PATENT DOCUMENT

Publication Number: US-11592873-B2
Application Number: US-202016791905-A
Country: US
Kind Code: B2

Title: Display stack topologies for under-display optical transceivers

Abstract:
In some embodiments, a display stack includes a set of light-emitting elements, and a display backplane that includes a set of conductors and is electrically coupled to the set of light-emitting elements. A conductor in the set of conductors has a length, and a curved edge extending along at least a portion of the length. In some embodiments, a display stack includes a set of light-emitting elements; a set of transistors, electrically coupled to the set of light-emitting elements; and a set of conductors, electrically coupled to the set of transistors. The set of transistors may be electrically coupled to the set of conductors at a set of conductive pads. A plurality of conductive pads in the set of conductive pads is coupled to a single conductor in the set of conductors. The single conductor approaches different conductive pads in the plurality of conductive pads at different angles.

Claims:
What is claimed is: 
     
       1. A display stack, comprising:
 a display including a set of light-emitting elements; 
 a display backplane, electrically coupled to the set of light-emitting elements and including a set of conductors; and 
 an optical transceiver positioned behind the display and including an optical transmitter and an optical receiver; wherein, 
 a conductor in the set of conductors has,
 a length; and 
 a curved edge extending along at least a portion of the length; and 
 
 light emitted by the optical transmitter impinges on the curved edge, the curved edge suppressing or enhancing optical crosstalk between the optical transmitter and the optical receiver. 
 
     
     
       2. The display stack of  claim 1 , wherein:
 the conductor is a first conductor, and the length is a first length; 
 the set of conductors comprises a second conductor; 
 the second conductor is adjacent the first conductor; and 
 a spacing between the first conductor and the second conductor varies by at least 5%. 
 
     
     
       3. The display stack of  claim 1 , wherein:
 the length of the conductor includes a first portion coupled to a second portion; and 
 the second portion forms an obtuse angle with respect to the first portion. 
 
     
     
       4. The display stack of  claim 3 , wherein:
 the set of light-emitting elements is arranged in an array having a first dimension orthogonal to a second dimension; 
 the conductor has a first end and a second end; and 
 the first end and the second end are aligned in the first dimension or the second dimension. 
 
     
     
       5. The display stack of  claim 3 , wherein a combined length of the first portion and the second portion is greater than a width of the first portion or the second portion. 
     
     
       6. The display stack of  claim 1 , wherein the conductor is one of a source/drain line or a gate line. 
     
     
       7. The display stack of  claim 1 , wherein:
 the length of the conductor extends in a first direction; 
 the optical transmitter is spaced apart from the optical receiver along a second direction, orthogonal to the first direction; and 
 the curved edge extends between, and is offset from, the optical transmitter and the optical receiver. 
 
     
     
       8. The display stack of  claim 1 , wherein:
 the length of the conductor extends in a first direction; and 
 the optical transmitter is spaced apart from the optical receiver along the first direction. 
 
     
     
       9. A display stack, comprising:
 a set of light-emitting elements; 
 a set of transistors, electrically coupled to the set of light-emitting elements; and 
 a set of conductors, electrically coupled to the set of transistors; wherein, 
 the set of transistors is electrically coupled to the set of conductors at a set of conductive pads; 
 a plurality of conductive pads in the set of conductive pads is coupled to a single conductor in the set of conductors; 
 the single conductor approaches a first conductive pad in the plurality of conductive pads at a first angle; and 
 the single conductor approaches a second conductive pad in the plurality of conductive pads at a second angle different from the first angle. 
 
     
     
       10. The display stack of  claim 9 , wherein the set of conductors comprises:
 a first set of conductors disposed in a first layer; and 
 a second set of conductors disposed in a second layer; wherein, 
 each conductor in the first set overlaps multiple conductors in the second set. 
 
     
     
       11. The display stack of  claim 9 , wherein:
 the single conductor is a first conductor; 
 the set of conductors includes a second conductor adjacent the first conductor; 
 the first conductor has a first cross-section, and the first cross-section is adjacent a second cross-section of the second conductor; and 
 the first cross-section has a first width that differs from a second width of the second cross-section. 
 
     
     
       12. The display stack of  claim 9 , wherein:
 the single conductor is a first conductor; 
 the set of conductors includes a second conductor and a third conductor; 
 the second conductor is disposed between the first conductor and the third conductor; and 
 a first spacing between the first conductor and the second conductor varies differently than a second spacing between the second conductor and the third conductor. 
 
     
     
       13. The display stack of  claim 9 , wherein:
 the single conductor has a length and a width; and 
 the width varies along the length. 
 
     
     
       14. An electronic device, comprising:
 a display including a set of light-emitting elements; 
 a display backplane, electrically coupled to the set of light-emitting elements and including,
 a first set of conductors disposed in a first layer; 
 a second set of conductors disposed in a second layer; and 
 a set of anodes disposed in a third layer; and 
 
 an optical transceiver positioned behind the display backplane, the optical transceiver including an optical transmitter and an optical receiver; wherein, 
 the first layer, the second layer, and the third layer are stacked; 
 a first conductor in the first set and a second conductor in the second set have edges that overlap at a non-perpendicular angle; and 
 an anode in the set of anodes has at least one non-linear edge, the at least one non-linear edge suppressing or enhancing optical crosstalk between the optical transmitter and the optical receiver. 
 
     
     
       15. The electronic device of  claim 14 , further comprising:
 a set of transistors; wherein, 
 conductors in the first set of conductors are electrically coupled to sources or drains of transistors in the set of transistors; and 
 conductors in the second set of conductors are electrically coupled to gates of the transistors in the set of transistors. 
 
     
     
       16. The electronic device of  claim 14 , wherein:
 at least one conductor in the first set of conductors or the second set of conductors has,
 an average width; and 
 a lateral wander spanning at least 125% of the average width.

Description:
FIELD 
     The described embodiments relate to electronic devices (e.g., smartphones, tablet computers, laptop computers, wearable devices, standalone or wall-mounted display screens, and other devices) having under-display optical transceivers, and to display stack topologies that can improve the performance of such under-display optical transceivers. 
     BACKGROUND 
     In some cases, it may be desirable to determine whether an object or user is proximate to a device, to determine the distance between an object or user and a device, or to determine a velocity or acceleration of an object or user with respect to a device. It may also be desirable to capture a two-dimensional (2D) or three-dimensional (3D) image of an object or user that is proximate to a device. In some cases, the 2D or 3D image may be an image of a fingerprint, a face, or a scene in a field of view (FoV). In some cases, it may be useful to wirelessly transmit or receive information between devices. It may also be useful to acquire images or data pertaining to a device&#39;s environment. In all of these cases, the measurements, images, or other data may be sensed or acquired optically. 
     SUMMARY 
     Embodiments of the systems, devices, methods, and apparatus described in the present disclosure are directed to under-display optical transceivers. In accordance with described techniques, an optical transceiver may be positioned under (or behind) a device&#39;s display, and light may be transmitted and received through translucent apertures extending from a front surface to a back surface of the display. In this manner, an optical transceiver may transmit and receive “through” a display. When an optical transceiver is positioned under a device&#39;s display, a portion of the device&#39;s display surface does not have to be reserved for the optical transceiver, and in some cases the device&#39;s display area may be increased. 
     In a first aspect, the present disclosure describes a device including a display stack. The display stack may include a set of light-emitting elements, and a display backplane that includes a set of conductors and is electrically coupled to the set of light-emitting elements. A conductor in the set of conductors may have a length, and a curved edge extending along at least a portion of the length. 
     In another aspect, the present disclosure describes another display stack. The display stack may include a set of light-emitting elements; a set of transistors, electrically coupled to the set of light-emitting elements; and a set of conductors, electrically coupled to the set of transistors. The set of transistors may be electrically coupled to the set of conductors at a set of conductive pads. A plurality of conductive pads in the set of conductive pads may be coupled to a single conductor in the set of conductors. The single conductor may approach a first conductive pad in the plurality of conductive pads at a first angle, and approach a second conductive pad in the plurality of conductive pads at a second angle. 
     In still another aspect of the disclosure, an electronic device is described. The electronic device may include a first set of conductors disposed in a first layer, and a second set of conductors disposed in a second layer. The first layer and the second layer may be stacked. A first conductor in the first set and a second conductor in the second set may have edges that overlap at a non-perpendicular angle. 
     In addition to the exemplary aspects and embodiments described above, further aspects and embodiments will become apparent by reference to the drawings and by study of the following description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure will be readily understood by the following detailed description in conjunction with the accompanying drawings, wherein like reference numerals designate like structural elements, and in which: 
         FIGS.  1 A and  1 B  show an example embodiment of a device having a display and an under-display optical transceiver; 
         FIGS.  2 A and  2 B  show an example elevation of a display stack including an optical transceiver, and illustrate light that propagates through the display stack; 
         FIGS.  3 A- 3 D  show example plan views of various conductors and anodes in a display stack; 
         FIG.  4    shows the display stack described with reference to  FIGS.  2 A- 2 B , and illustrates light that diffracts around, or reflects or scatters from, various components of the display stack; 
         FIGS.  5 A- 5 D  show example plan views of various conductors and anodes in a display stack, which conductors and anodes have features designed to reduce or minimize the amount of light that propagates from an under-display optical transmitter to an under-display optical receiver; 
         FIGS.  6 A- 6 F  show various example placements of optical transceiver components under a display stack, and illustrate how curved, angled, and/or varied features of conductors and anodes within a display stack, and/or the orientations of such elements, may suppress or enhance the diffraction, reflection, and/or scatter of light in one or more directions; and 
         FIG.  7    shows an example electrical block diagram of an electronic device. 
     
    
    
     The use of cross-hatching or shading in the accompanying figures is generally provided to clarify the boundaries between adjacent elements and also to facilitate legibility of the figures. Accordingly, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, element proportions, element dimensions, commonalities of similarly illustrated elements, or any other characteristic, attribute, or property for any element illustrated in the accompanying figures. 
     Additionally, it should be understood that the proportions and dimensions (either relative or absolute) of the various features and elements (and collections and groupings thereof) and the boundaries, separations, and positional relationships presented therebetween, are provided in the accompanying figures merely to facilitate an understanding of the various embodiments described herein and, accordingly, may not necessarily be presented or illustrated to scale, and are not intended to indicate any preference or requirement for an illustrated embodiment to the exclusion of embodiments described with reference thereto. 
     DETAILED DESCRIPTION 
     Reference will now be made in detail to representative embodiments illustrated in the accompanying drawings. It should be understood that the following description is not intended to limit the embodiments to one preferred embodiment. To the contrary, it is intended to cover alternatives, modifications, and equivalents as can be included within the spirit and scope of the described embodiments as defined by the appended claims. 
     To maximize the display area of an electronic device, an optical transceiver may be positioned behind the active area of a device&#39;s display. An optical transceiver (or optical sensing transceiver) may be variously configured or deployed as: a proximity sensor (or ranging sensor); a two-dimensional (2D) or three-dimensional (3D) camera in combination with a flood illuminator or structured light source; a bio-authentication sensor (e.g., an infrared (IR) facial recognition sensor or fingerprint sensor); an eye/gaze tracker, device tracker, or other optical tracking system; an optical communication system or wireless communicator or controller; a time-of-flight (ToF) sensor (e.g., a short pulse optical source and a single-photon avalanche-diode (SPAD) detector or SPAD array); and so on. 
     When an optical transceiver is positioned under a device&#39;s display, an area adjacent the display does not have to be reserved for one or more components of the transceiver (e.g., the transceiver&#39;s transmitter or receiver), and in some cases the size of the device&#39;s display area may be increased. However, an impediment to positioning an optical sensor under a display is the inclusion of many opaque, partially non-transmissive, or laterally non-transmissive elements in the display stack. Opaque, partially non-transmissive, or laterally non-transmissive elements may include, for example, light-emitting elements, drive circuits or the transistors thereof, conductive traces that route electrical signals to the drive circuits, optical, electrical, physical, and/or chemical shielding or confining elements, touch sensing and/or force sensing metal traces, and so on. 
     For purposes of this disclosure, light-emitting elements are deemed to include semiconductor light-emitting elements, such as light-emitting diodes (LEDs); semiconductor-driven electroluminescent light-emitting elements, such as organic LEDs (OLEDs) that include organic materials charged by thin-film transistors; and other types of light-emitting elements. Elements in an OLED display that may be opaque, partially non-transmissive, or laterally non-transmissive include, for example, organic light-emitting elements, the anode(s) and/or cathode(s) that contact the organic light-emitting elements, the thin-film transistors (TFTs) used to drive (or in some cases sense or otherwise control) the organic light-emitting elements, and the TFT metal traces that route signals to or from the TFTs, anode(s), and/or cathode(s). 
     The multiple layers of opaque, partially non-transmissive, or laterally non-transmissive elements in a display stack can reflect, absorb, diffuse, or diffract light entering the front or back surface of the display stack, and can provide high transmission loss (low throughput) for light passing through the display stack. In fact, the density of opaque, partially non-transmissive, or laterally non-transmissive elements in a display stack can make the display stack seem relatively opaque and function as a high-loss optical mask. Furthermore, the small feature size (e.g., micrometer (μm) scale) of opaque, partially non-transmissive, or laterally non-transmissive elements (e.g., anode(s), cathode(s), TFT metal traces, and touch metal traces), in combination with their density, tends to increase the reflectivity of the display stack and increase the extent to which light diffracts as it passes between and around elements in the display stack. In some cases, a display stack may allow approximately 1-2% of visible light to pass, and allow approximately 1-4% of infrared light to pass. 
     One potential solution to this is to fabricate some of the display stack&#39;s opaque elements (e.g., the conductive traces) as transparent elements. For example, conductive traces may be made of indium-tin-oxide (ITO). However, transparent elements are often associated with undesirable costs, such as higher sheet resistance. Furthermore, and in the case of OLED displays, a highly reflective and largely opaque surface is needed under the light-emitting elements of the OLED to maximize OLED optical extraction. Also, transparent conductive traces may allow organic material to be exposed to optical radiation from an under-display optical emitter, which can cause the organic material to heat, glow, age, degrade, and so on. 
     Of particular concern for an under-display optical transceiver, and especially an under-OLED display optical transceiver, are the conductive traces (e.g., anode metal traces) that route electrical signals to or from the TFTs (or to/from the drive or sense circuits) that are used to drive, sense, or otherwise control the display&#39;s light-emitting elements. The conductive traces may provide power and control signals to the light-emitting elements (or pixels), and may read data from the pixels (e.g., from the thin-film transistor(s) (TFT(s)) of every of pixel). The conductive traces are typically included in multiple layers of the display stack, and may be oriented in different directions (e.g., orthogonal or otherwise overlapping directions) such that they form a mesh of conductive traces. In some cases, the conductive traces may cover 85-95% of the surface area of a display stack, and may thus prevent light from passing through approximately 85-95% of a display stack. This greatly reduces the signal-to-noise ratio (SNR) and dynamic range of an optical transceiver positioned in an under-display configuration. The conductive traces are not only opaque, but in many cases are highly reflective. Furthermore, the number and density of the conductive traces can cause them to act as a diffraction grating. 
     As a result of their properties individually, and their layout collectively, the conductive traces within a display stack can lead to significant crosstalk between the optical transmission and optical reception components of an under-display optical transceiver, which may further reduce the SNR and dynamic range of the optical transceiver. Still further, the regular pitch of the TFT metal traces (usually equal to an integer or fraction of the display&#39;s pixel pitch) can make the mesh of TFT metal traces an effective diffraction grating. Regardless, there exist translucent (and sometimes transparent) apertures between the conductive traces, and some of these translucent apertures typically extend from the front surface to the back surface of a display stack. 
     The reflective properties of the conductive traces and other components within a display stack, alone or in combination with the diffraction effects caused by these components, can also increase the incidence of direct crosstalk between an optical emitter and an optical receiver (i.e., crosstalk caused by the propagation of light from an optical emitter to an optical receiver, without the light ever reflecting or scattering off an object or medium that is external to the device that includes the display stack). Measurements have shown that, in some cases, the increase in the incidence of direct crosstalk can be an order of magnitude or more greater than the incidence of direct crosstalk for an optical emitter and optical transceiver positioned directly below a transparent cover (e.g., a cover glass). 
     The present disclosure describes systems, devices, methods, and apparatus in which the topology of a display stack is optimized to mitigate the incidence of direct crosstalk between an optical emitter and an optical receiver (e.g., components of an under-display optical transceiver) positioned under a display. 
     These and other embodiments are discussed with reference to  FIGS.  1 A- 7   . However, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes only and should not be construed as limiting. 
     Directional terminology, such as “top”, “bottom”, “upper”, “lower”, “front”, “back”, “over”, “under”, “above”, “below”, “left”, “right”, etc. is used with reference to the orientation of some of the components in some of the figures described below. Because components in various embodiments can be positioned in a number of different orientations, directional terminology is used for purposes of illustration only and is in no way limiting. The directional terminology is intended to be construed broadly, and therefore should not be interpreted to preclude components being oriented in different ways. The use of alternative terminology, such as “or”, is intended to indicate different combinations of the alternative elements. For example, A or B is intended to include, A, or B, or A and B. 
       FIGS.  1 A and  1 B  show an example of a device  100  having a display  104  and an under-display optical transceiver  118 . More particularly,  FIG.  1 A  shows a perspective view of the front of the device  100 , and  FIG.  1 B  shows an elevation of a side of the device  100  (taken from the view of sight line  1 B- 1 B in  FIG.  1 A ). The device&#39;s dimensions and form factor, including the ratio of the length of its long sides to the length of its short sides, suggest that the device  100  is a mobile phone (e.g., a smartphone). However, the device&#39;s dimensions and form factor are arbitrarily chosen, and the device  100  could alternatively be any portable electronic device, including, for example, a mobile phone, tablet computer, laptop computer, portable music player, health monitoring device, wearable device (e.g., an electronic watch or health monitoring device), portable terminal, or other portable or mobile device. The device  100  could also be a device that is semi-permanently located or installed at a single location (e.g., a display screen, security screen, control screen, electronic kiosk display, or television). 
     The device  100  may include a housing  102  that at least partially surrounds or supports a display  104 . In some examples, the housing  102  may include or support a front cover  106  and/or a rear cover  108 . The front cover  106  may be positioned over the display  104 , and may provide a window through which the display  104  may be viewed. In some embodiments, the display  104  may be attached to (or abut) the housing  102  and/or the front cover  106 . 
     The front of the device  100  may include one or more front-facing cameras  110 , speakers  112 , microphones, or other components  114  (e.g., audio, imaging, or sensing components) that are configured to transmit or receive signals to/from the device  100 . In some cases, a front-facing camera  110 , alone or in combination with other sensors, may be configured to operate as a bio-authentication sensor (e.g., a facial recognition sensor). The device  100  may also include various input devices, including a mechanical or virtual button  116  which may be accessible from the front surface (or display surface) of the device  100 . In some cases, the front-facing camera  110 , virtual button  116 , and/or other sensors of the device  100  may be integrated with a display stack of the device  100  and positioned under the display  104 . For example, the front-facing camera(s)  110 , virtual button  116 , and/or other components may be provided by one or more optical transceivers  118  positioned under the display  104 . An under-display optical transceiver  118  may also be configured as (or provide) a proximity sensor; a 2D or 3D camera in combination with a flood illuminator or structured light source; a bio-authentication sensor (e.g., a facial recognition sensor or fingerprint sensor); an eye/gaze tracker, device tracker, or other optical tracking system; an optical communication system; and so on. 
     The device  100  may also include buttons or other input devices positioned along a sidewall  120  of the housing  102  and/or on a rear surface of the device  100 . For example, a volume button or multipurpose button  122  may be positioned along the sidewall  120 , and in some cases may extend through an aperture in the sidewall  120 . By way of example, the rear surface of the device  100  may include a rear-facing camera or other optical sensor. A flash or light source may also be positioned along the rear of the device  100  (e.g., near the rear-facing camera). In some cases, the rear surface of the device  100  may include multiple rear-facing cameras. 
     The display  104  may include one or more light-emitting elements including, for example, LEDs, OLEDs, a liquid crystal display (LCD), an electroluminescent display (EL), or other types of light-emitting elements. The display  104  may also include, or be associated with, one or more touch and/or force sensors that are configured to detect a touch and/or a force applied to a surface of the front cover  106 . 
     The various components of the housing  102  may be formed from the same or different materials. For example, the sidewall  120  may be formed using one or more metals (e.g., stainless steel), polymers (e.g., plastics), ceramics, or composites (e.g., carbon fiber). In some cases, the sidewall  120  may be a multi-segment sidewall including a set of antennas. The antennas may form structural components of the sidewall  120 . The antennas may be structurally coupled (to one another or to other components) and electrically isolated (from each other or from other components) by one or more non-conductive segments of the sidewall  120 . The front cover  106  may include, for example, one or more of glass, a crystal (e.g., sapphire), or a transparent polymer (e.g., plastic) that enables a user to view the display  104  through the front cover  106 . In some cases, a portion of the front cover  106  (e.g., a perimeter portion of the front cover) may be coated with an opaque ink to obscure components included within the housing  102 . The rear cover  108  may be formed using the same material(s) that are used to form the sidewall  120  or the front cover  106 . In some cases, the rear cover  108  may be part of a monolithic element that also forms the sidewall  120  (or in cases where the sidewall  120  is a multi-segment sidewall, those portions of the sidewall  120  that are non-conductive). In still other embodiments, all of the exterior components of the housing  102  may be formed from a transparent material, and components within the device  100  may or may not be obscured by an opaque ink or opaque structure within the housing  102 . 
     The front cover  106  may be mounted to the sidewall  120  to cover an opening defined by the sidewall  120  (i.e., an opening into an interior volume in which various electronic components of the device  100 , including the display  104  and optical transceiver  118 , may be positioned). The front cover  106  may be mounted to the sidewall  120  using fasteners, adhesives, seals, gaskets, or other components. 
     A display stack or device stack (hereafter referred to as a “stack”) including the display  104  may be attached (or abutted) to an interior surface of the front cover  106  and extend into the interior volume of the device  100 . In some cases, the stack may include a touch sensor (e.g., a grid of capacitive, resistive, strain-based, ultrasonic, or other type of touch sensing elements), or other layers of optical, mechanical, electrical, or other types of components. In some cases, the touch sensor (or part of a touch sensing system) may be configured to detect a touch applied to an outer surface of the front cover  106  (e.g., to a display surface of the device  100 ). 
     In some cases, a force sensor (or part of a force sensing system) may be positioned within the interior volume below and/or to the side of the display  104 . In some cases, the force sensor (or force sensing system) may be triggered in response to the touch sensor detecting one or more touches on the front cover  106  (or a location or locations of one or more touches on the front cover  106 ), and may determine an amount of force associated with each touch, or an amount of force associated with the collection of touches as a whole. Alternatively, operation of the touch sensor (or touch sensing system) may be triggered in response to the force sensor (or force sensing system) detecting an amount of force (e.g., an amount of force exceeding a threshold amount) on the front cover  106 . Alternatively, the force sensor (or force sensing system) may be configured to detect a location or centroid of one or more touches, thereby functioning as both a force sensor and a touch sensor. 
       FIG.  1 B  shows light  124  being emitted from an optical transmitter (or optical emitter) of an optical transceiver  118  positioned under (or behind) the display  104 . The emitted light  124  may travel from the optical transmitter toward the front cover  106 , and may pass through the front cover  106 . After passing through the front cover  106 , the emitted light  124  may travel toward an object  126 , such as a user&#39;s finger, face, or ear, reflect from the object  126 , and travel back toward the device  100  as reflected light  128 . The reflected light  128  may pass through the display  104  and be received by an optical receiver of the optical transceiver  118 . A processor of the device  100  may then determine a proximity of the object  126  to the device  100 . The processor may also or alternatively make other determinations based on the emitted and received light  124 ,  128 , or based on light received (but not emitted) by the device  100 . For example, the processor may analyze a 2D or 3D image acquired by the optical transceiver  118 ; or enroll or authenticate a user&#39;s face or fingerprint; or determine the distance or direction to, or the topography, position, or motion of, the object  126 . 
       FIG.  2 A  shows an example elevation of a display stack  200 . The display stack  200  may include a cover  202 , a touch sensor  204 , a display  206 , and/or an optical transceiver  208 . The touch sensor  204  may be positioned under the cover  202 , the display  206  may be positioned under the touch sensor  204 , and the optical transceiver  208  may be positioned under the display  206 . In some cases, the display stack  200  may be included in the device  100  described with reference to  FIGS.  1 A and  1 B . With respect to  FIG.  2 A , “under” means more interior to a device that includes the display stack  200 . 
     The cover  202 , touch sensor  204 , display  206 , and/or optical transceiver  208  may be abutted or attached to one another (e.g., using one or more adhesives or other materials). The cover  202  may include, for example, one or more of glass, a crystal (e.g., sapphire), or a transparent polymer (e.g., plastic) that enables a user to view the display  206  through the cover  202 . The cover  202  may be more or less rigid, may provide an exterior surface that a user may touch or press, and may protect the touch sensor  204 , display  206 , optical transceiver  208  and/or other components that are interior to a device. 
     The touch sensor  204  may include an array (or grid) of touch sensing elements, with each touch sensing element being configured to generate (or alter) an output signal when the cover  202  is touched at a location above and proximate to the touch sensing element. The touch sensing elements may use capacitive, resistive, ultrasonic, optical, or other touch sensing technologies. Depending on the technology used, the touch sensor  204  may include discrete touch sensing elements (e.g., strain gauges or ultrasonic transceivers) or arrays of elements that cooperate to form touch sensing elements (e.g., first and second layers of electrodes in which a first set of electrodes in a first layer is oriented in a first direction, a second set of electrodes in a second layer is oriented in a second direction, and a different touch sensing element is formed at each location where an electrode in the first set overlaps an electrode in the second set). 
     The display  206  may be any type of electronic display, such as any of the display types described with reference to  FIGS.  1 A- 1 B . By way of example, the display  206  may be an OLED display. In one example of an OLED display, the display  206  may include a set of light-emitting elements  210 . Alternatively, the light-emitting elements  210  may include LEDs or other types of light-emitting elements. The light-emitting elements  210  may be arranged in an array having two or more dimensions (e.g., in an array having first and second dimensions that are orthogonal to each other and parallel to the exterior surface of the cover  202 ; or in a three-dimensional array having first and second dimensions that are orthogonal to each other and parallel to the exterior surface of the cover  202 , and a third dimension that is perpendicular the exterior surface of the cover  202 ). In the case of an OLED display, the light-emitting elements  210  may be formed using an organic material. The light-emitting elements  210  may have the same or different properties, and may be configured (e.g., color filtered) to emit the same or different colors of light. In some embodiments, the light-emitting elements may include red, green, and blue light-emitting elements arranged in accordance with a particular display pixel layout. 
     The display  206  may include a set of one or more cathodes, which in some cases may take the form of a single planar cathode  212  coupled to first surfaces of the light-emitting elements  210  (e.g., to cover-facing surfaces of the light-emitting elements  210 ). The display  206  may further include a backplane  214  (or display backplane) that is electrically coupled to second surfaces of the light-emitting elements  210  (e.g., to optical transceiver-facing surfaces of the light-emitting elements  210 ). The backplane  214  may include a set of anodes  216  coupled to the set of light-emitting elements  210 . 
     The backplane  214  may include a set of transistors  218  and/or other components (e.g., resistors, capacitors, and so on), and a set of conductive metal traces, conductive traces, and/or conductive vias (collectively and generally referred to herein as a set of conductors  220 ). In some embodiments, the transistors  218  may include TFTs and/or the conductors  220  may include thin film conductors. The conductors  220  may electrically couple the light-emitting elements  210  to the transistors  218  or other components. The conductors  220  may also electrically couple the transistors  218  or other components to each other, to other components within the backplane  214 , and/or to other components outside the backplane  214  (e.g., drivers, sensors, converters, controllers, and so on). Each light-emitting element  210  may be coupled to one or more of the conductors  220  at, or via, one of the anodes  216 , and each transistor  218  may be coupled to one or more of the conductors  220  at, or via, a conductive pad. 
     A backfilm  230 , such as one or multiple layers of polymer material, may be positioned under the backplane  214 . In some cases, the backfilm  230  may function as a substrate on which other layers of the backplane  214  are formed. 
     The optical transceiver  208  may include an optical transmitter  232  and an optical receiver  234 . The optical transmitter  232  may include one or multiple emitters (e.g., one emitter or an array of emitters). The optical receiver  234  may include one or multiple photodetectors, and in some embodiments may include a 2D or 3D camera. 
     The components  232 ,  234  of the optical transceiver  208  may be supported by an optical module frame  236  or housing that is abutted to or attached to the backfilm  230 . In some embodiments, walls of the frame  236  may be adhesively bonded to the backfilm  230  by an adhesive  238 . 
     Optionally, one or more lenses or other optical elements  240  may be attached to the frame  236  such that they are disposed in an optical emission path of the optical transmitter  232 . One or more additional lenses or other optical elements  242  may be attached to the frame  236  such that they are disposed in an optical reception path of the optical receiver  234 . The lenses or other optical elements  240 ,  242  may variously focus, collimate, fan-out, or shape the light  244  emitted by the optical transmitter  232  or the light  254  received by the optical receiver  234 . In some embodiments, the optical transmitter  232  and optical receiver  234 , and/or the optical elements  240  or  242 , may be separated by a light blocking wall  246  or spacer  248  that prevents light  244  emitted by the optical transmitter  232  from impinging directly, or too easily, on the optical receiver  234 . Typically, it is desirable for light  244  emitted by the optical transmitter  232  to impinge on an object  250  external to the cover  202  before being reflected or scattered back toward the optical receiver  234 . 
     In operation, the optical transmitter  232  may emit light  244  toward the cover  202 , and a portion of the light  244  may pass through the display  206  as light  252 . A portion of the light  252  that passes through the display  206  may also pass through the touch sensor  204  and cover  202 , and reflect or scatter from the surface of one or more objects  250 . The object(s)  250  may be on, near, or far from the exterior surface of the cover  202 . A portion of the light that reflects or scatters from the object(s)  250  may pass back through the cover  202 , touch sensor  204 , and display  206 , and may be received by the optical receiver  234 . 
       FIG.  2 B  shows an enlarged portion  260  of the display stack described with reference to  FIG.  2 A . In particular,  FIG.  2 B  shows an enlarged view of the light-emitting elements  210 , anodes  216 , transistors  218 , and conductors  220  of the display  206 . 
     As shown, the conductors  220  may include a first layer  262  of conductors  220  (or first subset of the conductors  220 ), a second layer  264  of conductors  220  (or a second subset of the conductors  220 ), a set of vias  266  that electrically couple the anodes  216  to conductors in the first layer  262  of conductors  220 , and/or additional layers or sets of conductors. Each of the transistors  218  may have source and drain terminals that are respectively coupled to a source line or drain line (source/drain lines), and a gate terminal that is coupled to a gate line in the second layer  264  of conductors  220 . Each of the light-emitting elements  210 , anodes  216 , transistors  218 , and conductors  220  may be opaque, partially non-transmissive, or laterally non-transmissive to the light  244  emitted by the optical transmitter described with reference to  FIG.  2 A . 
     The portion of the light  244  that does not pass through the display  206  may be reflected or scattered within the display  206 , or absorbed by various elements within the display  206 . Some of the light that is reflected or scattered may impinge on the optical receiver  234  without reflecting off of an object external to the device that includes the display  206 . 
       FIGS.  3 A- 3 D  show example plan views of various conductors and anodes, which by way of example may be the conductors and anodes described with reference to  FIGS.  2 A- 2 B . In particular,  FIG.  3 A  shows an example layout  300  of the first layer  262  of conductors  220  (e.g., source/drain lines);  FIG.  3 B  shows an example layout  310  of the second layer  264  of conductors  220  (e.g., gate lines); and  FIG.  3 C  shows an example layout  320  of the anodes  216 .  FIG.  3 D  shows a stackup  330  of the anodes  216 , first layer  262 , and second layer  264 . Each of the conductors  220  may be electrically coupled to, and intersect or overlap, a number of conductive pads  302 . Typically, each source/drain line and gate line will be electrically coupled to a plurality of the conductive pads  302 . 
     The construction of the anodes  216 , conductors  220 , and conductive pads  302  shown in  FIGS.  3 A- 3 D  is typical, with each of these components having straight and closely spaced parallel edges  304 . Furthermore, the interior and exterior corners  306 ,  308  of the conductive pads  302  and anodes  216  are square, and all of these components (and their features) are laid out in a very repetitive manner. Because the anodes  216 , conductors  220 , and conductive pads  302  are generally opaque, light that is emitted toward one side of a display stack including these elements may only pass through translucent or transparent areas  332  that exist between the anodes  216 , conductors  220 , and conductive pads  302 . Or, in some cases, light may pass through partially transmissive portions (if any) of the anodes  216 , conductors  220 , or conductive pads  302 . Other portions of the emitted light may diffract, reflect, or scatter, and may not pass through the stack shown in  FIG.  3 D . In particular, high spatial frequency grating patterns may diffract significant light into large angle components that waveguide through backfilm layers towards one or more optical receivers. In essence, the anodes  216  and conductors  220  function as a highly reflective diffraction grating, which can lead to significant optical crosstalk between the components (e.g., optical transmitter(s) and optical receiver(s)) of an under-display optical transceiver. 
       FIG.  4    shows the display stack  200  described with reference to  FIGS.  2 A- 2 B , but instead of showing the light that is emitted by the optical transmitter  232 , passes through the display  206 , touch sensor  204 , and cover  202 , is reflected by an object  250 , and is received by the optical transmitter  232 ,  FIG.  4    shows portions  400 ,  402  of the emitted light that diffract around, or reflect or scatter from, various components of the display stack  200 . Some of this light  400 ,  402  may impinge on the optical receiver  234  without ever exiting the cover  202 , and may therefore be considered undesirable optical crosstalk. Suppression of this optical crosstalk, or at least large angle waveguiding components thereof, can provide improved under-display optical transceiver performance. Suppression of optical crosstalk can also improve the performance of an under-display optical receiver (or sensor)—e.g., by improving its dynamic range, resolution, or response time; reducing shot noise; increasing SNR; improving uniformity, such as photon counting uniformity in the case of a SPAD; and so on. 
       FIGS.  5 A- 5 D  show example plan views of various conductors and anodes, which by way of example may be the conductors and anodes described with reference to  FIGS.  2 A- 2 B and  4   . In particular,  FIG.  5 A  shows an example layout  500  of the first layer  262  of conductors  220  (e.g., source/drain lines);  FIG.  5 B  shows an example layout  540  of the second layer  264  of conductors  220  (e.g., gate lines); and  FIG.  5 C  shows an example layout  560  of the anodes  216 , in a third layer that is separate from the first and second layers  262 ,  264 .  FIG.  5 D  shows a stackup  580  of the anodes  216 , first layer  262 , and second layer  264 . Each of the conductors  220  may be electrically coupled to, and intersect or overlap, a number of conductive pads  502 . Typically, each source/drain line and gate line will be electrically coupled to a plurality of the conductive pads  502 . 
     The anodes  216 , conductors  220 , and conductive pads  502  shown in  FIGS.  5 A- 5 D  may have non-linear edges (e.g., curved, angular, or otherwise less-straight edges); varying widths; and/or irregular positions, sizes, or shapes of conductive pads  502 . Furthermore, the conductors  220  may have different, loose, or varying widths, spacing, or pitch, or other non-uniform and/or varying features. The features and patterns of the anodes  216 , conductors  220 , and conductive pads  502  may also have less or no repetition in orthogonal (x/y) and diagonal directions. Such features and variations may be designed to suppress or enhance the propagation of diffracted, reflected, and/or scattered light within a display stack. 
     As shown in  FIG.  5 A , one or more of the conductors  220  may have a length  504 , and a curved edge  506  or  508  extending along at least a portion of the length  504 . In some cases, all of the edges of the conductors  220 , but for some of the edges defining the conductive pads  502 , may be curved. Alternatively, the edges of the conductive pads  502  may also be curved; or only some of the edges along the length  504  and/or some of the edges defining the conductive pads  502  may be curved, and other edges may be straight. 
     As shown in  FIG.  5 B , one or more of the conductors  220  may have a length  542 , and one or more edges  544 ,  546  that form non-perpendicular angles with respect to the length  542  (e.g., angled edges). Different edges  544 ,  546  may form different non-perpendicular angles with respect to the length  542 . In some cases, all of the edges of the conductors  220 , but for some of the edges defining the conductive pads  502 , may form non-perpendicular angles with respect to the length  542 . Alternatively, the edges of the conductive pads  502  may also form non-perpendicular angles with respect to the length  542 ; or only some of the edges along the length  542  and/or some of the edges defining the conductive pads  502  may form non-perpendicular angles with respect to the length  542 , and other edges may be perpendicular or parallel to the length  542 . 
     In some embodiments, and as shown in  FIGS.  5 A- 5 B , adjacent conductors (e.g., adjacent first and second conductors  220 ) may have a spacing  510  or  548  that varies along their lengths. In some embodiments, their spacing may vary by at least 5%. In other embodiments, their spacing  510  or  548  may vary up to 100%, up to 200%, or by any amount. In some embodiments, an irrational ratio of change (avoiding a common denominator) may be useful. 
     Each of the conductors  220  may be positioned under an array of light-emitting elements. The array of light-emitting elements may have a first dimension  512  and a second dimension  514 , with the first and second dimensions  512 ,  514  being orthogonal to each other and parallel to the array of light-emitting elements. Each of the conductors  220  may further have first and second ends, with the first and second ends being aligned in one of the first dimension  512  or the second dimension  514 . For purposes of this disclosure, “aligned ends” means that a straight line passes through a portion of each end. Aligned ends may be partially aligned or fully aligned. In some embodiments, the ends of a conductor  220  may not be aligned. 
     In some embodiments, and as also shown in  FIGS.  5 A- 5 B , different portions (e.g., first and second portions  516  and  518 , or  550  and  552 ) of a conductor  220  may form an obtuse angle  520  or  554 . In some embodiments, the combined length of the first portion and the second portion ( 516  and  518 , or  550  and  552 ) may be greater than a width of the first portion or the second portion. 
     In some embodiments, one or more of the conductors  220  shown in  FIGS.  5 A- 5 B  may approach different edges  522 ,  524  of a conductive pad  502  at different angles. See, for example,  FIG.  5 A . In the same or different embodiments, one or more of the conductors  220  may approach a first conductive pad  502  at a first angle, and approach a second conductive pad  502  at a second angle. 
     In some embodiments, a first conductor  220  may have a first cross-section; a second conductor  220 , adjacent the first conductor  220 , may have a second cross-section; and the first cross-section may have a first width  526  that differs from a second width  528  of the second cross-section. 
     In some embodiments, and as shown in  FIGS.  5 A- 5 B , first, second, and third conductors may be positioned adjacent one another, with the second conductor  220  disposed between the first and third conductors  220 , and a first spacing  510  between the first and second conductors  220  may vary differently than a second spacing  530  between the second and third conductors. 
     In some embodiments, a conductor  220  may have a length  504  and a width  532 , and the width  532  may vary along the length  504 . In some embodiments, one or more of the conductors  220  may have a lateral wander that spans at least 125% of the conductor&#39;s average width. In other embodiments, the lateral wander may range from 1% to over 100%. In some embodiments, an irrational ratio of change may be useful—e.g., wandering by 23%, 41%, etc. 
     The conductors  220  shown in  FIG.  5 A  may be arranged in a first layer  262 , and the conductors  220  shown in  FIG.  5 B  may be arranged in a second layer  264 . As shown in  FIG.  5 D , the first and second layers of conductors  220  may be stacked, with each conductor  220  in the first set overlapping multiple conductors  220  in the second set, and each conductor  220  in the second set overlapping multiple conductors  220  in the first set. In some embodiments, a first conductor  220  in the first set and a second conductor  220  in the second set may have edges that overlap at a non-perpendicular angle. In some embodiments, the non-perpendicular angle may be between 45 and 135 degrees. 
     The various curved, angled, and/or varying features of the conductors  220  and anodes  216  may be used to suppress or enhance the diffraction, reflection, and/or scatter of light that is emitted toward a display through the stackup (or display stack)  580 . 
       FIGS.  6 A- 6 F  show various example placements of optical transceiver components under a display stack, and illustrate how the curved, angled, and/or varied features of conductors and anodes within a display stack, and/or the orientations of such elements, may suppress or enhance the diffraction, reflection, and/or scatter of light in one or more directions. 
       FIG.  6 A  shows source/drain lines  600  having lengths that extend in a first direction, and components of an optical transceiver (e.g., an optical transmitter  602  and optical receiver  604 ) that are spaced apart from each other and the source/drain lines  600  along a second direction, orthogonal to the first direction. One or more of the source/drain lines  600  have curved edges that extend between, and are offset from, the optical transmitter  602  and optical receiver  604 . The curved edges may aid in suppressing optical crosstalk between the optical transmitter  602  and optical receiver  604  (e.g., reduce or minimize the amount of light that propagates from the optical transmitter  602  to the first optical receiver  604  without first exiting the device that includes the source/drain lines  600 ). Features and/or orientations of the gate lines  606  and anodes  608  may also aid in suppressing optical crosstalk between the optical transmitter  602  and optical receiver  604 . 
       FIG.  6 B  shows the source/drain lines  600 , gate lines  606 , and anodes  608  described with reference  FIG.  6 A , but shows the optical transmitter  602  and optical receiver  604  spaced apart from each other along a second direction that forms a diagonal with respect to the first direction of the source/drain lines  600 . By way of example, the diagonal is shown to be a 45 degree diagonal. Another useful diagonal angle is 22.5 degrees. In other embodiments, the optical transmitter  602  and optical receiver  604  may be spaced apart from each other in any direction, whether orthogonal or non-orthogonal (and even parallel) to the source/drain lines  600  (i.e., in a direction that forms any angle with respect to, or is parallel to, the source/drain lines  600 ), or orthogonal or non-orthogonal (and even parallel) to the gate lines  606  (i.e., in a direction that forms any angle with respect to, or is parallel to, the gate lines  606 ). In general, the optical transmitter  602  and optical receiver  604  may be spaced apart from each other along any direction in which a display topology provides lower spatial frequencies. 
       FIGS.  6 C and  6 D  show the placement of an additional optical receiver  610  under the source/drain lines  600 . With respect to the view shown in  FIGS.  6 C- 6 D  (and all of  FIGS.  6 A- 6 F ), note that the view of each figure is presented from the vantage point of looking up through a display stack, such that the transceiver components shown on top of each figure are actually “under” a display and other components of the display stack. 
     In  FIG.  6 C , the additional optical receiver  610  is spaced apart from the first optical receiver  604  along the second direction described with reference to  FIG.  6 A , with both optical receivers  604 ,  610  being disposed on one side of the optical transmitter  602 . In  FIG.  6 D , the additional optical receiver  610  is spaced apart from the optical transmitter  602  along the first direction described with reference to  FIG.  6 A . In both embodiments, the curved edges of the source/drain lines  600  may aid in suppressing optical crosstalk between the optical transmitter  602  and the optical receivers  604 ,  610  (e.g., reduce or minimize the amount of light that propagates from the optical transmitter  602  to the first optical receiver  604  without first exiting the device that includes the source/drain lines  600 ). Features and/or orientations of the gate lines  606  and anodes  608  may also aid in suppressing optical crosstalk between the optical transmitter  602  and optical receivers  604 ,  610 . 
       FIGS.  6 E and  6 F  also show the placement of an additional receiver  610  under the source/drain lines  600 . In  FIG.  6 E , the additional optical receiver  610  is spaced apart from the first optical receiver  604  along the second direction described with reference to  FIG.  6 A , with the optical receivers  604 ,  610  being disposed on opposite sides of the optical transmitter  602 . In  FIG.  6 F , the additional optical receiver  610  is spaced apart from the optical transmitter  602  along the first direction described with reference to  FIG.  6 A . In both embodiments, the curved edges may aid in suppressing optical crosstalk between the optical transmitter  602  and the first optical receiver  604  (e.g., reduce or minimize the amount of light that propagates from the optical transmitter  602  to the first optical receiver  604  without first exiting the device that includes the source/drain lines  600 ), but enhance optical crosstalk between the optical transmitter  602  and the second optical receiver  610 . Features and/or orientations of the gate lines  606  and anodes  608  may also aid in suppressing or enhancing optical crosstalk between the optical transmitter  602  and optical receivers  604 ,  610 . 
     In the embodiments described with reference to  FIGS.  6 E and  6 F , differences between the outputs of the first and second optical receivers  604 ,  610 , caused by suppression or enhancement of optical crosstalk, may be used to estimate how much optical crosstalk is affecting the first and/or second optical receiver, so that an optical crosstalk baseline may be subtracted from the signal(s) generated by the first and/or second optical receiver  604 ,  610  (e.g., the difference in optical crosstalk may be used to calibrate the components of an optical transceiver). 
     In some embodiments, the source/drain lines  600 , gate lines  606 , and anodes  608  shown in  FIGS.  6 A- 6 F  may be examples of the conductors  220  described with reference to  FIGS.  2 A- 5 D . In some embodiments, the optical transmitter  602  and optical receivers  604 ,  610  described with reference to  FIGS.  6 C- 6 F  may be spaced apart in other directions, as described, for example, with reference to  FIG.  6 B . 
       FIG.  7    shows a sample electrical block diagram of an electronic device  700 , which electronic device may in some cases take the form of the device described with reference to  FIGS.  1 A and  1 B  and/or have a display stack or under-display optical transceiver as described with reference to  FIGS.  1 A- 6 F . The electronic device  700  may include a display  702  (e.g., a light-emitting display), a processor  704 , a power source  706 , a memory  708  or storage device, a sensor system  710 , or an input/output (I/O) mechanism  712  (e.g., an input/output device, input/output port, or haptic input/output interface). The processor  704  may control some or all of the operations of the electronic device  700 . The processor  704  may communicate, either directly or indirectly, with some or all of the other components of the electronic device  700 . For example, a system bus or other communication mechanism  714  can provide communication between the display  702 , the processor  704 , the power source  706 , the memory  708 , the sensor system  710 , and the I/O mechanism  712 . 
     The processor  704  may be implemented as any electronic device capable of processing, receiving, or transmitting data or instructions, whether such data or instructions is in the form of software or firmware or otherwise encoded. For example, the processor  704  may include a microprocessor, a central processing unit (CPU), an application-specific integrated circuit (ASIC), a digital signal processor (DSP), a controller, or a combination of such devices. As described herein, the term “processor” is meant to encompass a single processor or processing unit, multiple processors, multiple processing units, or other suitably configured computing element or elements. 
     It should be noted that the components of the electronic device  700  can be controlled by multiple processors. For example, select components of the electronic device  700  (e.g., the sensor system  710 ) may be controlled by a first processor and other components of the electronic device  700  (e.g., the display  702 ) may be controlled by a second processor, where the first and second processors may or may not be in communication with each other. 
     The power source  706  can be implemented with any device capable of providing energy to the electronic device  700 . For example, the power source  706  may include one or more batteries or rechargeable batteries. Additionally or alternatively, the power source  706  may include a power connector or power cord that connects the electronic device  700  to another power source, such as a wall outlet. 
     The memory  708  may store electronic data that can be used by the electronic device  700 . For example, the memory  708  may store electrical data or content such as, for example, audio and video files, documents and applications, device settings and user preferences, timing signals, control signals, and data structures or databases. The memory  708  may include any type of memory. By way of example only, the memory  708  may include random access memory, read-only memory, Flash memory, removable memory, other types of storage elements, or combinations of such memory types. 
     The electronic device  700  may also include one or more sensor systems  710  positioned almost anywhere on the electronic device  700 . However, at least one optical transceiver may be positioned under the display  702 , and may be configured to transmit and receive light through the display  702 . The sensor system(s)  710  may be configured to sense one or more types of parameters, such as but not limited to, light; touch; force; heat; movement; relative motion; biometric data (e.g., biological parameters) of a user; proximity of an object; depth of an object; and so on. By way of example, the sensor system(s)  710  may include a heat sensor, a position sensor, a light or optical sensor (e.g., an optical transceiver), an accelerometer, a pressure transducer, a gyroscope, a magnetometer, a health monitoring sensor, and so on. Additionally, the one or more sensor systems  710  may utilize any suitable sensing technology, including, but not limited to, capacitive, ultrasonic, resistive, optical, ultrasound, piezoelectric, and thermal sensing technology. 
     The I/O mechanism  712  may transmit or receive data from a user or another electronic device. The I/O mechanism  712  may include the display  702 , a touch sensing input surface, a crown, one or more buttons (e.g., a graphical user interface “home” button), one or more cameras (including an under-display camera), one or more microphones or speakers, one or more ports such as a microphone port, and/or a keyboard. Additionally or alternatively, the I/O mechanism  712  may transmit electronic signals via a communications interface, such as a wireless, wired, and/or optical communications interface. Examples of wireless and wired communications interfaces include, but are not limited to, cellular and Wi-Fi communications interfaces. 
     The foregoing description, for purposes of explanation, uses specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art, after reading this description, that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of the specific embodiments described herein are presented for purposes of illustration and description. They are not targeted to be exhaustive or to limit the embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art, after reading this description, that many modifications and variations are possible in view of the above teachings.

Metadata:
Filing Date: 20200214
Publication Date: 20230228
Grant Date: 20230228
Priority Date: 20200214
Inventors: XIANG, Xiao
CHEN, TONG
GUI, Fan
WINKLER, MARK T.
TU, Ran
LIN, TSU-HUI
CAI, WENRUI
WANG, YUN
Assignee: APPLE INC
CPC Classifications: [{"code": "G06F3/0421", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F2203/04105", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0412", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/042", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K59/131", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1637", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1643", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1643", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0412", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1626", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/042", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 77272062