PATENT DOCUMENT

Publication Number: US-11822191-B2
Application Number: US-202016849164-A
Country: US
Kind Code: B2

Title: Display system with localized optical adjustments

Abstract:
An electronic device such as a head-mounted device may have a display that displays computer-generated content for a user. The head-mounted device may have an optical system that directs the computer-generated content towards eye boxes for viewing by a user. The optical system may include a spatially addressable adjustable optical component. The adjustable optical component may have first and second electrodes and an electrically adjustable material between the first and second electrodes. The electrically adjustable material may include a transparent conductive material such as indium tin oxide that includes a pattern of segmented trenches configured to provide the transparent conductive material with electrical anisotropy. Contacts may be coupled to the transparent conductive material. Control circuitry can adjust the electrically adjustable material to form a spatially addressable light modulator or adjustable lens.

Claims:
What is claimed is: 
     
       1. A spatially addressable adjustable optical component, comprising:
 a first electrode having a first sheet resistance along a first direction and a second sheet resistance that is more than the first sheet resistance along a second direction that is orthogonal to the first direction; 
 a second electrode having a third sheet resistance along the first direction and a fourth sheet resistance that is less than the third sheet resistance along the second direction; and 
 a layer of electrically adjustable optical material between the first and second electrodes, wherein an area of the layer of electrically adjustable optical material overlapping the first and second electrodes is configured to form a lens in response to a voltage applied across the area of the layer of electrically adjustable optical material using the first and second electrodes, and wherein a lens power of the lens is adjustable based on changes in the applied voltage to additional voltages. 
 
     
     
       2. The spatially addressable adjustable optical component defined in  claim 1  wherein the layer of electrically adjustable optical material comprises transparent liquid crystal material configured to exhibit changes in phase in light rays passing through the transparent liquid crystal material in response to changes in voltage across the layer of electrically adjustable optical material that are applied using the first and second electrodes. 
     
     
       3. The spatially addressable adjustable optical component defined in  claim 1  further comprising:
 a first set of contacts coupled to first and second opposing sides of the first electrode, wherein the first and second opposing sides are spaced apart along the first direction; and 
 a second set of contacts coupled to third and fourth opposing sides of the second electrode, wherein the third and fourth opposing sides are spaced apart along the second direction. 
 
     
     
       4. The spatially addressable adjustable optical component defined in  claim 1  wherein the first electrode comprises a transparent substrate coated with a transparent conductive coating that has segmented trenches running along the first direction. 
     
     
       5. The spatially addressable adjustable optical component defined in  claim 1  wherein the first electrode comprises a transparent substrate coated with a transparent conductive coating that has trenches with elongated portions oriented at an angle of 30-60° with respect to the first direction. 
     
     
       6. The spatially addressable adjustable optical component defined in  claim 5  wherein the trenches include trenches that are not straight. 
     
     
       7. A system, comprising:
 a head-mounted support structure; 
 a display device coupled to the head-mounted support structure that is configured to provide an image containing computer-generated content; and 
 an optical system that includes an optical coupler and an adjustable optical component and that provides the image using the optical coupler to an eye box while allowing a real-world object to be viewed through the adjustable optical component from the eye box, wherein the optical coupler is disposed between the adjustable optical component and the eye box, and wherein the adjustable optical component comprises:
 a first electrode formed from a first transparent conductive layer on a first transparent substrate, wherein the first transparent conductive layer contains openings patterned to provide the first transparent conductive layer with a first sheet resistance along a first direction and a second sheet resistance that is more than the first sheet resistance along a second direction that is different than the first direction; 
 a second electrode formed from a second transparent conductive layer on a second transparent substrate, wherein the second transparent conductive layer contains openings patterned to provide the second transparent conductive layer with a third sheet resistance along the first direction and a fourth sheet resistance that is less than the third sheet resistance along the second direction; and 
 a layer of electrically adjustable optical material between the first and second electrodes. 
 
 
     
     
       8. The system defined in  claim 7  wherein the first direction is perpendicular to the second direction and wherein the openings of the first and second transparent conductive layers comprise trenches having lengths less than 500 microns. 
     
     
       9. The system defined in  claim 8  wherein the trenches have widths of 0.5 microns to 20 microns. 
     
     
       10. The system defined in  claim 9  wherein the first and second transparent conductive layers comprise indium tin oxide. 
     
     
       11. The system defined in  claim 9  wherein the layer of electrically adjustable optical material comprises liquid crystal material, wherein the first electrode comprises a first set of metal contacts coupled to the first transparent conductive layer and the second electrode comprises a second set of metal contacts coupled to the second transparent conductive layer, and wherein the trenches have locally widened portions adjacent to the contacts.

Description:
This application claims the benefit of provisional patent application No. 62/860,721, filed Jun. 12, 2019, which is hereby incorporated by reference herein in its entirety. 
    
    
     BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with adjustable optical components. 
     Electronic devices sometimes include adjustable optical components. For example, wearable electronic devices such as head-mounted devices may include displays for displaying computer-generated content that is overlaid on real-world content. It may be desirable to place an adjustable optical component in line with a user&#39;s field of view. The adjustable optical component may be used, for example to adjust real-world object brightness as a user is viewing computer-generated content that is overlaid on top of real-world objects. 
     Challenges can arise when incorporating adjustable optical components into electronic devices. For example, adjustable optical components for head-mounted devices may be overly bulky or heavy. Some adjustable optical components have the potential to exhibit diffraction effects or other undesired effects that create visible artifacts. 
     SUMMARY 
     An electronic device such as a head-mounted device may have a display that displays computer-generated content for a user. The head-mounted device may have an optical system that directs the computer-generated image towards eye boxes for viewing by a user. 
     The optical system may include a spatially addressable adjustable optical component. The adjustable optical component may be configured to form a spatially addressable light modulator or adjustable lens. 
     The adjustable optical component may have first and second electrodes and an electrically adjustable material between the first and second electrodes. The electrically adjustable material may include a transparent conductive material such as indium tin oxide that includes a pattern of segmented trenches. The trenches may be configured to provide the transparent conductive material with electrical anisotropy, so that the sheet resistance of the transparent conductive material is different in different directions. This allows control circuitry to spatially control the voltage across the adjustable optical component. 
     The control circuitry may supply control signals to the adjustable optical component. Contacts may be coupled to the transparent conductive material. Control circuitry can adjust the electrically adjustable material by applying signals to the contacts during operation of the head-mounted device. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic diagram of an illustrative electronic device such as a head-mounted display device in accordance with an embodiment. 
         FIG.  2    is a top view of an illustrative head-mounted device in accordance with an embodiment. 
         FIG.  3    is a graph of visible light transmission versus applied drive signal for a light modulator such as a light modulator based on a guest-host liquid crystal device in accordance with an embodiment. 
         FIG.  4    is a cross-sectional side view of an illustrative spatially addressable adjustable optical component in accordance with an embodiment. 
         FIG.  5    is a top view of an illustrative electrode layer in a spatially addressable adjustable optical component in accordance with an embodiment. 
         FIG.  6    is a top view of another illustrative electrode layer in a spatially addressable adjustable optical component in accordance with an embodiment. 
         FIG.  7    is a top view of an illustrative spatially addressable adjustable optical component in accordance with an embodiment. 
         FIG.  8    is a top view of an illustrative layer with electrical anisotropy in accordance with an embodiment. 
         FIG.  9    is a top view of another illustrative layer with electrical anisotropy in accordance with an embodiment. 
         FIGS.  10  and  11    are top views of illustrative edge portions of layers in spatially addressable adjustable optical components in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices may include displays and other components for presenting content to users. The electronic devices may be wearable electronic devices. A wearable electronic device such as a head-mounted device may have head-mounted support structures that allow the head-mounted device to be worn on a user&#39;s head. 
     A head-mounted device may contain optical components such as a display for displaying visual content and a spatially addressable adjustable optical component such as a spatially addressable light modulator (sometimes referred to as a spatially addressable adjustable tint layer) or spatially addressable liquid crystal lens (sometimes referred to as an adjustable lens or spatially addressable adjustable lens). 
     Adjustable optical components may have a layer of electrically adjustable material such as a liquid crystal layer sandwiched between first and second electrode layers. By applying electric fields to selected contacts along the edges of the electrode layers, a desired electric field can be created through the layer of adjustable material in a location of interest. To reduce diffraction artifacts and other undesired visual artifacts that might arise from strips of electrode material, the electrode layers may be formed from transparent conductive layers that exhibit electrical anisotropy. 
     In some embodiments, a head-mounted device may include a lens system that includes an adjustable lens and/or fixed component(s) such as one or more fixed lenses. An adjustable lens system may be adjusted dynamically to accommodate different users and/or different operating situations. Adjustable light modulators may be used to selectively darken parts of a user&#39;s field of view. If, as an example, a head-mounted display system is being used to display computer-generated content that overlaps real-world objects, the brightness of the real-world objects can be selectively decreased to enhance the visibility of the computer-generated content. In particular, a spatially addressable adjustable light modulator may be used to generate a dark region that overlaps a bright real-world object that is overlapped by computer-generated content in the upper right corner of a user&#39;s field of view (as an example). 
     A schematic diagram of an illustrative system that may include adjustable optical components is shown in  FIG.  1   . As shown in  FIG.  1   , system  8  may include one or more electronic devices such as electronic device  10 . The electronic devices of system  8  may include computers, cellular telephones, head-mounted devices, wristwatch devices, and other electronic devices. Configurations in which electronic device  10  is a head-mounted device are sometimes described herein as an example. 
     As shown in  FIG.  1   , electronic devices such as electronic device  10  may have control circuitry  12 . Control circuitry  12  may include storage and processing circuitry for controlling the operation of device  10 . Circuitry  12  may include storage such as hard disk drive storage, nonvolatile memory (e.g., electrically-programmable-read-only memory configured to form a solid-state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in control circuitry  12  may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, graphics processing units, application specific integrated circuits, and other integrated circuits. Software code may be stored on storage in circuitry  12  and run on processing circuitry in circuitry  12  to implement control operations for device  10  (e.g., data gathering operations, operations involving the adjustment of the components of device  10  using control signals, etc.). Control circuitry  12  may include wired and wireless communications circuitry. For example, control circuitry  12  may include radio-frequency transceiver circuitry such as cellular telephone transceiver circuitry, wireless local area network (WiFi®) transceiver circuitry, millimeter wave transceiver circuitry, and/or other wireless communications circuitry. 
     During operation, the communications circuitry of the devices in system  8  (e.g., the communications circuitry of control circuitry  12  of device  10 ), may be used to support communication between the electronic devices. For example, one electronic device may transmit video and/or audio data to another electronic device in system  8 . Electronic devices in system  8  may use wired and/or wireless communications circuitry to communicate through one or more communications networks (e.g., the internet, local area networks, etc.). The communications circuitry may be used to allow data to be received by device  10  from external equipment (e.g., a tethered computer, a portable device such as a handheld device or laptop computer, online computing equipment such as a remote server or other remote computing equipment, or other electrical equipment) and/or to provide data to external equipment. 
     Device  10  may include input-output devices  22 . Input-output devices  22  may be used to allow a user to provide device  10  with user input. Input-output devices  22  may also be used to gather information on the environment in which device  10  is operating. Output components in devices  22  may allow device  10  to provide a user with output and may be used to communicate with external electrical equipment. 
     As shown in  FIG.  1   , input-output devices  22  may include one or more displays such as display(s)  14 . In some configurations, display  14  of device  10  includes left and right display devices (e.g., left and right components such as left and right scanning mirror display devices, liquid-crystal-on-silicon display devices, digital mirror devices, or other reflective display devices, left and right display panels based on light-emitting diode pixel arrays (e.g., organic light-emitting display panels or display devices based on pixel arrays formed from crystalline semiconductor light-emitting diode dies), liquid crystal display panels, and/or or other left and right display devices in alignment with the user&#39;s left and right eyes, respectively. In other configurations, display  14  includes a single display panel that extends across both eyes or uses other arrangements in which content is provided with a single pixel array. 
     Display  14  is used to display visual content for a user of device  10 . The content that is presented on display  14  may include virtual objects and other content that is provided to display  14  by control circuitry  12  and may sometimes be referred to as computer-generated content. Computer-generated content may be displayed in the absence of real-world content or may be combined with real-world content. In some configurations, a real-world image may be captured by a camera (e.g., a forward-facing camera) so that computer-generated content may be electronically overlaid on portions of the real-world image (e.g., when device  10  is a pair of virtual reality goggles with an opaque display). In other configurations, an optical coupling system may be used to allow computer-generated content to be optically overlaid on top of a real-world image. As an example, device  10  may have a see-through display system that provides a computer-generated image to a user through a beam splitter, prism, holographic coupler, or other optical coupler while allowing the user to view real-world objects through the optical coupler. 
     Input-output circuitry  22  may include sensors  16 . Sensors  16  may include, for example, three-dimensional sensors (e.g., three-dimensional image sensors such as structured light sensors that emit beams of light and that use two-dimensional digital image sensors to gather image data for three-dimensional images from light spots that are produced when a target is illuminated by the beams of light, binocular three-dimensional image sensors that gather three-dimensional images using two or more cameras in a binocular imaging arrangement, three-dimensional lidar (light detection and ranging) sensors, three-dimensional radio-frequency sensors, or other sensors that gather three-dimensional image data), cameras (e.g., infrared and/or visible digital image sensors), gaze tracking sensors (e.g., a gaze tracking system based on an image sensor and, if desired, a light source that emits one or more beams of light that are tracked using the image sensor after reflecting from a user&#39;s eyes), touch sensors, buttons, capacitive proximity sensors, light-based (optical) proximity sensors, other proximity sensors, force sensors, sensors such as contact sensors based on switches, gas sensors, pressure sensors, moisture sensors, magnetic sensors, audio sensors (microphones), ambient light sensors, microphones for gathering voice commands and other audio input, sensors that are configured to gather information on motion, position, and/or orientation (e.g., accelerometers, gyroscopes, compasses, and/or inertial measurement units that include all of these sensors or a subset of one or two of these sensors), and/or other sensors. 
     User input and other information may be gathered using sensors and other input devices in input-output devices  22 . If desired, input-output devices  22  may include other devices  24  such as haptic output devices (e.g., vibrating components), light-emitting diodes and other light sources, speakers such as ear speakers for producing audio output, and other electrical components. Devices  24  may include one or more adjustable optical components such as spatially addressable adjustable optical components formed from electrode layers with transparent conductive material exhibiting electrical anisotropy. Device  10  may include circuits for receiving wireless power, circuits for transmitting power wirelessly to other devices, batteries and other energy storage devices (e.g., capacitors), joysticks, buttons, and/or other components. 
     Electronic device  10  may have housing structures (e.g., housing walls, straps, etc.), as shown by illustrative support structures  26  of  FIG.  1   . In configurations in which electronic device  10  is a head-mounted device (e.g., a pair of glasses, goggles, a helmet, a hat, etc.), support structures  26  may include head-mounted support structures (e.g., a helmet housing, head straps, temples in a pair of eyeglasses, goggle housing structures, and/or other head-mounted structures). The head-mounted support structures may be configured to be worn on a head of a user during operation of device  10  and may support display(s)  14 , sensors  16 , other components  24 , other input-output devices  22 , and control circuitry  12 . 
       FIG.  2    is a top view of electronic device  10  in an illustrative configuration in which electronic device  10  is a head-mounted device. As shown in  FIG.  2   , electronic device  10  may include support structures (see, e.g., support structures  26  of  FIG.  1   ) that are used in housing the components of device  10  and mounting device  10  onto a user&#39;s head. These support structures may include, for example, structures that form housing walls and other structures for a main unit (e.g., support structures  26 - 2 ) and additional structures such as straps, temples, or other supplemental support structures (e.g., support structures  26 - 1 ) that help to hold the main unit and the components in the main unit on a user&#39;s face so that the user&#39;s eyes are located within eye boxes  60 . 
     Display  14  may include left and right display portions (e.g., sometimes referred to as left and right displays, left and right display devices, left and right display components, or left and right pixel arrays). An optical system for device  10  may be formed from couplers  84  (sometimes referred to as input couplers), waveguides  86 , optical couplers such as output couplers  88 , lenses  80  and/or  82 , and adjustable optical component(s)  94 . Adjustable optical components  94  of  FIG.  2    are shown as being interposed between the front face of device  10  and lenses  80 . In general, adjustable optical components  94  may be located at any suitable location in device  10  (e.g., any location among components such as lenses  80  output couplers  88 , and lenses  82 ). A user with eyes located in eye boxes  60  may view real-world objects through adjustable optical components  94  and other components of the optical system while viewing overlaid computer-generated content from display  14 . Adjustable optical components  94  may include adjustable light modulators and/or adjustable lenses. 
     As shown in  FIG.  2   , the left portion of display  14  may be used to create an image for a left-hand eye box  60  (e.g., a location where a left-hand image is viewed by a user&#39;s left eye). The right portion of display  14  may be used to create an image for a right-hand eye box  60  (e.g., a location where a right-hand image is viewed by a user&#39;s right eye). In the configuration of  FIG.  2   , the left and right portions of display  14  may be formed by respective left and right display devices (e.g., digital mirror devices, liquid-crystal-on-silicon devices, scanning microelectromechanical systems mirror devices, other reflective display devices, or other displays). In arrangements in which display  14  is opaque and blocks real-world images from direct viewing by the user, display  14  may be an organic light-emitting diode display, a liquid crystal display, or other display and the optical coupler formed from waveguides  86  and output couplers  88  may be omitted. 
     In the see-through display arrangement of  FIG.  2   , optical couplers  84  (e.g., prisms, holograms, etc.) may be used to couple respective left and right images from the left and right display portions into respective left and right waveguides  86 . The images may be guided within waveguides  86  in accordance with the principal of total internal reflection. In this way, the left and right images may be transported from the left and right sides of device  10  towards locations in the center of device  10  that are aligned with left and right eye boxes  60 . Waveguides  86  may be provided with respective left and right output couplers  88  such as holograms formed on or in the material of waveguides  86 . The left and right output couplers  88  may respectively couple the left and right images from the left and right waveguides  86  towards the left and right eye boxes  60  for viewing by the user. 
     In an illustrative arrangement, adjustable optical component  94  is a spatially addressable adjustable light modulator formed using a material with an electrically adjustable light transmission such as guest-host liquid crystal material. This material may be characterized by visible light transmission Tvis that varies as a function of applied voltage V (e.g., alternating-current peak-to-peak voltage), as shown by curve  95  of  FIG.  3   . When the amount of voltage across a layer of this material is less than threshold voltage VT, transmission Tvis will be relatively high and when the amount of applied voltage is more than the threshold voltage VT, transmission Tvis will be relatively low. 
       FIG.  4    is a cross-sectional side view of component  94 . As shown in the illustrative configuration of  FIG.  4   , component  94  may have a first electrode layer (first electrode)  96  and a second electrode layer (second electrode)  106 . Electrically adjustable optical material  104  may be interposed between layers  96  and  106 . Layer  96  may have transparent substrate  102 , transparent conductive layer  100 , and a series of contacts  98  along the periphery of component  94 . Contacts  98  are segmented and run along the left and right edges of conductive layer  100  parallel to the X-axis and make electrical connections to different portions of layer  100 . Layer  106  may have transparent substrate  108 , transparent conductive layer  110 , and contacts  112 . Contacts  112  are segmented and run along the front edge (out of the page edge) and rear edge (into the page edge) of layer  110  parallel to the Y-axis and make electrical connections to different portions of layer  110 . 
     Transparent substrate layers  102  and  108  may be formed from glass, clear polymer, or other transparent material. Transparent conductive layers  100  and  110  may be formed from indium tin oxide, silver nanowires, carbon nanotubes, and/or other transparent conductive material. Layers  100  and  110  may be configured to exhibit electrical anisotropy. In particular, layer  100  may be configured to exhibit a conductivity C100Y in the Y direction that is greater than its conductivity C100X in the X direction and therefore to exhibit a sheet resistance in the Y direction that is less than its sheet resistance in the X direction. The values of the sheet resistance are finite (e.g., there are electrical paths in both the X and Y directions when signals are applied along the sides of component  94 ). The ratio of C100Y/C100X may be at least 2, at least 5, at least 7, at least 10, less than 100, or other suitable value. Layer  110  may be configured to exhibit a conductivity C110X in the X direction that is greater than its conductivity C110Y in the Y direction and therefore to exhibit a sheet resistance in the X direction that is less than its sheet resistance in the Y direction. The ratio of C110X/C110Y may be at least 2, at least 5, at least 7, at least 10, less than 100, or other suitable value. The X and Y directions of  FIG.  4    are orthogonal. If desired, electrically anisotropic materials can have sheet resistances that are maximized and minimized along respective first and second directions that are different but not perpendicular to each other. 
       FIG.  5    is a top view of electrode  96 . As shown in  FIG.  5   , a spatially varying voltage Vapplied may be applied across different contacts  98  on the edges of layer  110 . In the  FIG.  5    example, a reduced value of Vapplied is applied to the middle of 5 pairs of contacts  98 . The high conductivity (and low sheet resistance) of layer  100  in the Y direction relative to the X direction causes this reduced voltage to extend along the Y dimension without spreading significantly in the X direction (due to the larger voltage drops experienced in the X direction due to the relatively high sheet resistance of layer  100  in the X direction). As a result, voltage V in layer  100  exhibits a dip as shown by line  113  in the middle of layer  110 .  FIG.  6    is a top view of electrode  106 . As shown in  FIG.  6   , electrodes  112  may be used to supply a desired localized voltage chain along a section of layer  110  that extends parallel to the X axis. In particular, Vapplied may be locally higher in the middle of 5 pairs of contacts  112  that extend along the Y axis. The high conductivity (and low sheet resistance) of layer  110  in the X dimension relative to the Y direction causes the localized increase in Vapplied to spread along the X dimension without spreading significantly in the perpendicular Y direction, so that voltage V in layer  110  exhibits a rise in the middle of layer  110  as shown by line  115  of  FIG.  6   . The localized rise in the voltage in layer  110  along the Y direction combined with the localized decrease in the voltage in layer  100  along the X direction creates a localized area such as region  117  of  FIG.  7    in which the difference between the voltage in layer  110  and the voltage in layer  100  is decreased relative to the rest of the layer. In this example, the localized change results in a voltage difference (and electric field difference across layer  104 ) that is less than the rest of layer  104 . If desired, the localized change may result in a voltage difference (and electric field difference across layer  104  in the Z dimension) that is locally greater (e.g., maximized) relative to the rest of layer  104 . 
     During operation, control circuitry  12  may adjust the voltages Vapplied applied to the contacts of component  94 . By adjusting the locations of the changes in voltage Vapplied in this way (e.g., by supplying appropriate voltages to various sets of contacts  98  and contacts  112 ), the location of locally adjusted voltage region (in which the electric field through electrically adjustable optical material layer  104  is adjusted up or down relative to the rest of layer  104 ) can be varied as desired (e.g., to place a localized low transmission region in a desired location relative to clear portions of layer  104 ), to adjust the power of a lens and/or the location in the X-Y plane of the lens, etc. 
     When it is desired to create a localized change in light transmission, layer  104  may be formed from a material such as a guest-host liquid crystal material that exhibits a change in light transmission versus applied voltage of the type shown in  FIG.  3   . When it is desired to create a controllable localized change in the phase of the light passing through layer  104  (e.g., to create a dynamically adjustable lens), layer  104  may be formed from a liquid crystal material. A liquid crystal layer may alter the phase of light rays traveling through the liquid crystal layer in proportion to the magnitude of the applied electric field across the layer (parallel to the Z dimension). When layer  104  is a liquid crystal layer, a lens may be formed in an area such as area  117  or other selected area and this area (and its strength) can be adjusted by applying various voltages Vapplied to the contacts of component  94 . 
     With an illustrative configuration, layer  100  is formed from a blanket conductive film such as a thin-film coating layer of indium tin oxide, carbon nanotubes, silver nanowires, or other transparent conductive material. The thickness of the film may be 0.1-0.5 microns, at least 0.01 microns, at least 0.05 microns, at least 0.1 microns, at least 0.4 microns, less than 100 microns, less than 10 microns, less than 1 micron, or other suitable thickness. The blanket film may or may not exhibit electrical anisotropy in its unpatterned state. To create and/or enhance the electrical anisotropy of layer  100 , layer  100  may be patterned by providing layer  100  with openings. The openings represent portions of the layer without electrically conductive material and therefore affect the sheet resistance of the layer. By patterning the openings in an appropriate pattern, anisotropy in the sheet resistance of the layer may be achieved. By ensuring that the openings are sufficiently small, the visibility of the openings to the user may be reduced or eliminated. 
     The openings may, for example, be elongated segmented trenches such as trenches  116  of  FIG.  8   . Trenches  116  may extend in segmented and staggered lines that form columns extending along the Y dimension (as shown in  FIG.  8   ) and/or segmented and staggered lines that form rows extending along the X dimension. In trenches  116 , no conductive material is present, so conductivity is low (e.g., zero) and resistivity is high (e.g., infinite). Current flowing along the Y direction (in the  FIG.  8    example), can travel directly along the paths between respective columns such as path  119 . Current flowing generally along the X direction (in the  FIG.  8    example) can travel only along meandering indirect paths such as path  118 . Because paths  119  are shorter (per unit of Y dimension) than paths  118  are (per unit of X dimension), the conductivity of layer  100  is greater along the Y dimension (and sheet resistance is less) than the X dimension (e.g., the sheet resistance of layer  100  exhibits anisotropy because the sheet resistance of patterned layer  100  is less along the Y dimension than the X dimension). 
     Trenches  116  may be relatively small so as to avoid creating undesired visual artifacts. The electrical anisotropy (and the nature of visual artifacts) can be adjusted by adjusting the length of trenches  116  along the Y dimension, the width of trenches  116  along the X dimension, and the spacing between adjacent trenches  116  in the X and Y dimensions. As an example, trenches  116  may be less than 65 microns long (or less than 40 microns, less than 20 microns, or other suitable length) to ensure that trenches  116  are not visible to the user of device  10  during operation. Configurations in which trenches  116  are at least 20 microns in length, less than 500 microns in length, or other suitable lengths may also be used. The width of trenches  116  may be about 2 microns (or at least 0.5 microns, less than 10 microns, or other suitable width). The separation between trenches  116  in the X dimension may be about 8-125 microns and the separation between trenches  116  in the Y dimension may be about 2 microns, at least 0.2 microns, less than 10 microns, 1-5 microns, or other suitable size. 
     In the example of  FIG.  9   , W-shaped trenches  116  have been formed in layer  100 , resulting in a greater sheet resistance (and lower conductivity) for layer  100  in the Y dimension than in the X dimension. The lines of W-shaped trenches of  FIG.  9    may be separated from each other by a distance S of at least 5 microns, at least 20 microns, at least 25 microns, at least 65 microns at least 125 microns, less than 500 microns, less than 300 microns, or other suitable distance. The width of each trench  116  may be at least 1 microns, less than 3 microns, 2 microns, or other suitable size. The gaps G between adjacent W-shaped trenches  116  may be at least 2 microns, at least 3 microns, at least 5 microns, less than 25 microns, less than 20 microns, 10-20 microns, or other suitable distance. The half-width L of each trench  116  may be at least 20 microns, less than 500 microns, or other suitable size. The cumulative length of each W-shaped trench may be 10-500 microns, at least 50 microns, less than 400 microns, less than 1000 microns, or other suitable length. The individual portions (line segments) of each W-shaped trench may be oriented at an angle of 45°, at least 25°, less than 70°, 30-60°, or other suitable angle with respect to the X and Y directions. By arranging trenches  116  diagonally to the user&#39;s frame of reference, the ability of the user&#39;s eyes to discern the presence of trenches  116  may be reduced and undesired visual artifacts due to the presence of trenches  116  can therefore be minimized. 
     If desired. W-shaped trenches may have curved shapes that form undulating W-shapes, trenches  116  may have S-shapes or other sinuous shapes (e.g., other non-straight shapes), or may have any other shapes with curved and/or straight portions. S-shaped trenches and trenches with other shapes and the spacing between trenches may be chosen to help reduce light diffraction effects and/or visibility to a user. In general, trenches  116  may have any shapes and patterns that help create electrical anisotropy while spreading out diffraction to prevent constructive interference and visual artifacts. 
     Contacts  98  may be formed from thin-film metal coating layers that are patterned (e.g., using lithography, etc.) on the blanket film forming electrode layer  100 . Contacts  112  may likewise be formed from a patterned thin-film metal layer on layer  110 . Along the edge of component  94 , there is a potential for capacitive coupling across trenches  116  (e.g., when alternating-current drive signals Vapplied are being applied to component  94  to adjust transmission in a guest-host liquid crystal layer, etc.). This has the potential to lead to undesired parasitic power consumption. To help reduce or eliminate this power loss, trenches  116  may be provided with locally widened portions adjacent to the contacts. For example, in layer  100 , trenches  116  may be locally widened to form locally widened portions  120  adjacent to contacts  98 , as shown in  FIGS.  10  and  11   . The width of trenches  116  may, for example, be increased by a factor of at least 2, at least 5, 5-20, at least 10, less than 20, or other suitable amount along the X direction for a distance of at least 10 microns, at least 20 microns, 15-30 microns, less than 100 microns, or other suitable distance from the edges of contacts  98  along the Y direction. 
     System  8  may gather and use personally identifiable information. It is well understood that the use of personally identifiable information should follow privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining the privacy of users. In particular, personally identifiable information data should be managed and handled so as to minimize risks of unintentional or unauthorized access or use, and the nature of authorized use should be clearly indicated to users. 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20200415
Publication Date: 20231121
Grant Date: 20231121
Priority Date: 20190612
Inventors: BAYAT, Khadijeh
YUEN, AVERY P.
WANG, CHAOHAO
ZHANG, RUNYU
ZHAO, Xianwei
LI, XIAOKAI
LI, YANG
GE, ZHIBING
PAI, ALEX H.
Assignee: APPLE INC
CPC Classifications: [{"code": "G02F1/13439", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02B27/0172", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/1343", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/13725", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/29", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B2027/0118", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02F1/0102", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02F1/1343", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02F1/13439", "inventive": true, "first": true, "tree": "[]"}, {"code": "G02F1/13439", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/13725", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B27/0172", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B2027/0118", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02F1/13439", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/13725", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B27/0172", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02B2027/014", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B2027/0118", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02B27/0172", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/13725", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/29", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/1343", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 73745966