1004a, 1004b may be activated (opaque) or deactivated (transparent). The darkening layers 1004a, 1004b may be controlled by a processor. The processor may be part of the panel or display 1000, or may be within a system of which the display 1000 is a part. In some embodiments, the entire area of ​​the darkening layer 1004a, 1004b can be controlled by the processor as a single element, that is, the entire darkening layer 1004a, 1004b can have the same state (transparent, opaque or intermediate state). In other embodiments, the darkening layer 1004a, 1004b can be divided into multiple areas, and these areas are controlled separately by the processor.

[0083] In some embodiments, the darkening layers 1004a, 1004b may be controlled in response to sensor information. One or more sensors may provide sensor information to the processor. Like the darkening layers 1004a, 1004b, the sensors may be integrated into the panel or display 1000, or may be within a system of which the display 1000 is a part.

[0084] The sensor may include a proximity sensor and / or a (capacitive) touch sensor. The proximity sensor and the touch sensor may implement presence detection and use detection, respectively, to provide a user experience. The proximity sensor may sense which side of the display 1000 the user is on, and orient the displayed image correctly. The proximity sensor may use infrared light to determine the presence of the user on one side of the display 1000. The processor may determine that the user is present for a predetermined amount of time (e.g., greater than about 5 seconds), and activate the darkening layers 1004a, 1004b on the other side of the display 1000 from the user. Alternatively, the proximity sensor may include a camera, and the processor may determine that the user is present based on facial recognition of an image captured by the camera.

[0085] In general, each pixel in the display 1000 can emit light in directions symmetrical about a normal direction that is orthogonal to the underlying portion on which the pixel is disposed. For example, in some embodiments, light from each pixel can be radiated in a Lambertian pattern. However, the propagation of light in the normal direction may result in reduced viewing ability for individuals not within the main lobe of the Lambertian pattern because a significant portion of the light is directed toward an unviewable direction. To this end, in some embodiments, one or more optical elements in a sparse array can be used to adjust the emission angle to an optimized direction in which the (Lambertian) pattern of the emitted light is centered at a main non-perpendicular viewing angle based on a viewing position of a detected user position. Similar to augmented reality / virtual reality systems, eye tracking information can also be used to adjust the light emission angle.

[0086] Alternatively, in other embodiments, Fig. 9A or Fig. 9B The double-sided array shown in Figure 5C or Figure 5D The LEDs shown in the figure can be used Fig.10 In this case, since the arrays can be independently controlled and thus can show the same information or different information, the darkened layers 1004a, 1004b may or may not be present.

[0087] Fig.11 An example system is shown. System 1100 may include one or more light sources 1110a, 1110b. The first light source 1110a may include one or more of a sparse LED array 1112, as described herein. The first light source 1110a may include a local driver 1114, also as described herein. The first light source 1110a may be disposed in various locations on or within a device, as described in more detail herein. A second light source 1110b may be present and may include one or more non-sparse LED arrays 1116 (e.g., micro-LED arrays, mini-LED arrays, etc.). The second light source 1110b may be disposed in various other locations on or within a device containing system 1100.

[0088] The LEDs in the first light source 1110a and / or the second light source 1110b may include micro-LEDs. The micro-LED array contains thousands to millions of tiny micro-LEDs that emit light and can be controlled individually or in groups of pixels (e.g., 5×5 pixel groups). The micro-LEDs are small (e.g., side length <0.07 mm) and can use inorganic semiconductor materials (such as those described above) to provide monochromatic or multi-color light, typically red, green, blue, or yellow. Other LEDs may have, for example, approximately 4 mm 2, 250 microns by 250 microns or larger in size. MicroLEDs can be used similarly to thin film LEDs because they are approximately 5 μm thick, and because they have no inherent substrate, they can be placed directly on a backplane. This results in the overall thickness of the light source being significantly less than that of other LEDs, and allows the use of microLEDs in the structures described herein. The individual control provided by the microLEDs allows the drive electronics for the display to use an active matrix array of drive transistors or a full driver micro IC for individual intensity control. The use of micro ICs can be used to provide a considerable amount of fine control over the operation of each LED.

[0089] The controller 1130 may include a processor 1132, which may be used to control various functions of the system 1100. As also shown, the controller 1130 may include additional components, such as a driver 1134, which is configured to, among other things, drive the second light source 1110b controlled by the processor 1132. In some embodiments, the driver 1134 may also be configured to provide non-local driving of the sparse LED array 1112 of the first light source 1110a.

[0090] As described above, the LEDs in the sparse LED array 1112 and the non-sparse LED array 1116 can be formed from one or more inorganic materials (e.g., binary compounds such as gallium arsenide (GaAs), ternary compounds such as aluminum gallium arsenide (AlGaAs), quaternary compounds such as indium gallium phosphide (InGaAsP), gallium nitride (GaN), or other suitable materials), typically group III-V materials (defined by the columns of the periodic table) or group II-VI materials. The LEDs in different arrays can emit light in the visible spectrum (about 400nm to about 800nm) and / or can emit light in the infrared spectrum (above about 800nm). At least some of the LEDs can be formed by combining n-type and p-type semiconductors on a rigid substrate (which can be textured), the rigid substrate being, for example, sapphire aluminum oxide (AlO), among others. 2 O 3 ) or silicon carbide (SiC). In particular, during the manufacture of LEDs, various layers are deposited and processed on a substrate. Before depositing the various layers, the surface of the substrate may be pre-treated to anneal, etch, polish, etc. the surface. The original substrate may be removed and replaced by a thin transparent rigid substrate (such as glass) or a flexible substrate (e.g., plastic).

[0091] In general, epitaxial semiconductor deposition (e.g., by metal organic chemical vapor deposition) can be used to deposit one or more semiconductor layers, metal deposition (e.g., by sputtering), oxide growth, and other operations such as etching, stripping, and cleaning to manufacture various LED layers. The substrate can be removed from the LED structure after manufacturing and after being connected to contacts on the backplane via metal bonding (such as via wires or ball soldering). The backplane can be a printed circuit board or a wafer containing an integrated circuit (IC), such as a complementary metal oxide semiconductor (CMOS) IC wafer. Semiconductor deposition operations can be used to create an LED with an active region in which electron-hole recombination occurs and light from the LED is generated. The active region can be, for example, one or more quantum wells. Metal contacts can be used to provide drive current to n-type and p-type semiconductors from an IC (such as a driver) of the backplane on which the LED is disposed. Methods of depositing materials, layers and films may include, for example, sputtering deposition, atomic layer deposition (ALD), chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma enhanced atomic layer deposition (PEALD), plasma enhanced chemical vapor deposition (PECVD), and combinations thereof, among others.

[0092] In some embodiments, one or more other layers (such as a phosphor conversion layer containing phosphor particles) can be disposed on some or all of the LEDs or some or all of the LED arrays 1112, 1116 to convert at least a portion of the light from the LEDs to light of a different wavelength. For example, blue light from a GaN LED can be converted by a phosphor conversion layer into near infrared light or white light.

[0093] The light sources 1110a, 1110b may include at least one lens and / or other optical elements, such as a reflector. In different embodiments, a single lens may be disposed over one or more of the LED arrays 1112, 1116, multiple lenses may be disposed over one or more of the LED arrays 1112, 1116, wherein a single lens is disposed over one or more of the LED arrays 1112, 1116, or multiple lenses may be disposed over one or more of the LED arrays 1112, 1116, wherein a single lens is disposed over one or more LEDs in each of the LED arrays 1112, 1116. The at least one lens and / or other optical element may direct light emitted by one or more of the LED arrays 1112, 1116 toward a target.

[0094] The processor 1132 may also control a sensor 1120 including a multi-pixel detector 1122. The sensor 1120 may sense light at one or more wavelengths emitted by the second LED array 1116 and reflected by the target and / or radiation emitted by the target. The sensor 1120 may be, for example, a radar or lidar sensor, or the processor 1132 may be used to determine the presence of a specific object nearby (e.g., other vehicles, people, road signs). The sensor 1120 may include an optical element (e.g., at least one sensor lens) to capture the radiation. The multi-pixel detector 1122 may include, for example, a photodiode or one or more other detectors capable of detecting light within the wavelength range(s) of interest.

[0095] The multi-pixel detector 1122 may include multiple different arrays to sense visible light and / or infrared light. Similar to the LED array 1116, the multi-pixel detector 1122 may have one or more segments (which can sense the same wavelength / wavelength range or different wavelengths / wavelength ranges).

[0096] In some embodiments, instead of or in addition to providing a multi-pixel detector in the sensor 1120, a multi-pixel detector may be provided in the second light source 1110b. In some embodiments, the second light source 1110b and the sensor 1120 may be integrated into a single module, while in other embodiments, the second light source 1110b and the sensor 1120 may be separate modules disposed on a printed circuit board (PCB) or other base. In other embodiments, the second light source 1110b and the sensor 1120 may be attached to different PCBs or bases.

[0097] The LEDs in each of the LED arrays 1112, 1116 can be driven in an analog or digital manner, i.e., using a direct current (DC) driver or pulse width modulation (PWM). As shown, drivers 1114, 1134 can be used to drive the LEDs in the LED arrays 1112, 1116, respectively, as well as other components (such as actuators).

[0098] A power source 1140 (such as a battery) may be used to Fig.10 The components of the system 1100 shown in FIG. 1 are powered.

[0099] The first light source 1110a can be arranged to emit light in a sparse distribution so that the LEDs occupy a small surface density to enable visual observation of the information provided by the first light source 1110a while allowing viewing through the underlying transparent (flexible) substrate of the area between the LEDs along a line of sight through the area between the LEDs. This can allow an observer on the emission side of the first light source 1110a to view the information projected by the first light source 1110a as well as the underlying scene. In other embodiments where the underlying substrate fully reflects visible light or specularly reflects, the area between the LEDs may not be viewable.

[0100] The information projected by the first light source 1110a can be static or moving, similar to the information that can be formed by a non-sparse light source. The LEDs of the first light source 1110a can be electrically connected using conductive traces on the substrate, which are configured to provide a drive current to the LEDs from the driver 1114. As described above, the conductive traces can be transparent and include one or more layers of TCO. The conductive traces can be relatively narrow even if formed of opaque metal and spaced far enough apart to allow visual observation through the substrate without substantial interference. The conductive traces can be, for example, less than about 110 μm wide. The LEDs can be connected in series or in parallel to one or more edges containing a control circuit (and a power supply) via conductive traces along each row and column, and can be addressed individually or in groups of LEDs. The driver 1114 and other control devices in the first light source 1110a for each pixel can also be referred to as a micro IC.

[0101] Fig.12 An example of a common device according to some embodiments is shown. Device 1200 may be, for example, a vehicle embedded display. Various elements may be provided on the backplane described above, while other elements may be local or remote. As described herein, an example may include or may operate on a logic or a number of components, modules, or mechanisms.

[0102] Modules and components are tangible entities (e.g., hardware) that can perform specified operations and can be configured or arranged in a certain manner. In one example, circuits can be arranged as modules in a specified manner (e.g., internally or relative to external entities such as other circuits). In one example, all or part of one or more computer systems (e.g., independent, client or server computer systems) or one or more hardware processors can be configured by firmware or software (e.g., instructions, application parts, or applications) as modules for performing specified operations. In one example, the software can reside on a machine-readable medium. In one example, the software, when executed by the underlying hardware of the module, causes the hardware to perform the specified operation.

[0103] Thus, the term "module" (and "component") should be understood to encompass a tangible entity, i.e., a physically constructed, specially configured (e.g., hardwired), or temporarily (e.g., temporarily) configured (e.g., programmed) entity that operates in a specified manner or performs part or all of any of the operations described herein. Considering an example where a module is temporarily configured, each module need not be instantiated at any one time. For example, where a module includes a general-purpose hardware processor configured using software, the general-purpose hardware processor can be configured into corresponding different modules at different times. The software can configure the hardware processor accordingly, for example, to constitute a particular module at one time and to constitute different modules at different times.

[0104] The electronic device 1200 may include a hardware processor (or equivalent processing circuit) 1202 (e.g., a central processing unit (CPU), a GPU, a hardware processor core, or any combination thereof), a memory 1204 (which may include main memory and static memory), some or all of which may communicate with each other via an interconnect (e.g., a bus) 1208. The memory 1204 may include any or all of removable storage and non-removable storage, volatile memory, or non-volatile memory. The electronic device 1200 may further include a display / light source 1210 (such as the above-mentioned LED or video display), an alphanumeric input device 1212 (e.g., a keyboard), and a user interface (UI) navigation device 1214 (e.g., a mouse). In one example, the display / light source 1210, the input device 1212, and the UI navigation device 1214 may be a touch screen display. The electronic device 1200 may additionally include a storage device (e.g., a drive unit) 1216, a signal generating device 1218 (e.g., a speaker), a network interface device 1220, one or more cameras 1228, and one or more sensors 1230 (such as a global positioning system (GPS) sensor, a compass, an accelerometer, or other sensors such as those described herein). The electronic device 1200 may further include an output controller, such as a serial connection (e.g., a universal serial bus (USB)), a parallel connection, or other wired or wireless connection (e.g., infrared (IR), near field communication (NFC), etc.) to communicate or control one or more peripheral devices (e.g., a printer, a card reader, etc.). Some elements (such as one or more sparse arrays providing a display / light source 1210) may be remote from other elements and may be controlled by the hardware processor 1202.

[0105] The storage device 1216 may include a non-transitory machine-readable medium 1222 (hereinafter referred to as a machine-readable medium) on which one or more sets of data structures or instructions 1224 (e.g., software) are stored, which embody or are used by any one or more of the techniques or functions described herein. The instructions 1224 may also reside completely or at least partially within the memory 1204 and / or within the hardware processor 1202 during execution of its instructions 1224 by the electronic device 1200. Although the machine-readable medium 1222 is shown as a single medium, the term "machine-readable medium" may include a single medium or multiple media (e.g., a centralized or distributed database, and / or associated caches and servers) configured to store one or more instructions 1224.

[0106] The term "machine-readable medium" may include any medium capable of storing, encoding, or carrying instructions for execution by the electronic device 1200 and causing the electronic device 1200 to perform any one or more of the techniques of the present disclosure; or any medium capable of storing, encoding, or carrying data structures used by or associated with such instructions. Non-limiting examples of machine-readable media may include solid-state memory and optical and magnetic media. Specific examples of machine-readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM)) and flash memory devices; magnetic disks, such as built-in hard disks and removable disks; magneto-optical disks; random access memory (RAM); and CD-ROM and DVD-ROM disks.

[0107] Instructions 1224 can further be transmitted or received via a communication network using a transmission medium 1226 via a network interface device 1220 using any of several wireless local area network (WLAN) transmission protocols or SPI or CAN bus. Example communication networks may include local area networks (LANs), wide area networks (WANs), packet data networks (e.g., the Internet), mobile phone networks (e.g., cellular networks), plain old telephone (POTS) networks, and wireless data networks. The communication over the network may include one or more different protocols, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 family of standards known as Wi-Fi, the IEEE 802.14 family of standards known as WiMax, the IEEE 802.14.4 family of standards, the long-term evolution (LTE) family of standards, the universal mobile telecommunications system (UMTS) family of standards, peer-to-peer (P2P) networks, next generation (NG) / sixth generation (6G) standards, and the like. In one example, the network interface device 1220 may include one or more physical jacks (e.g., Ethernet jacks, coaxial jacks, or telephone jacks) or one or more antennas to connect to the transmission medium 1226.

[0108] Note that the term "circuit" as used herein refers to, is part of, or includes a hardware component, such as an electronic circuit, a logic circuit, a processor (shared, dedicated, or group) and / or a memory (shared, dedicated, or group), an application specific integrated circuit (ASIC), a field programmable device (FPD) (e.g., a field programmable gate array (FPGA), a programmable logic device (PLD), a complex PLD (CPLD), a high capacity PLD (HCPLD), a structured ASIC, or a programmable SoC), a digital signal processor (DSP), etc., which is configured to provide the described functions. In some embodiments, the circuit can execute one or more software or firmware programs to provide at least some of the described functions. The term "circuit" may also refer to a combination of one or more hardware elements and a program code for performing the functions of the program code (or a combination of a circuit used in an electrical or electronic system and a program code for performing the functions of the program code). In these embodiments, the combination of hardware elements and program code may be referred to as a specific type of circuit.

[0109] As used herein, the term "processor circuit" or "processor" therefore refers to, is part of, or includes a circuit that is capable of sequentially and automatically performing a series of arithmetic or logical operations or recording, storing, and / or transmitting digital data. The term "processor circuit" or "processor" may refer to one or more application processors, one or more baseband processors, a physical central processing unit (CPU), a single-core or multi-core processor, and / or any other device capable of executing or otherwise operating computer-executable instructions (such as program code, software modules, and / or functional processes).

[0110] The camera 1228 can sense at least one or more wavelengths of light emitted by the LED. The camera 1228 can include an optical element (e.g., at least one camera lens) that can collect reflected light from the illumination area and / or the illumination emitted by the illumination area. The camera lens can direct the reflected light onto a multi-pixel sensor (also referred to as a light sensor) to form an image on the multi-pixel sensor.

[0111] The processor 1202 can control and drive the LEDs via one or more drivers. For example, the processor 1202 can optionally control one or more LEDs in the LED array independently of one or more LEDs in the LED array to illuminate an area in a specified manner.

[0112] Additionally, sensor 1230 may be incorporated into camera 1228 and / or light source 1210. Sensor 1230 may sense visible light and / or infrared light, and in addition to receiving reflected light from the LEDs, may further sense ambient light and / or changes / flickering in ambient light. Similar to an LED array, a sensor may have one or more segments (which may be capable of sensing the same wavelength / range of wavelengths or different wavelengths / ranges of wavelengths).

[0113] Figure 13A-13G An example of a process 1300 for fabricating a sparse array is shown in accordance with some embodiments. Fig.14 Shown according to Figure 13A-13G The process operations shown in FIG. 1400 are examples of methods for manufacturing sparse arrays. Figure 13A-13G and Fig.14 , the process Fig.13A Start with the transparent flexible sheet 1302 in the Fig.14 In operation 1402, the transparent flexible sheet 1302 can be attached to a carrier wafer 1304 (or other type of carrier substrate), such as Fig. 13B At operation 1404, metal traces 1306 may be deposited on transparent flexible sheet 1302, such as Fig. 13C At operation 1406, LED array 1308 may be assembled on metal trace 1306, as shown in FIG. Fig.13D At operation 1408, the transparent flexible sheet 1302 including the metal traces 1306 and the LED array 1308 can be released from the carrier wafer 1304, as shown in FIG. Fig.13E At operation 1410, adhesive layer 1310 may be laminated on transparent flexible sheet 1302 to cover metal traces 1306 and LED array 1308, as shown in FIG. Fig.13F At operation 1412, the transparent flexible sheet 1302 may be flipped over and laminated onto the printed circuit board 1312, as shown in FIG. Figure 13G as shown in .

[0114] In other embodiments, a backplane with traces can be formed on a transparent substrate. A sparse LED array (which may include microLEDs) can be transferred to a transparent substrate with a backplane. For example, a mass transfer process can be used to perform the transfer to provide a sparse LED array. For example, mass transfer can be used to deposit microLED (and microIC) masses on a transparent substrate by selecting a location with a stamp and tying or fixing the transferred material with an adhesive layer. In another example, the transfer can be performed using one or more printing nozzles arranged in parallel to provide a sparse LED array in a vacuum nozzle transfer process. The printing nozzle can be an ENJET tool suitable for the process. A laminated structure can then be formed in either case. In other embodiments, after the transfer, the ENJET tool can be used to repair or replace a specific microLED.

[0115] Alternatively, the traces may be formed on a transparent substrate.The LEDs may then be formed on the transparent substrate and a laminate structure formed as described above.

[0116] Fig.15 An example of a process for providing improved contrast according to some embodiments is shown. During process 1500, the presence of a user on one side of a sparse display is determined in operation 1502. For example, a proximity detector can be used to detect the presence of a user. In operation 1504, one of the darkening layers disposed on both sides of the display is activated to darken that side of the display. Specifically, the darkening layer on the side of the display opposite to the detected user is activated to eliminate light transmitted through the display from the side of the display opposite to the detected user and improve the image contrast for the user. In various embodiments herein, when contrast is desired, a darkening layer, rather than an opaque layer, can replace a mirror that controllably reflects light from an LED back toward the user. In this case, an optical element at the darkening layer can be used to adjust the reflected light to mimic light emitted directly toward the user from the LED.

[0117] Fig.16An example display stack according to various embodiments of the disclosed subject matter is shown. The display stack 1600 may include several layers, such as those described above. As shown, the darkening layer 1602a, 1602b may be the outermost layer of the display stack 1600. The darkening layer 1602a, 1602b may include, among other things, an electrochromic material, an LCD, or an electronic ink. The thickness of the darkening layer 1602a, 1602b may range from about 15 μm to about 500 μm, typically about 50 μm. The darkening layer 1602a, 1602b may be attached to the transparent substrate 1606a, 1606b using a transparent adhesive 1604a, 1604b. The transparent adhesive 1604a, 1604b may include, among other things, silicone, siloxane, epoxy-silicone mixture, epoxy, or acrylic resin. The thickness of the transparent adhesive 1604a, 1604b can range from about 2 μm to about 100 μm, typically about 10 μm. The transparent substrates 1606a, 1606b can include glass, PET, or transparent PI, among others. The thickness of the transparent substrates 1606a, 1606b can range from about 50 μm to about 1000 μm, typically about 100 μm. One of the transparent substrates 1606a, 1606b can be a dummy backplane for mechanical support.

[0118] The micro-LEDs 1610 may be embedded in a conformal transparent adhesive 1608. The conformal transparent adhesive 1608 may include, among other things, silicone, siloxane, epoxy-silicone mixture, epoxy, or acrylic. The thickness of the conformal transparent adhesive 1608 may range from about 10 μm to about 100 μm, typically about 25 μm. The micro-LEDs 1610 may include GaN, InGaN, AlInGaP, GaAs, or InGaAs (i.e., light emitting semiconductors). The thickness of the micro-LEDs 1610 may range from about 3 μm to about 15 μm, typically about 5 μm.

[0119] Micro-LEDs 1610 may be attached to transparent oxide conductors 1614 via interconnect metal 1612. Interconnect metal 1612 may include Au, Sn, AuSn, In, ACF / ACInk, or SAC, among others. The thickness of interconnect metal 1612 may range from about 0.02 μm to about 5 μm, typically about 0.1 μm. Transparent oxide conductor 1614 may include ITO, ZnO, or SnO, among others. The thickness of transparent oxide conductor 1614 may range from about 0.5 μm to about 10 μm, typically about 1 μm.

[0120] The embodiments described herein may be used for video and signage displays that blend seamlessly with transparent surfaces. Other embodiments may include retail windows or glass information devices, and automotive windows including windshields. Although sparse arrays are discussed in detail herein, in other embodiments, having, for example, Figure 5C or Figure 5D The use of micro-LEDs of the structure described in can be used in a non-sparse array to provide a display similar to the above-mentioned display, such as Fig.10 as shown in .

[0121] Note that in various embodiments where the panel has multiple tiles, the electronics / controls (micro IC control circuitry on a thin transparent electrical backplane) can be on the same side, or can be on different sides of a single-sided display. The tiles of the panel can be capable of independent operation, and can provide multiple unrelated images, or can be aggregated to operate as controls for a single display.

[0122] In some cases (e.g., extreme miniaturization), the backplane may be formed of silicon CMOS, making the usability of the bidirectional display more limited. However, like the disclosed bidirectional display, even if the backplane is formed of silicon CMOS, such a display may be used as a display for a laptop and a tablet computer in a system such as in a laptop.

[0123] Example

[0124] Example 1 is a computer system comprising a double-sided display and a processor, wherein the processor is configured to control the double-sided display to provide light, wherein the computer system comprises a panel having at least one tile configured to display information, wherein the panel is disposed within a transparent material, wherein each of the at least one tile comprises a sparse array of micro light emitting diodes (micro LEDs), and wherein the processor is configured to control the micro LEDs to provide light for viewing on opposite sides of the panel.

[0125] In Example 2, the subject matter of Example 1 includes wherein in each tile of the panel, the array comprises: a transparent flexible substrate; a transparent rigid substrate adhered to the transparent flexible substrate via an adhesive layer, the array being encapsulated in the adhesive layer; and at least one driver disposed on an edge of the tile and configured to drive the LED.

[0126] In Example 3, the subject matter of Examples 1-2 includes wherein the panel further includes a darkening layer disposed on at least one side of the panel, and the processor is configured to control the darkening layer to provide selectable darkening to block light from leaving the dual-sided display on at least one side of the panel.

[0127] In Example 4, the subject matter of Example 3 includes, wherein the darkening layer includes at least one material selected from the group of materials consisting of an electrochromic material, a liquid crystal display (LCD), and electronic ink.

[0128] In Example 5, the subject matter of Examples 3-4 includes a proximity sensor configured to detect user presence on a side of the display, the processor configured to control the dimming layer to provide selectable dimming to a side of the display opposite the side of the display where the user presence is detected by the proximity sensor.

[0129] In Example 6, the subject matter of Example 5 includes, wherein the proximity sensor is integrated in the panel.

[0130] In Example 7, the subject matter of Examples 3-6 includes a touch sensor configured to receive user input on one side of the display, the processor configured to control the dimming layer to provide selectable dimming to a side of the display opposite to the side of the display where the user input is received by the touch sensor.

[0131] In Example 8, the subject matter of Example 7 includes, wherein the touch sensor is integrated in the panel.

[0132] In Example 9, the subject matter of Examples 1-8 includes, wherein the panel further includes: a first darkening layer disposed on a first side of the panel, the first darkening layer being configured to provide selectable darkening to block light from leaving the dual-sided display on the first side of the panel; and a second darkening layer disposed on a second side of the panel opposite to the first side of the panel, the second darkening layer being configured to provide selectable darkening to block light from leaving the dual-sided display on the second side of the panel, the first darkening layer and the second darkening layer being configured to be independently activatable between a transparent mode and an opaque mode.

[0133] In Example 10, the subject matter of Examples 1-9 includes, wherein the panel further includes a darkening layer disposed on at least one side of the panel, the processor is configured to control the darkening layer to provide selectable darkening to block light from leaving the dual-sided display on at least one side of the panel, and the darkening layer is configured to improve contrast for viewing light on a side of the dual-sided display that is not darkened by the darkening layer.

[0134] In Example 11, the subject matter of Examples 1-10 includes, wherein: the panel has a plurality of tiles, the control circuitry of each tile is disposed on a transparent electrical backplane of the tile, and the control circuitry of each tile is disposed on a single side of the display.

[0135] In Example 12, the subject matter of Examples 1-11 includes, wherein: the panel has a plurality of tiles, the control circuit of each tile is disposed on a transparent electrical backplane of the tile, and the control circuit of at least one tile is disposed on a different side of the display than the control circuit of at least one other tile.

[0136] In Example 13, the subject matter of Examples 1-12 includes, wherein: the panel has a plurality of tiles, and the processor controls the tiles to operate independently to provide unrelated images.

[0137] In Example 14, the subject matter of Examples 1-13 includes, wherein: the panel has a plurality of tiles, and the processor controls the tiles to provide a single extended display.

[0138] In Example 15, the subject matter of Examples 1-14 includes wherein the panel further includes a backplane formed of a silicon complementary metal oxide semiconductor (CMOS).

[0139] Example 16 is a computer system comprising: a double-sided display configured to emit light from opposite sides of the display; and a processor configured to control light from the double-sided display, the double-sided display having a panel comprising: a sparse array of micro light emitting diodes (micro LEDs) configured to emit light, and a darkening layer disposed on each side of the array, each darkening layer configured to independently switch between being transparent to light and being opaque to light, the processor configured to control the array and the darkening layer to display information to be selectively viewed on opposite sides of the panel.

[0140] In Example 17, the subject matter of Example 16 includes, wherein: the panel further includes a conformal transparent adhesive, a transparent backplane, and a transparent substrate, the array is disposed in the conformal transparent adhesive between the transparent backplane and the transparent substrate, and the darkening layer is disposed on surfaces of the transparent backplane and the transparent substrate opposite to the array.

[0141] In Example 18, the subject matter of Examples 16-17 includes a proximity sensor configured to detect user presence on a side of a display, the processor configured to control one of the darkening layers to switch from transparent to opaque in response to detecting the user presence, one of the darkening layers being on a side of the display opposite to the side of the display where the user presence is detected.

[0142] In Example 19, the subject matter of Examples 16-18 includes a touch sensor configured to receive user input on a side of a display, and a processor configured to control one of the darkening layers to switch from transparent to opaque in response to receipt of the user input, and one of the darkening layers is on a side of the display opposite to the side of the display receiving the user input.

[0143] Example 20 is a computer system comprising: a double-sided display configured to emit light from opposite sides of the display; and a processor configured to control light from the double-sided display, the double-sided display having a panel comprising: an array of light emitting diodes (LEDs) configured to emit light; and a darkening layer disposed on each side of the array, each darkening layer configured to independently switch between being transparent to light and being opaque or reflective to light, the processor configured to control the array and the darkening layer to display information to be selectively viewed on opposite sides of the panel.

[0144] In Example 21, the subject matter of Example 20 includes, wherein: the panel has a plurality of tiles, and the processor controls the tiles to operate independently to selectively provide unrelated images or a single extended display.

[0145] Example 22 is at least one machine-readable medium comprising instructions that, when executed by a processing circuit, cause the processing circuit to perform operations to implement any of Examples 1-21.

[0146] Example 23 is a device including components implementing any of Examples 1-21.

[0147] Example 24 is a system implementing any of Examples 1-21.

[0148] Example 25 is a method of implementing any of Examples 1-21.

[0149] A panel is provided, comprising: a sparse array of micro light emitting diodes (micro LEDs) configured to emit light, and a darkening layer disposed on each side of the array, each darkening layer being configured to independently switch between being transparent to light and being opaque to light, and a processor being configured to control the array and the darkening layer to display information to be selectively viewed on opposite sides of the panel.

[0150] In Example 40, the subject matter of Example 39 includes, wherein: the panel further includes a conformal transparent adhesive, a transparent backplane, and a transparent substrate, the array is disposed in the conformal transparent adhesive between the transparent backplane and the transparent substrate, and the darkening layer is disposed on surfaces of the transparent backplane and the transparent substrate opposite to the array.

[0151] In Example 41, the subject matter of Examples 39-40 includes a proximity sensor configured to detect user presence on a side of the display, the processor configured to control one of the darkening layers to switch from transparent to opaque in response to detecting the user presence, and one of the darkening layers is on a side of the display opposite to the side of the display where the user presence is detected.

[0152] In Example 42, the subject matter of Examples 39-41 includes a touch sensor configured to receive user input on a side of the display, and the processor is configured to control one of the darkening layers to switch from transparent to opaque in response to receipt of the user input, and one of the darkening layers is on a side of the display opposite to the side of the display receiving the user input.

[0153] Example 43 is a computer system comprising: a double-sided display configured to emit light from opposite sides of the display; and a processor configured to control light from the double-sided display, the double-sided display having a panel comprising: an array of light emitting diodes (LEDs) configured to emit light; and a darkening layer disposed on each side of the array, each darkening layer configured to independently switch between being transparent to light and being opaque or reflective to light, the processor configured to control the array and the darkening layer to display information to be selectively viewed on opposite sides of the panel.

[0154] In Example 44, the subject matter of Example 43 includes, wherein: the panel has a plurality of tiles, and the processor controls the tiles to operate independently to selectively provide unrelated images or a single extended display.

[0155] Example 45 is at least one machine-readable medium comprising instructions that, when executed by a processing circuit, cause the processing circuit to perform operations to implement any of Examples 1-44.

[0156] Example 46 is a device including components implementing any of Examples 1-44.

[0157] Example 47 is a system implementing any of Examples 1-44.

[0158] Example 48 is a method of implementing any of Examples 1-44.

[0159] In some embodiments, other components may exist, while in other embodiments, not all components may exist. As indicated herein, although the term "one" is used herein, one or more associated elements may be used in different embodiments. For example, the term "processor" configured to perform a specific operation includes both a single processor configured to perform all operations and a plurality of processors individually configured to perform some or all operations (which may overlap) so that the combination of processors performs all operations. In addition, the term "comprising" may be considered to be interpreted as "at least comprising" the following elements.

[0160] Although only certain features of the system and method have been illustrated and described herein, many modifications and changes will be made by those skilled in the art. Therefore, it should be understood that the appended claims are intended to cover all such modifications and changes. The method operations may be performed substantially simultaneously or in different orders.

Claims

1. A computer system comprising a double-sided display and a processor configured to control the double-sided display to provide light, the computer system comprising a panel having at least one tile configured to display information, the panel being disposed within a transparent material, each of the at least one tile comprising a sparse array of micro light emitting diodes (micro LEDs), the processor being configured to control the micro LEDs to provide light for viewing on opposite sides of the panel.

2. The computer system of claim 1 , wherein in each tile of the panel, the array comprises: A substantially transparent flexible substrate; a substantially transparent rigid substrate adhered to a transparent flexible substrate via an adhesive layer, the array being encapsulated in the adhesive layer; and At least one driver is disposed on an edge of the tile and is configured to drive the micro LEDs.

3. The computer system of claim 1 , wherein the panel further comprises a darkening layer disposed on at least one side of the panel, the processor being configured to control the darkening layer to provide selectable darkening to block light from leaving the dual-sided display on at least one side of the panel.

4. The computer system of claim 3, wherein the darkening layer comprises at least one material selected from the group consisting of an electrochromic material, a liquid crystal display (LCD), and electronic ink.

5. The computer system of claim 3 , further comprising a proximity sensor configured to detect user presence on one side of the display, the processor being configured to control the dimming layer to provide selectable dimming to a side of the display opposite to the side of the display where the user presence is detected by the proximity sensor. The computer system of claim 5 , wherein the proximity sensor is integrated into the panel.

7. The computer system of claim 3, further comprising a touch sensor configured to receive user input on one side of the display, the processor being configured to control the dimming layer to provide selectable dimming to a side of the display opposite to the side of the display on which the user input is received by the touch sensor.

8. The computer system of claim 7, wherein the touch sensor is integrated into the panel.

9. The computer system of claim 1, wherein the panel further comprises: a first darkening layer disposed on a first side of the panel, the first darkening layer configured to provide selectable darkening to block light from exiting the dual-sided display on the first side of the panel; and A second darkening layer is disposed on a second side of the panel opposite to the first side of the panel, the second darkening layer being configured to provide selectable darkening to block light from leaving the dual-sided display on the second side of the panel, the first darkening layer and the second darkening layer being configured to be independently activatable between a transparent mode and an opaque mode.

10. The computer system of claim 1 , wherein the panel further comprises a darkening layer disposed on at least one side of the panel, the processor being configured to control the darkening layer to provide selectable darkening to block light from leaving the dual-sided display on at least one side of the panel, the darkening layer being configured to improve contrast for viewing light on a side of the dual-sided display that is not darkened by the darkening layer.

11. The computer system of claim 1, wherein: The panel has a plurality of tiles, The control circuitry of each tile is located on the transparent electrical backplane of the tile, and The control circuitry for each tile is provided on a single side of the display.

12. The computer system of claim 1, wherein: The panel has a plurality of tiles, The control circuitry of each tile is placed on the transparent electrical backplane of the tile, and The control circuitry of at least one tile is disposed on a different side of the display than the control circuitry of at least one other tile.

13. The computer system of claim 1, wherein: The panel has a plurality of tiles, and The processor controls the tiles to operate independently to provide unrelated images.

14. The computer system of claim 1, wherein: The panel has a plurality of tiles, and The processor controls the tiles to provide a single extended display.

15. The computer system of claim 1, wherein the panel further comprises a backplane formed of silicon complementary metal oxide semiconductor (CMOS).

16. A computer system comprising: a dual-sided display configured to selectively emit light from opposite sides of the display; and a processor configured to control light from each of opposing sides of the dual-sided display, The double-sided display has a panel, and the panel includes: a sparse array of micro light emitting diodes (micro LEDs) configured to emit light; and A darkening layer is disposed on each side of the array, each darkening layer being configured to independently switch between being transparent to light and being opaque to light, and the processor is configured to control the array and the darkening layer to display information to be selectively viewed on opposite sides of the panel.

17. The computer system of claim 16, wherein: The panel further includes a conformal and substantially transparent adhesive, a substantially transparent backsheet, and a substantially transparent substrate; The array is disposed in a conformal transparent adhesive between a transparent backplane and a transparent substrate; as well as The darkening layer is disposed on the surface of the transparent back plate and the transparent substrate opposite to the array.

18. The computer system of claim 16, further comprising a proximity sensor configured to detect the presence of a user on one side of the display, the processor configured to control one of the darkening layers to switch from transparent to opaque in response to detecting the presence of the user, the one of the darkening layers being on a side of the display opposite to the side of the display where the presence of the user is detected.

19. The computer system of claim 16, further comprising a touch sensor configured to receive user input on one side of the display, the processor configured to control one of the darkening layers to switch from transparent to opaque in response to receipt of the user input, the one of the darkening layers being on a side of the display opposite to the side of the display receiving the user input.

20. A computer system comprising: a dual-sided display configured to selectively emit light from opposite sides of the display; and a processor configured to control light from the dual-sided display, The double-sided display has a panel, and the panel includes: an array of light emitting diodes (LEDs) configured to emit light; and A darkening layer is disposed on each side of the array, each darkening layer being configured to independently switch between being transparent to light and being opaque or reflective to light, and the processor is configured to control the array and the darkening layer to display information to be selectively viewed on opposite sides of the panel.

21. The computer system of claim 20, wherein: The panel has a plurality of tiles, and The processor controls the tiles to operate independently to selectively provide unrelated images or a single extended display.

Images