PATENT DOCUMENT

Publication Number: US-11705037-B1
Application Number: US-202117408133-A
Country: US
Kind Code: B1

Title: Foveated driving for power saving

Abstract:
In an embodiment, an electronic display includes an active area including a plurality of pixels arranged in columns and a plurality of source drivers driving image data to columns of pixels. The electronic display also includes a first plurality of switches selectively coupling respective source drivers of the plurality of source drivers to one or more columns. Selective coupling enables the respective source drivers to, at different times, drive the image data to: a single column; and multiple columns. In another embodiment, an electronic display includes a display panel configured to operate using a reference voltage received via a resistive path having a routing resistance, a reference voltage source outputting the reference voltage, and a feedback circuit sensing an electrical parameter of the resistive path and producing a compensation voltage that, when added to the reference voltage, causes the reference voltage to remain substantially constant at the display panel.

Claims:
What is claimed is: 
     
       1. An electronic display comprising:
 an active area comprising a plurality of pixels arranged in columns; and 
 a plurality of source drivers configured to drive image data to the columns of the plurality of pixels, wherein a first plurality of switches are configured to selectively couple respective source drivers of the plurality of source drivers to one or more respective columns of the columns of pixels, wherein the image data comprises foveated image data corresponding to a foveated region and a first peripheral region directly adjacent to the foveated region, and wherein:
 a first subset of source drivers of the plurality of source drivers are configurable by the first plurality of switches to respectively drive one column each in the foveated region; and 
 a second subset of source drivers of the plurality of source drivers are configurable by the first plurality of switches to respectively drive at least two columns each in the first peripheral region. 
 
 
     
     
       2. The electronic display of  claim 1 , wherein the foveated image data comprises a second peripheral region directly adjacent to the first peripheral region, and wherein a third subset of source drivers of the plurality of source drivers are configurable by the first plurality of switches to respectively drive at least three columns each in the second peripheral region. 
     
     
       3. The electronic display of  claim 1 , wherein the first plurality of switches are configurable to couple a first source driver of the plurality of source drivers to one column in a first state and two columns in a second state. 
     
     
       4. The electronic display of  claim 3 , wherein the first plurality of switches are configurable to couple the first source driver of the plurality of source drivers to four columns in a third state. 
     
     
       5. The electronic display of  claim 1 , wherein the first plurality of switches are configured to selectively couple the respective source drivers of the plurality of source drivers to the one or more respective columns to enable the respective source drivers to, at different times:
 drive the image data to a single column; 
 drive the image data to multiple columns; and 
 not drive the image data to any column. 
 
     
     
       6. The electronic display of  claim 1 , comprising a second plurality of switches configured to selectively route the image data to different source drivers of the plurality of source drivers. 
     
     
       7. The electronic display of  claim 1 , comprising a circuit component configured to supply a control signal, wherein the control signal is configured to control operation of the first plurality of switches. 
     
     
       8. The electronic display of  claim 7 , wherein:
 the control signal is a bit string; and 
 the circuit component is configured to supply the control signal to the first plurality of switches. 
 
     
     
       9. The electronic display of  claim 7 , wherein the circuit component is configured to determine at least one source driver of the plurality of source drivers is defective. 
     
     
       10. A method comprising:
 receiving an input about a gaze of a user on an active area, wherein the input includes at least a location of the gaze on the active area and wherein the active area comprises a plurality of pixels arranged in columns; 
 in response to receiving the input:
 determining a first luminance level of a foveated area about the location of the gaze; 
 determining a plurality of source drivers associated with the foveated area, wherein the plurality of source drivers are configured to drive image data to columns of pixels associated with the foveated area; and 
 coupling respective source drivers of the plurality of source drivers to one or more columns based on the first luminance level. 
 
 
     
     
       11. The method of  claim 10 , comprising:
 determining a second luminance level of the foveated area; and 
 coupling respective source drivers of the plurality of source drivers to two or more columns based on the second luminance level. 
 
     
     
       12. The method of  claim 10 , comprising:
 in response to receiving the input:
 determining a second luminance level of a second foveated area; 
 determining a second plurality of source drivers associated with the second foveated area, wherein the second plurality of source drivers are configured to drive image data to columns of pixels associated with the second foveated area; and 
 coupling respective source drivers of the second plurality of source drivers to two or more columns based on the second luminance level. 
 
 
     
     
       13. The method of  claim 12 , in response to receiving the input:
 determining a third luminance level of a third foveated area; 
 determining a third plurality of source drivers associated with the third foveated area, wherein the third plurality of source drivers are configured to drive image data to columns of pixels associated with the third foveated area; and 
 coupling respective source drivers of the third plurality of source drivers to three or more columns based on the third luminance level. 
 
     
     
       14. An electronic device, comprising:
 a gaze tracker configured to track a gaze of a user; and 
 an electronic display comprising:
 an active area comprising a plurality of pixels arranged in columns; 
 a source driver configured to drive image data to columns of pixels; 
 a first plurality of switches configured to selectively couple the source driver to one or more columns; and 
 a circuit component comprising a decode block configured to receive the image data, wherein the circuit component is configured to supply a control signal based on the gaze of the user to control operation of the first plurality of switches to couple the source driver, at different times, to:
 a single column; and 
 multiple columns. 
 
 
 
     
     
       15. The electronic device of  claim 14 , comprising a first switch configured to couple the source driver to the first plurality of switches. 
     
     
       16. The electronic device of  claim 15 , wherein the circuit component is configured to supply a second control signal to control operation of the first switch. 
     
     
       17. The electronic device of  claim 15 , comprising a second circuit component configured to supply a second control signal to control operation of the first switch. 
     
     
       18. The electronic device of  claim 15 , wherein the decode block is configured to decode the image data and supply the control signal based on the image data. 
     
     
       19. The electronic device of  claim 14 , wherein the gaze tracker is configured to track the gaze of the user based on the image data. 
     
     
       20. The electronic device of  claim 14 , wherein the gaze tracker is configured to track the gaze of the user based on a saliency analysis of the image data.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a non-provisional application claiming priority to U.S. Provisional Application No. 63/083,704, entitled “FOVEATED DRIVING FOR POWER SAVING,” filed Sep. 25, 2020, which is hereby incorporated by reference in its entirety for all purposes. 
    
    
     SUMMARY 
     A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below. 
     The present disclosure relates to power saving techniques that can be used with foveated content, such as dynamically foveated content. Foveation refers to a technique in which some aspect of an image (e.g., an amount of detail, image quality, coloration, or brightness) is varied across displayed content based at least in part on a fixation point, such as a point or area within the content itself, a point or region of the content on which one or more eyes of a user are focused, or movement of the one or more eyes of the user. For example, the brightness level in various portions of the image can be varied depending on the fixation point. Indeed, in regions of the electronic display some distance beyond the fixation point, which are more likely to appear in a person&#39;s peripheral vision, the brightness may be lowered. In this way, foveation can reduce an amount of power used to display the content on the electronic display without being noticeable to the person viewing the electronic display. 
     In static foveation, various areas of an electronic display having different brightness levels each have a fixed size and location on the electronic display for each frame of content displayed to the user. In dynamic foveation, the various areas at different brightness levels may change between two or more images based at least in part on the gaze of the viewer. For example, as the eyes of the user move across the electronic display from a top left corner to a bottom right corner, the high brightness level portion of the electronic display also moves from the top left corner to the bottom right corner of the display. For content that uses multiple images, such as videos and video games, the content may be presented to the viewer by displaying the images in rapid succession. The high brightness and lower brightness portions of the electronic display in which the content is displayed may change between frames. 
     For dynamic foveation, an eye tracking system is used to determine a focal point of the eyes of the user on the electronic display. That is, a continuous input from the eye tracking system is provided to a foveation system and used to determine the size and location of the high brightness level area on the electronic display. If the eye tracking system detects movement of the gaze of the user, the foveation system may cause display artifacts to be visible or perceived by the user which negatively affect the experience of the user. The artifacts may include low luminance levels at the focal point of the eyes of the user, intermittent switching between high luminance levels and low luminance levels due to sudden movement of the foveated areas of the display, and flashing resulting from sudden luminance level changes at various areas of the display. Foveation errors (e.g., temporal flashing) on the electronic display may be visible to the user and may deteriorate the experience of the user looking at the electronic display. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings described below. 
         FIG.  1    is a block diagram of an electronic device with an electronic display, according to an embodiment; 
         FIG.  2    is a perspective view of a notebook computer representing an embodiment of the electronic device of  FIG.  1   ; 
         FIG.  3    is a front view of a hand-held device representing another embodiment of the electronic device of  FIG.  1   ; 
         FIG.  4    is a front view of another hand-held device representing another embodiment of the electronic device of  FIG.  1   ; 
         FIG.  5    is a front view of a desktop computer representing another embodiment of the electronic device of  FIG.  1   ; 
         FIG.  6    is a perspective view of a wearable electronic device representing another embodiment of the electronic device of  FIG.  1   ; 
         FIG.  7    is a diagram of the display of  FIG.  1    using static foveation, according to an embodiment; 
         FIG.  8    is a diagram of the display of  FIG.  1    using dynamic foveation, according to an embodiment; 
         FIG.  9    is a diagram of the display of  FIG.  1    including foveated source drivers, according to an embodiment; 
         FIG.  10    is a schematic diagram of circuit components for a foveated display, according to an embodiment; 
         FIG.  11    is a schematic diagram of circuit components including a decode block for a foveated display, according to an embodiment; 
         FIG.  12    is a schematic diagram of circuit components including a decode block for controlling operation of source drivers for a foveated display, according to an embodiment; 
         FIG.  13    is a schematic diagram of circuit components for compensating voltage for an electronic display using dynamic foveation, according to an embodiment; 
         FIG.  14    is a set of graphs displaying a current and voltages for the circuit components of  FIG.  13   , according to an embodiment; 
         FIG.  15    is a schematic diagram of circuit components for supplying a voltage drop to an electronic display, according to an embodiment; and 
         FIG.  16    is a schematic diagram of circuit components for reducing power consumption for an electronic display, according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS 
     One or more specific embodiments will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
       FIG.  1    illustrates a block diagram of an electronic device  10  that may provide power saving techniques for a foveated display. As described in more detail below, the electronic device  10  may represent any suitable electronic device, such as a computer, a mobile phone, a portable media device, a tablet, a television, a virtual-reality headset, a vehicle dashboard, or the like. The electronic device  10  may represent, for example, a notebook computer  10 A as depicted in  FIG.  2   , a handheld device  10 B as depicted in  FIG.  3   , a handheld device  10 C as depicted in  FIG.  4   , a desktop computer  10 D as depicted in  FIG.  5   , a wearable electronic device  10 E as depicted in  FIG.  6   , or any suitable similar device with a display. 
     The electronic device  10  shown in  FIG.  1    may include, for example, a processor core complex  12 , a memory  14 , a storage device  16 , an electronic display  18 , input structures  22 , an input/output (I/O) interface  24 , a network interface  26 , a power source  29 , and an eye tracker  32 . The electronic device  10  may include image processing circuitry  30 . The image processing circuitry  30  may prepare image data (e.g., pixel data) from the processor core complex  12  for display on the electronic display  18 . 
     Although the image processing circuitry  30  is shown as a component within the processor core complex  12 , the image processing circuitry  30  may represent any suitable hardware and/or software that may occur between the initial creation of the image data and its preparation for display on the electronic display  18 . Thus, the image processing circuitry  30  may be located wholly or partly in the processor core complex  12 , wholly or partly as a separate component between the processor core complex  12  and the electronic display  18 , or wholly or partly as a component of the electronic display  18 . 
     The various components of the electronic device  10  may include hardware elements (including circuitry), software elements (including machine-executable instructions stored on a tangible, non-transitory medium, such as the local memory  14  or the storage device  16 , or a combination of both hardware and software elements. It should be noted that  FIG.  1    is merely one example of a particular implementation and is intended to illustrate the types of components that may be present in the electronic device  10 . Indeed, the various components illustrated in  FIG.  1    may be combined into fewer components or separated into additional components. For instance, the local memory  14  and the storage device  16  may be included in a single component. 
     The processor core complex  12  may perform a variety of operations of the electronic device  10 , such as generating image data to be displayed on the electronic display  18  and performing dynamic foveation of the content to be displayed on the electronic display  18 . The processor core complex  12  may include any suitable data processing circuitry to perform these operations, such as one or more microprocessors, one or more application specific processors (ASICs), or one or more programmable logic devices (PLDs). In some cases, the processor core complex  12  may execute programs or instructions (e.g., an operating system or application) stored on a suitable storage apparatus, such as the local memory  14  and/or the storage device  16 . 
     The memory  14  and the storage device  16  may also store data to be processed by the processor core complex  12 . That is, the memory  14  and/or the storage device  16  may include random access memory (RAM), read only memory (ROM), rewritable non-volatile memory such as flash memory, hard drives, optical discs, or the like. 
     The electronic display  18  may be a self-emissive display, such as an organic light emitting diode (OLED) display, an LED display, or μLED display or may be a liquid crystal display (LCD) illuminated by a backlight. In some embodiments, the electronic display  18  may include a touch screen, which may allow users to interact with a user interface of the electronic device  10 . Additionally, the electronic display  18  may show foveated content. 
     The electronic display  18  may display various types of content. For example, the content may include a graphical user interface (GUI) for an operating system or an application interface, still images, video, or any combination thereof. The processor core complex  12  may supply or modify at least some of the content to be displayed. 
     The input structures  22  of the electronic device  10  may enable a user to interact with the electronic device  10  (e.g., pressing a button or icon to increase or decrease a volume level). The I/O interface  24  and the network interface  26  may enable the electronic device  10  to interface with various other electronic devices. The power source  29  may include any suitable source of power, such as a rechargeable lithium polymer (Li-poly) battery and/or an alternating current (AC) power converter. 
     The network interface  26  may include, for example, interfaces for a personal area network (PAN), such as a Bluetooth network, a local area network (LAN) or wireless local area network (WLAN), such as an 802.11x Wi-Fi network, and/or a wide area network (WAN), such as a cellular network. The network interface  26  may also include interfaces for, for example, broadband fixed wireless access networks (WiMAX), mobile broadband Wireless networks (mobile WiMAX), asynchronous digital subscriber lines (e.g., ADSL, VDSL), digital video broadcasting-terrestrial (DVB-T) and its extension DVB Handheld (DVB-H), ultra-wideband (UWB), alternating current (AC) power lines, and so forth. 
     The eye tracker  32  may measure positions and movement of one or both eyes of a person viewing the electronic display  18  of the electronic device  10 . For instance, the eye tracker  32  may be a camera that records the movement of a viewer&#39;s eye(s) as the viewer looks at the electronic display  18 . However, several different practices may be employed to track a viewer&#39;s eye movements. For example, different types of infrared/near infrared eye tracking techniques such as bright-pupil tracking and dark-pupil tracking may be used. In these types of eye tracking, infrared or near infrared light is reflected off of one or both of the eyes of the viewer to create corneal reflections. 
     A vector between the center of the pupil of the eye and the corneal reflections may be used to determine a point on the electronic display  18  at which the viewer is looking. Moreover, as discussed below, varying portions of the electronic display  18  may be used to show content in relatively higher and lower luminance level portions based at least in part on the point of the electronic display  18  at which the viewer is looking. 
     As will be described in more detail herein, the image processing circuitry  30  may perform particular image processing adjustments to counteract artifacts that may be observed when the eye tracker  32  tracks eye movement during foveation. For example, foveated areas rendered on the electronic display  18  may be dynamically adjusted (e.g., by size and/or position). 
     As discussed above, the electronic device  10  may be a computer, a portable electronic device, a wearable electronic device, or other type of electronic device. Example computers may include generally portable computers (such as laptop, notebook, and tablet computers) as well as computers that are generally used in one place (such as conventional desktop computers, workstations, and/or servers). In certain embodiments, the electronic device  10  in the form of a computer may be a model of a MacBook®, MacBook® Pro, MacBook Air®, iMac®, Mac® mini, or Mac Pro® available from Apple Inc. of Cupertino, Calif. 
     By way of example, the electronic device  10  depicted in  FIG.  2    is a notebook computer  10 A, in accordance with one embodiment of the present disclosure. The computer  10 A includes a housing or enclosure  36 , an electronic display  18 , input structures  22 , and ports of an I/O interface, such as the I/O interface  24  discussed with respect to  FIG.  1   . In one embodiment, a user of the computer  10 A may use the input structures  22  (such as a keyboard and/or touchpad) to interact with the computer  10 A, such as to start, control, or operate a GUI or applications running on the computer  10 A. For example, a keyboard and/or touchpad may allow the user to navigate a user interface or application interface displayed on the electronic display  18 . Additionally, the computer  10 A may include an eye tracker  32 , such as a camera. 
       FIG.  3    depicts a front view of a handheld device  10 B, which represents one embodiment of the electronic device  10 . The handheld device  10 B may represent, for example, a portable phone, a media player, a personal data organizer, a handheld game platform, or any combination of such devices. By way of example, the handheld device  10 B may be a model of an iPod® or iPhone® available from Apple Inc. The handheld device  10 B includes an enclosure  36  to protect interior components from physical damage and to shield the interior components from electromagnetic interference. The enclosure  36  may surround the electronic display  18 . The I/O interfaces  24  may be formed through the enclosure  36  and may include, for example, an I/O port for a hardwired connection for charging and/or content manipulation using a standard connector and protocol, such as the Lightning connector provided by Apple Inc., a universal serial bus (USB), or other similar connector and protocol. Moreover, the handheld device  10 B may include an eye tracker  32 . 
     The user input structures  22 , in combination with the electronic display  18 , may allow a user to control the handheld device  10 B. For example, the input structures  22  may activate or deactivate the handheld device  10 B, navigate a user interface to a home screen or a user-configurable application screen, and/or activate a voice-recognition feature of the handheld device  10 B. Other input structures  22  may provide volume control, or toggle between vibrate and ring modes. The input structures  22  may also include a microphone to obtain a voice of the user for various voice-related features, and a speaker to enable audio playback and/or certain capabilities of the handheld device  10 B. The input structures  22  may also include a headphone input to provide a connection to external speakers and/or headphones. 
       FIG.  4    depicts a front view of another handheld device  10 C, which represents another embodiment of the electronic device  10  discussed with respect to  FIG.  1   . The handheld device  10 C may represent, for example, a tablet computer or portable computing device. By way of example, the handheld device  10 C may be a tablet-sized embodiment of the electronic device  10 , which may be, for example, a model of an iPad® available from Apple Inc. The various components of the handheld device  10 C may be similar to the components of the handheld device  10 B discussed with respect to the  FIG.  3   . The handheld device  10 C may include an eye tracker  32 . 
       FIG.  5    depicts a computer  10 D which represents another embodiment of the electronic device  10  discussed with respect to  FIG.  1   . The computer  10 D may be any computer, such as a desktop computer, a server, or a notebook computer, but may also be a standalone media player or video gaming machine. By way of example, the computer  10 D may be an iMac®, a MacBook®, or other similar device by Apple Inc. It should be noted that the computer  10 D may also represent a personal computer (PC) by another manufacturer. The enclosure  36  of the computer  10 D may be provided to protect and enclose internal components of the computer  10 D, such as the electronic display  18 . In certain embodiments, a user of the computer  10 D may interact with the computer  10 D using various peripheral input devices, such as input structures  22 A and  22 B (e.g., keyboard and mouse), which may connect to the computer  10 D. Furthermore, the computer  10 D may include an eye tracker  32 . 
       FIG.  6    depicts a wearable electronic device  10 E representing another embodiment of the electronic device  10  discussed with respect to  FIG.  1   . The wearable electronic device  10 E is configured to operate using techniques described herein. By way of example, the wearable electronic device  10 E may be virtual reality glasses. Additionally or alternatively, the wearable electronic device  10 E may be or include other wearable electronic devices such as augmented reality glasses. 
     The electronic display  18  of the wearable electronic device  10 E may be visible to a user when the electronic device  10 E is worn by the user. Additionally, while the user is wearing the wearable electronic device  10 E, an eye tracker (not shown) of the wearable electronic device  10 E may track the movement of one or both of the eyes of the user. In some instances, the handheld device  10 B discussed with respect to  FIG.  3    may be used in the wearable electronic device  10 E. For example, a portion  37  of a headset  38  of the wearable electronic device  10 E may allow a user to secure the handheld device  10 B therein and use the handheld device  10 B to view virtual reality content. 
     The electronic display  18  of the electronic device  10  may show images or frames of content such as photographs, videos, and video games in a foveated manner. Foveation refers to a technique in which an amount of detail, resolution, image quality, or brightness is varied across an image based at least in part on a fixation point, such as a point or area within the image itself, a point or region of the image on which a viewer&#39;s eyes are focused, or based at least in part on the gaze movement of the viewer&#39;s eyes. More specifically, the brightness can be varied by using different luminance levels in various portions of an image. For instance, in a first portion of the electronic display  18 , one luminance level may be used to display one portion of an image, while a lower or higher luminance level may be used for a second portion of the image on the electronic display  18 . The second portion of the electronic display  18  may be in a different area of the display  18  than the first area or may be located within the first area. 
     In some embodiments, the change in brightness or luminance level may be a gradual (i.e., smooth) transition from a central portion having a high luminance level to a peripheral edge of the foveated area. That is, for example, the luminance level of the foveated region may have a central portion with a high luminance. A luminance level of an outer portion of the foveated region may gradually decrease from an edge of the central region to an edge of the outer portion. 
       FIG.  7    is a diagram  60  representative of the electronic display  18  using static foveation. In static foveation, a size and/or a location of the various resolution areas of the electronic display  18  may be fixed. As shown, the electronic display  18  includes a higher luminance level area  64 , a medium luminance level area  66 , and a lower luminance level area  68  fixed about a centerpoint  62  of the display  18 . Application of the foveation techniques described herein may adjust (e.g., increase and/or decrease) one or more luminance levels of one or more areas of the display  18  relative to a defined luminance level associated with the respective area of the display  18 . A defined luminance level associated with each of the areas  64 ,  66 ,  68  may be a luminance level associated with image content before application of foveation techniques. In one particular example, the defined luminance level of the areas  64 ,  66 , and  68  may be a maximum luminance of the display (e.g., all white pixels at maximum brightness) if foveation were not used. With foveation, the adjusted luminance of the area  64  may be 100 percent of defined luminance level, the adjusted luminance of the area  66  may be eighty percent of the defined luminance level, and the luminance level of the area  68  may be sixty percent of the defined luminance level of the display  18 . 
     To reiterate, the adjusted luminance levels of the areas  64 ,  66 , and  68  are relative to the defined luminance levels of the areas  64 ,  66 , and  68 , respectively. The defined luminance thus may change depending on the content of the image data. The medium luminance level area  66  may have a lower luminance level than a defined luminance level of the same area. Similarly, the luminance level of the lower luminance level area  68  may be lower than the defined luminance level of the same area. Finally, the luminance level of the higher luminance level area  64  may be the same, lower, or even higher than the defined luminance level of the same area. In certain embodiments, the adjusted luminance level of an area further from the centerpoint  62  may be adjusted more (e.g., further reduced) than an adjusted luminance level of an area closer to the centerpoint  62 . Additionally or alternatively, the adjusted luminance level of an area further from the centerpoint  62  may be adjusted less (e.g., reduced to a lesser extent) than an adjusted luminance level of an area closer to the centerpoint  62 . 
     As one example, an adjusted luminance level of the lower luminance level area  68  may be between forty to sixty percent of a defined luminance level of an original image brightness associated with the area  68 . That is, the adjusted luminance level may be between forty to sixty percent of the defined luminance level (e.g., sixty percent of the maximum luminance level) of the display, as described in the example above. An adjusted luminance level of the medium luminance level area  66  may be between sixty to eighty percent of a defined luminance level of an original image brightness associated with the area  66  and a luminance level of the higher luminance level area  64  may be between eighty to one hundred percent of a defined luminance level of an original image brightness associated with the area  64 . As illustrated in  FIG.  7   , three areas  64 ,  66 ,  68  may be formed from concentric circles about the centerpoint  62 . While three areas are illustrated in  FIG.  7   , it should be understood that there may be two or more areas (e.g., a higher luminance level area and a lower luminance level area) of the electronic display  18 . Moreover, in some examples, the luminance may be adjusted according to any suitable function that reduces the brightness of image data based at least in part on the distance of image pixels from the centerpoint  62 . 
     As described above, electronic displays such as the electronic display  18  may also use dynamic foveation. In dynamic foveation, the areas of the electronic display  18  at which the various luminance levels are used may change between two or more images based at least in part on the focal point of the eyes of the user. As an example, content that uses multiple images, such as videos and video games, may be presented to viewers by displaying the images in rapid succession. The portions of the electronic display  18  in which the content is displayed with a relatively high luminance level and a relatively low luminance level may change, for instance, based at least in part on data collected by the eye tracker  32  which indicates a focal point on the electronic display  18  of the eyes of the user. 
       FIG.  8    is a diagram  70  that illustrates the electronic display  18  using dynamic foveation. The diagram  70  includes a first frame  74  and a second frame  86  each having a higher luminance level area  76 , a medium luminance level area  78 , and a lower luminance level area  80 . The first frame  74  and the second frame  86  each may represent a different portion of a single content frame (e.g., a different portion of a single image) or each may represent a different content frame of consecutive content frames (e.g., content frames of a video). In some instances, transitional frames between these frames provide a smooth movement of the frames  74  and  86  corresponding to tracked movement  82  of the eyes of the user from a first location  72  associated with the first frame  74  and a second location  84  associated with the second frame  86 . The higher luminance level area  76 , the medium luminance level area  78 , and the lower luminance level area  80  each may correspond to the higher luminance level area  64 , the medium luminance level area  66 , and the lower luminance level area  68  discussed with respect to  FIG.  7   . 
     The frames  74  and  86  are in different locations on the electronic display  18  based at least in part on a focal point of the eyes of the user. During a transition from the first frame  74  to the second frame  86  (or when the focal point of the eyes of the user move from the first location  72  of the first frame  74  to the second location  84  of the second frame  86 ), the higher luminance level area  76  and medium luminance level area  78  are moved from near a bottom left corner of the electronic display  18  to a top right corner of the electronic display  18 . 
     A foveation system may reduce power and increase power savings by turning off circuit components of a display panel in one or more foveated areas. For example, a foveation system may receive an indication of a gaze from a gaze tracker and may determine corresponding portions of an electronic display which may be operated by a reduced number of circuit components.  FIG.  9    is a diagram  90  that illustrates the electronic display  18  using foveation techniques. The electronic display  18  may include a display panel having multiple display pixels arranged as an array or matrix defining multiple rows and columns. The electronic display  18  may include a low luminance level area  102 , a medium luminance level area  104 , and a high luminance level area  106 . The electronic display  18  may include any number of source drivers that may receive image data that indicates desired luminance of one or more display pixels for displaying an image frame, analyze the image data to determine timing data based at least in part on what display pixels the image data corresponds to, and transmit the timing data to a gate driver. Based at least in part on the timing data, the gate driver may then transmit gate activation signals to activate a row of display pixels. 
     When activated, luminance of a display pixel may be adjusted by amplified image data received via data lines  100 . The source drivers may generate amplified image data by receiving the image data and amplifying voltage of the image data. The source drivers may then supply the amplified image data to the activated pixels. Based on received amplified image data, the display pixels may adjust a corresponding luminance using electrical power supplied from the power source  29 . In some embodiments, the electronic display  18  includes a first source driver amplifier  92 , a second source driver amplifier  94 , a third source driver amplifier  96 , and any number of inactive source driver amplifiers  98 . The first source driver amplifier  92  may be associated with any number of rows and/or columns of pixels in the low luminance level area  102 . The foveation system may receive an indication of a gaze from a gaze tracker and determine area  102  corresponds to a low luminance level area  102 . As a result, the foveation system may turn off any number of source driver amplifiers  98  associated with the low luminance level area  102  and may connect the first source driver amplifier  92  to data lines previously supplied image data by the now inactive source driver amplifiers  98 . For example, the first source driver amplifier  92  may be connected to four data lines  100  and may supply amplified image data to display pixels associated with the four data lines  100 . 
     The second source driver amplifier  94  may be associated with any number of rows and/or columns of pixels in the medium luminance level area  104 . The foveation system may receive an indication of a gaze from a gaze tracker and determine area  104  corresponds to a medium luminance level area  104 . As a result, the foveation system may turn off any number of source driver amplifiers  98  associated with the medium luminance level area  104  and may connect the second source driver amplifier  94  to data lines previously supplied image data by the now inactive source driver amplifiers  98 . For example, the second source driver amplifier  94  may be connected to two data lines  100  and may supply amplified image data to display pixels associated with the two data lines  100 . The third source driver amplifier  96  may be connected to a single row and/or column of pixels in the high luminance level area  106 . The foveation system may receive an indication of a gaze from a gaze tracker and determine area  106  corresponds to a high luminance level area  106 . As a result, the foveation system may leave on all source driver amplifiers in the high luminance level area  106 . For example, the third source driver amplifier  96  may be connected to a single data line  100  and may supply amplified image data to display pixels associated with the single data line  100 . While the source driver amplifiers in  FIG.  9    illustrate connections to one, two, or four data lines, any number of data lines may be connected a source driver amplifier according to the foveated area associated with the source driver amplifier and the data lines. 
     A foveation system may receive an indication of movement associated with a gaze from a gaze tracker and may adjust one or more foveated areas, as described above. If the eye tracking system detects movement of the gaze of the user, the foveation system may cause display artifacts to be visible or perceived by the user which negatively affect the experience of the user. The artifacts may include low luminance levels at the focal point of the eyes of the user, intermittent switching between high luminance levels and low luminance levels due to sudden movement of the foveated areas of the display, and flashing resulting from sudden luminance level changes at various areas of the display. To prevent artifacts levels from being visible and deteriorating an experience of the user, techniques described herein provide compensation to image data. 
       FIG.  10    illustrates a schematic diagram  110  of circuit components for a foveated display, according to an embodiment of the present disclosure. The schematic diagram  110  may include any number of source drivers  124  and each source driver may include a red component  116 , a blue component  118 , and a green component  120 . A first flip flop  112  controls operation of a set of switches  122  (e.g., switches  126 ,  128 ,  130 ,  132 ) to determine one or more source drivers to supply power to one or more rows of pixels in an electronic display  18 . For example, the first flip flop  112  may supply a control signal  114  based on a logic table, such as Table 1 below: 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Bit String 
                 Source Driver Mode 
               
               
                   
                   
               
             
            
               
                   
                 00 
                 n/a 
               
               
                   
                 01 
                 1x 
               
               
                   
                 10 
                 2x 
               
               
                   
                 11 
                 4x 
               
               
                   
                   
               
            
           
         
       
     
     The control signal  114  may be a bit string for determining an operational mode for any number of source drivers. For example, in a 01 bit string of the control signal  114 , the first switch  126  may close which connects two rows of pixels of the display  18  to a single source driver, such as source driver  124 , as described above with respect to  FIG.  9   . As another example, a 11 bit string of the control signal  114  may close switches  126 ,  128 , and  130  to connect four rows of pixels of the display panel to the source driver  124 . While the above discussion refers to the source driver  124 , any suitable switches may be opened or closed to connect any number of source drivers to any number of rows of pixels of the display  18 . A second flip flop  134  may control the operation of a second set of switches, such as switch  136  that determine which source driver(s) to connect to the display  18 . For example, the second flip flop  134  may supply a control signal to operate the switch  136  and connect the source driver  124  to the display  18 . 
       FIG.  11    illustrates a schematic diagram  140  of circuit components for a foveated display, according to an embodiment of the present disclosure. A decode block  142  may supply a control signal to control operation of a set of switches, such as switch  136  that determine which source driver(s) to connect to the display  18 . For example, the set of switches may couple any subset (e.g., 1, 2, all) of the source drivers to the display  18 . The decode block  142  may decode image data in any suitable way. For example, the decode block  142  may supply a control signal to operate the switch  136  and connect the source driver  124  to the display  18 . The first flip flop  112  may supply a control signal  114  based on a logic table, such as Table 2 below: 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                 Bit String 
                 Source Driver Mode 
               
               
                   
                   
               
             
            
               
                   
                 00 
                 1x 
               
               
                   
                 01 
                 1x 
               
               
                   
                 10 
                 2x 
               
               
                   
                 11 
                 4x 
               
               
                   
                   
               
            
           
         
       
     
     In certain embodiments, the decode block  142  may receive the control signal  114  and may control operation of the set of switches to determine which source driver(s) to connect to the display  18  based on the control signal  114 . For example, the decode block  142  may determine at least one of the source drivers is defective (e.g., inoperative) and may bypass the defective source driver. 
       FIG.  12    illustrates a schematic diagram  150  of circuit components for a foveated display, according to an embodiment of the present disclosure. A decode block  152  may supply a first control signal to control operation of a first set of switches, such as switch  136  that determine which source driver(s) to connect to the display  18 . In some embodiments, the decode block  152  may supply a first control signal based on a luminance level for a foveated area of the display  18 . For example, the decode block  152  may supply a control signal to operate the switch  136  and connect the source driver  124  to the display  18  to drive one or more rows of pixels of the display  18 . In some embodiments, the decode block  152  may supply a control signal  114  to control operation of a second set of switches  122  (e.g., switches  126 ,  128 ,  130 ,  132 ). The decode block  152  may decode image data in any suitable way. For example, the decode block  152  may supply a control signal  114  based on a logic table, such as Table 3 below: 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 3 
               
               
                   
                   
               
               
                   
                 Bit String 
                 Source Driver Mode 
               
               
                   
                   
               
             
            
               
                   
                 000 
                 1x 
               
               
                   
                 001 
                 1x 
               
               
                   
                 010 
                 1x 
               
               
                   
                 01l 
                 1x 
               
               
                   
                 100 
                 1x 
               
               
                   
                 101 
                 n/a 
               
               
                   
                 110 
                 2x 
               
               
                   
                 111 
                 4x 
               
               
                   
                   
               
            
           
         
       
     
     In certain embodiments, the decode block  152  may receive the control signal  114  and may control operation of the set of switches to determine which source driver(s) to connect to the display  18  based on the control signal  114 . For example, the decode block  152  may determine at least one of the source drivers is defective and may bypass the defective source driver. 
       FIG.  13    illustrates a schematic diagram of a sensing and compensation circuit  160  for compensating voltage for an electronic display using dynamic foveation, such as the electronic display  18  discussed above, according to an embodiment of the present disclosure. The sensing and compensation circuit  160  may be embodied on a source driver. The electronic display  18  may include a display panel having multiple display pixels arranged as an array or matrix defining multiple rows and columns. In some embodiments, the display panel may have a characteristic panel resistance. The sensing and compensation circuit  160  may determine the characteristic panel resistance for associated with a corresponding display panel. For example, the characteristic panel resistance may be measured after fabrication of the display panel. In certain embodiments, the sensing and compensation circuit  160  may include a routing resistance  166  associated with the components and transmission lines. The characteristic panel resistance and the routing resistance  166  may cause a voltage drop as the foveation system adjusts current supplied based on receiving an indication of movement of a gaze from an eye tracker. For example, the eye tracker may provide a direction of movement of the gaze. As a result of the voltage drop, the display pixels may display differing luminance levels and affect an experience of a user. The sensing and compensation circuit  160  may sense one or more parameters from the display panel, such as an emission current  174 . For example, the sensing and compensation circuit  160  may include feedback circuit  172  including a current sensing component  168 . In some embodiments, the sensing component  168  may be a resistor having an associated resistance and may be significantly similar to the routing resistance  166  of the sensing and compensation circuit  160 . For example, the sensing component  168  may have a resistance within one percent, within one tenth of a percent, within one hundredth of a percent, within one thousandth of a percent, and so forth. In certain embodiments, the sensing component  168  may have a resistance significantly smaller than the routing resistance  166  of the sensing and compensation circuit  160 . The sensing component  168  may supply a compensation voltage to a summer  162  where it is combined with a reference voltage output from a reference voltage source. The compensated reference voltage may be delivered to a reference buffer  164  for delivery to the display panel. Hence, the compensated reference voltage may reduce or eliminate the transient effects from the shifting current in response to the indication of movement. 
     In certain embodiments, the feedback circuit  172  may include a filter component  170 . The filter component  170  may prevent the compensated reference voltage from changing too quickly in response to the compensation voltage. For example, the filter component  170  may include a one kilohertz filter and may filter out high frequency (e.g., above one kilohertz) spikes in the compensation voltage. 
       FIG.  14    illustrates a set of graphs of the sensing and compensation circuit  160  in  FIG.  13   , according to an embodiment of the present disclosure. In graph  180 , a first line  182  indicates an emission current measured by the sensing and compensation circuit. The first line  182  may begin at time zero where the measured current is zero and may increase in response to the foveation system receiving an indication of movement associated with a gaze. The graph  184  corresponds to a near end area of the display panel. The graph  184  illustrates a line  186  indicating an uncompensated reference voltage corresponding to a display panel without the sensing and compensation circuit  160 . As illustrated, the line  186  drops from a first voltage value (e.g., between two to five volts) to a second voltage value (e.g., between two to five volts) in response to the changing emission current depicted in graph  180 . As such, artifacts may be visible or may be perceived by the user which negatively affect the experience of the user. The line  188  indicates a compensated reference voltage corresponding to a display panel with a sensing and compensation circuit  160  having a sensing component  168  resistance equal to the routing resistance  166 . As shown, the line  188  stays relatively close to the initial value (e.g., within one percent, within one tenth of a percent, within one hundredth of a percent, and so forth) and differs from the initial value less than the uncompensated reference voltage in line  186  in response to the changing emission current depicted in graph  180 . The line  190  indicates a compensated reference voltage corresponding to a display panel with a sensing and compensation circuit  160  having a sensing component  168  resistance equal to a sum of the routing resistance  166  and an associated resistance of the display panel (e.g., about 0.1 Ohms). As shown, the line  190  increases slightly above the initial value (e.g., between two to five volts) in response to the changing emission current depicted in graph  180 . As such, the compensated reference voltage delivered to the display panel may reduce or may eliminate artifacts from being visible and deteriorating an experience of a user. 
     The graph  192  corresponds to a far end area of the display panel. The graph  192  illustrates a line  194  indicating an uncompensated reference voltage corresponding to a display panel without the sensing and compensation circuit  160 . As illustrated, the line  194  drops from a first voltage value (e.g., between two to five volts) to a second voltage value (e.g, between two to five volts) in response to the changing emission current depicted in graph  180 . As such, artifacts may be visible or may be perceived by the user which negatively affect the experience of the user. The line  196  indicates a compensated reference voltage corresponding to a display panel with a sensing and compensation circuit  160  having a sensing component  168  resistance equal to the routing resistance  166 . As shown, the line  196  has a voltage drop (e.g., within one percent, within one tenth of a percent, within one hundredth of a percent, and so forth) and differs less than the uncompensated reference voltage in line  194  in response to the changing emission current depicted in graph  180 . The line  198  indicates a compensated reference voltage corresponding to a display panel with a sensing and compensation circuit  160  having a sensing component  168  resistance equal to a sum of the routing resistance  166  and an associated resistance of the display panel. As shown, the line  198  stays relatively close to the initial value (e.g., within one percent, within one tenth of a percent, within one hundredth of a percent, and so forth) in response to the changing emission current depicted in graph  180 . As such, the compensated reference voltage delivered to the display panel may reduce and/or may eliminate artifacts from being visible and deteriorating an experience of a user. 
       FIG.  15    is a schematic diagram  220  of circuit components for supplying a voltage drop to an electronic display, according to an embodiment. A voltage source  222  supplies a reference voltage, Vref, according to image data for displaying luminance levels at a display pixel of electronic display  18 . A first resistor  224  may have a resistance of N*R 0 , where N may be any suitable number, and a second resistor  230  may have a resistance of R 0 . The voltage drop across the second resistor  230  may be equivalent to the reference voltage supplied by the voltage source  222 . A first transistor  226  and a second transistor  228  may have a relationship of 1 to N based on a size of the first transistor  226  and the second transistor  228 . A current source  234  may produce a constant load current for differing load resistances. An amplifier  232  may be supplied the reference voltage, Vref. 
       FIG.  16    is a schematic diagram  240  of circuit components for reducing power consumption when a load is off, according to an embodiment of the present disclosure. The schematic diagram  240  may include a first current source  248  and a second current source  250 . In some embodiments, the second current source  250  may produce a load current greater than the first current source  248  (e.g., five hundred times greater, one thousand times greater, and so forth). A first transistor  252  may have a lower doping concentration level than a second transistor  254  (e.g., five hundred times smaller, one thousand times smaller, and so forth. In certain embodiments, the ratio of doping concentration levels between the first transistor  252  and the second transistor  254  may be equal to a ratio between the load current from the first current source  248  and the load current from the second current source  250 . An input voltage, Vin, may be supplied to an amplifier  242 . A first switch  244  and a second switch  246  may control feedback to the amplifier  242  based on an operational mode of an electronic display. For example, in normal operation when the electronic display is powered on, the first switch  244  may be open (as shown) and the second switch  246  may be closed. An output voltage, Vo, may be regulated by the feedback through the first switch  244  supplied to the amplifier  242 . When the load is powered down or turned off, second switch  246  may be open (as shown) and first switch  244  may be closed. 
     As may be appreciated, though the current embodiments refer to movement of the foveated areas toward the center of the display, movement of the foveated area toward other portions of the display could be performed in other embodiments. For example, based upon contextual (e.g., saliency) information of the images displayed on the display, it may be more likely that the focus of the eyes of the user will be at another part of the display (e.g., a more salient area of the display). A salient area of the display may be considered an area of interest based at least in part on the image content. The focal point of the eyes of the user may be drawn to the salient area of the display based at least in part on the content. 
     When a likely focus area is known, it may be prudent to default movement of the foveated areas toward that portion of the display rather than the center of the display. Thus, in an example where the images displayed have dynamic movement only in the upper right corner (i.e., other portions of the images in the display are still—this may be referred to as “saliency by the effect of movement”), the likely focal area may be the area where dynamic movement is being rendered. Accordingly, in this example the movement of the foveated areas may be toward the upper right corner (i.e., toward the dynamic movement being rendered). 
     The specific embodiments described above have been shown by way of example, and it should be understood that these embodiments may be susceptible to various modifications and alternative forms. It should be further understood that the claims are not intended to be limited to the particular forms disclosed, but rather to cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure. 
     The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function]. . . ” or “step for [perform]ing [a function]. . . ”, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f). 
     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.

Metadata:
Filing Date: 20210820
Publication Date: 20230718
Grant Date: 20230718
Priority Date: 20200925
Inventors: HAFIZ, OMAR
CAGDASER, BARIS
WETHERELL, JOHN T.
ZHAO, HAN
Assignee: APPLE INC
CPC Classifications: [{"code": "G09G3/20", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G2320/0233", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2320/0626", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/20", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G2320/0233", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2320/0626", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/20", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G2330/021", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/08", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/12", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2310/027", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2340/0407", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2354/00", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2310/0291", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 87163288