PATENT DOCUMENT

Publication Number: US-12200185-B1
Application Number: US-202217885455-A
Country: US
Kind Code: B1

Title: Ray tracing in a display

Abstract:
An electronic device may include a lenticular display. The lenticular display may have a lenticular lens film formed over an array of pixels. The display may include ray tracing circuitry that is configured to, using ray tracing, a three-dimensional image, and deflection measurements for the array of pixels, output a display calibration map that includes, for each pixel in the array of pixels, a corresponding location on a two-dimensional image. The display may also include pixel mapping circuitry configured to, using the display calibration map from the ray tracing circuitry, map the two-dimensional image to respective pixels on the array of pixels to obtain pixel data for the array of pixels.

Claims:
What is claimed is: 
     
       1. An electronic device comprising:
 a display that includes an array of pixels and a lenticular lens film formed over the array of pixels; 
 ray tracing circuitry configured to, using ray tracing, a three-dimensional image, and deflection measurements for the array of pixels, output a display calibration map that includes, for each pixel in the array of pixels, a corresponding location on a two-dimensional image; and 
 pixel mapping circuitry configured to, using the display calibration map from the ray tracing circuitry, map the two-dimensional image to respective pixels on the array of pixels to obtain pixel data for the array of pixels. 
 
     
     
       2. The electronic device defined in  claim 1 , wherein the lenticular lens film spreads light from the array of pixels in a horizontal direction. 
     
     
       3. The electronic device defined in  claim 2 , wherein each pixel in the array of pixels has a corresponding deflection measurement of the deflection measurements and wherein the deflection measurement for each pixel represents a horizontal deflection of light emitted by that pixel. 
     
     
       4. The electronic device defined in  claim 3 , wherein the ray tracing circuitry is configured to use the deflection measurement for a pixel to trace a ray in an opposite direction of the light emitted by that pixel. 
     
     
       5. The electronic device defined in  claim 4 , wherein the ray tracing circuitry is configured to determine where the ray in the opposite direction intersects a three-dimensional surface from the three-dimensional image. 
     
     
       6. The electronic device defined in  claim 1 , wherein the display operates at a frame rate and wherein the ray tracing circuitry is configured to output the display calibration map at a second frequency that is lower than the frame rate. 
     
     
       7. The electronic device defined in  claim 6 , wherein the frame rate is at least 50 times greater than the second frequency. 
     
     
       8. The electronic device defined in  claim 1 , further comprising:
 pre-mapping processing circuitry configured to process the two-dimensional image before the two-dimensional image is provided to the pixel mapping circuitry. 
 
     
     
       9. The electronic device defined in  claim 8 , wherein the pre-mapping processing circuitry is configured to dither the two-dimensional image. 
     
     
       10. The electronic device defined in  claim 9 , wherein the pre-mapping processing circuitry is configured to tone map the two-dimensional image. 
     
     
       11. The electronic device defined in  claim 10 , wherein the pre-mapping processing circuitry is configured to, after tone mapping, adjust the two-dimensional image based on an ambient light level. 
     
     
       12. The electronic device defined in  claim 11 , wherein the pre-mapping processing circuitry is configured to, after tone mapping, perform a white point calibration for the two-dimensional image. 
     
     
       13. The electronic device defined in  claim 12 , wherein the pre-mapping processing circuitry is configured to, before tone mapping, pre-process the two-dimensional image. 
     
     
       14. The electronic device defined in  claim 13 , wherein pre-processing the two-dimensional image comprises applying an anisotropic low-pass filter to the two-dimensional image. 
     
     
       15. The electronic device defined in  claim 1 , further comprising:
 post-mapping processing circuitry configured to process the pixel data for the array of pixels after the two-dimensional image is provided to the pixel mapping circuitry. 
 
     
     
       16. The electronic device defined in  claim 15 , wherein the post-mapping processing circuitry is configured to perform burn-in compensation on the pixel data. 
     
     
       17. The electronic device defined in  claim 16 , wherein the post-mapping processing circuitry is configured to selectively apply dimming factors to the pixel data. 
     
     
       18. The electronic device defined in  claim 17 , wherein the post-mapping processing circuitry is configured to convert the pixel data to voltage levels. 
     
     
       19. An electronic device comprising:
 one or more sensors that are configured to capture a two-dimensional image and a three-dimensional image; and 
 a display with an array of pixels overlapped by lenticular lenses, wherein the display is configured to:
 receive the three-dimensional image from the one or more sensors; 
 based on the three-dimensional image and deflection measurements for the array of pixels, use ray tracing to obtain a display calibration map that includes, for each pixel in the array of pixels, a corresponding location on the two-dimensional image; 
 using the display calibration map, map the two-dimensional image to respective pixels on the array of pixels to obtain pixel data for the array of pixels; and 
 display the pixel data for the array of pixels. 
 
 
     
     
       20. A method of operating an electronic device with at least one sensor and a display having an array of pixels overlapped by lenticular lenses, the method comprising:
 based on a three-dimensional image from the at least one sensor and deflection measurements for the array of pixels, using ray tracing to obtain a display calibration map that includes, for each pixel in the array of pixels, a corresponding location on a two-dimensional image; 
 using the display calibration map, mapping the two-dimensional image to respective pixels on the array of pixels to obtain pixel data for the array of pixels; and 
 displaying the pixel data for the array of pixels.

Description:
This application is a continuation-in-part of non-provisional patent application Ser. No. 17/348,281, filed Jun. 15, 2021, which claims the benefit of provisional patent application No. 63/064,321, filed Aug. 11, 2020, provisional patent application No. 63/064,330, filed Aug. 11, 2020, and provisional patent application No. 63/064,342, filed Aug. 11, 2020, which are hereby incorporated by reference herein in their entireties. 
    
    
     FIELD 
     This relates generally to electronic devices, and, more particularly, to electronic devices with displays. 
     BACKGROUND 
     Electronic devices often include displays. In some cases, displays may include lenticular lenses that enable the display to provide three-dimensional content to the viewer. The lenticular lenses may be formed over an array of pixels such as organic light-emitting diode pixels or liquid crystal display pixels. 
     SUMMARY 
     An electronic device may include a lenticular display. The lenticular display may have a lenticular lens film formed over an array of pixels. A plurality of lenticular lenses may extend across the length of the display. The lenticular lenses may be configured to enable stereoscopic viewing of the display such that a viewer perceives three-dimensional images. 
     The display may have a number of independently controllable viewing zones. Each viewing zone displays a respective two-dimensional image. Each eye of the viewer may receive a different one of the two-dimensional images, resulting in a perceived three-dimensional image. Control circuitry in the electronic device may use the captured images from the eye and/or head tracking system to determine which viewing zones are occupied by the viewer&#39;s eyes. 
     The electronic device may include display pipeline circuitry that generates and process content to be displayed on the lenticular display. Content generating circuitry may initially generate content that includes a plurality of two-dimensional images, each two-dimensional image corresponding to a respective viewing zone. 
     The two-dimensional images may be processed by per-view processing circuitry. Tone mapping circuitry may convert content luminance values to display luminance values. Ambient light adaptation circuitry and white point calibration circuitry may be used to adjust the display luminance values. Dithering circuitry may be used to dither the two-dimensional images. 
     Pixel mapping circuitry may be used to map the two-dimensional images to the array of pixels in the lenticular display. Each two-dimensional image may have a respective subset of pixels on the display, such that the two-dimensional images are blended together and displayed simultaneously. After pixel mapping, additional panel-level processing such as burn-in compensation and panel response compensation may be performed. 
     The display may include ray tracing circuitry that is configured to, using ray tracing, a three-dimensional image, and deflection measurements for the array of pixels, output a display calibration map that includes, for each pixel in the array of pixels, a corresponding location on a two-dimensional image. The display may also include pixel mapping circuitry configured to, using the display calibration map from the ray tracing circuitry, map the two-dimensional image to respective pixels on the array of pixels to obtain pixel data for the array of pixels. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a schematic diagram of an illustrative electronic device having a display in accordance with an embodiment. 
         FIG.  2    is a top view of an illustrative display in an electronic device in accordance with an embodiment. 
         FIG.  3    is a cross-sectional side view of an illustrative lenticular display that provides images to a viewer in accordance with an embodiment. 
         FIG.  4    is a cross-sectional side view of an illustrative lenticular display that provides images to two or more viewers in accordance with an embodiment. 
         FIG.  5    is a top view of an illustrative lenticular lens film showing the elongated shape of the lenticular lenses in accordance with an embodiment. 
         FIG.  6    is a diagram of an illustrative display that includes an eye and/or head tracking system that determines viewer eye position and control circuitry that updates the display based on the viewer eye position in accordance with an embodiment. 
         FIGS.  7 A- 7 C  are perspective views of illustrative three-dimensional content that may be displayed on different zones of the display of  FIG.  6    in accordance with an embodiment. 
         FIG.  8    is a schematic diagram of an illustrative lenticular display including display pipeline circuitry in accordance with an embodiment. 
         FIG.  9    is a schematic diagram of an illustrative lenticular display with display pipeline circuitry that includes both per-view processing circuitry and panel-level processing circuitry in accordance with an embodiment. 
         FIG.  10    is a flowchart of illustrative method steps for operating a lenticular display with display pipeline circuitry such as the display of  FIG.  9    in accordance with an embodiment. 
         FIG.  11    is a schematic diagram of an illustrative lenticular display with ray tracing circuitry in accordance with an embodiment. 
         FIG.  12    is a side view of an illustrative display showing how a deflection angle for a given pixel and ray tracing may be used to determine an intersection point on a three-dimensional surface in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     An illustrative electronic device of the type that may be provided with a display is shown in  FIG.  1   . Electronic device  10  may be a computing device such as a laptop computer, a computer monitor containing an embedded computer, a tablet computer, a cellular telephone, a media player, or other handheld or portable electronic device, a smaller device such as a wrist-watch device, a pendant device, a headphone or earpiece device, an augmented reality (AR) headset and/or virtual reality (VR) headset, a device embedded in eyeglasses or other equipment worn on a user&#39;s head, or other wearable or miniature device, a display, a computer display that contains an embedded computer, a computer display that does not contain an embedded computer, a gaming device, a navigation device, an embedded system such as a system in which electronic equipment with a display is mounted in a kiosk or automobile, or other electronic equipment. As shown in  FIG.  1   , electronic device  10  may have control circuitry  16 . Control circuitry  16  may include storage and processing circuitry for supporting the operation of device  10 . The storage and processing circuitry may include storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory configured to form a solid state drive), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in control circuitry  16  may be used to control the operation of device  10 . The processing circuitry may be based on one or more microprocessors, microcontrollers, digital signal processors, baseband processors, power management units, audio chips, application specific integrated circuits, etc. 
     To support communications between device  10  and external equipment, control circuitry  16  may communicate using communications circuitry  21 . Circuitry  21  may include antennas, radio-frequency transceiver circuitry, and other wireless communications circuitry and/or wired communications circuitry. Circuitry  21 , which may sometimes be referred to as control circuitry and/or control and communications circuitry, may support bidirectional wireless communications between device  10  and external equipment over a wireless link (e.g., circuitry  21  may include radio-frequency transceiver circuitry such as wireless local area network transceiver circuitry configured to support communications over a wireless local area network link, near-field communications transceiver circuitry configured to support communications over a near-field communications link, cellular telephone transceiver circuitry configured to support communications over a cellular telephone link, or transceiver circuitry configured to support communications over any other suitable wired or wireless communications link). Wireless communications may, for example, be supported over a Bluetooth® link, a WiFi® link, a 60 GHz link or other millimeter wave link, a cellular telephone link, or other wireless communications link. Device  10  may, if desired, include power circuits for transmitting and/or receiving wired and/or wireless power and may include batteries or other energy storage devices. For example, device  10  may include a coil and rectifier to receive wireless power that is provided to circuitry in device  10 . 
     Input-output circuitry in device  10  such as input-output devices  12  may be used to allow data to be supplied to device  10  and to allow data to be provided from device  10  to external devices. Input-output devices  12  may include buttons, joysticks, scrolling wheels, touch pads, key pads, keyboards, microphones, speakers, tone generators, vibrators, cameras, sensors, light-emitting diodes and other status indicators, data ports, and other electrical components. A user can control the operation of device  10  by supplying commands through input-output devices  12  and may receive status information and other output from device  10  using the output resources of input-output devices  12 . 
     Input-output devices  12  may include one or more displays such as display  14 . Display  14  may be a touch screen display that includes a touch sensor for gathering touch input from a user or display  14  may be insensitive to touch. A touch sensor for display  14  may be based on an array of capacitive touch sensor electrodes, acoustic touch sensor structures, resistive touch components, force-based touch sensor structures, a light-based touch sensor, or other suitable touch sensor arrangements. 
     Some electronic devices may include two displays. In one possible arrangement, a first display may be positioned on one side of the device and a second display may be positioned on a second, opposing side of the device. The first and second displays therefore may have a back-to-back arrangement. One or both of the displays may be curved. 
     Sensors in input-output devices  12  may include force sensors (e.g., strain gauges, capacitive force sensors, resistive force sensors, etc.), audio sensors such as microphones, touch and/or proximity sensors such as capacitive sensors (e.g., a two-dimensional capacitive touch sensor integrated into display  14 , a two-dimensional capacitive touch sensor overlapping display  14 , and/or a touch sensor that forms a button, trackpad, or other input device not associated with a display), and other sensors. If desired, sensors in input-output devices  12  may include optical sensors such as optical sensors that emit and detect light, ultrasonic sensors, optical touch sensors, optical proximity sensors, and/or other touch sensors and/or proximity sensors, monochromatic and color ambient light sensors, three-dimensional sensors (e.g., three-dimensional image sensors such as structured light sensors that emit beams of light and that use two-dimensional digital image sensors to gather image data for three-dimensional images from light spots that are produced when a target is illuminated by the beams of light, binocular three-dimensional image sensors that gather three-dimensional images using two or more cameras in a binocular imaging arrangement, three-dimensional lidar (light detection and ranging) sensors, three-dimensional radio-frequency sensors, or other sensors that gather three-dimensional image data), cameras (e.g., infrared and/or visible digital image sensors), fingerprint sensors, temperature sensors, sensors for measuring three-dimensional non-contact gestures (“air gestures”), pressure sensors, sensors for detecting position, orientation, and/or motion (e.g., accelerometers, magnetic sensors such as compass sensors, gyroscopes, and/or inertial measurement units that contain some or all of these sensors), health sensors, radio-frequency sensors, depth sensors (e.g., structured light sensors and/or depth sensors based on stereo imaging devices), humidity sensors, moisture sensors, gaze tracking sensors, and/or other sensors. 
     Control circuitry  16  may be used to run software on device  10  such as operating system code and applications. During operation of device  10 , the software running on control circuitry  16  may display images on display  14  using an array of pixels in display  14 . 
     Display  14  may be an organic light-emitting diode display, a liquid crystal display, an electrophoretic display, an electrowetting display, a plasma display, a microelectromechanical systems display, a display having a pixel array formed from crystalline semiconductor light-emitting diode dies (sometimes referred to as microLEDs), and/or other display. Configurations in which display  14  is an organic light-emitting diode display are sometimes described herein as an example. 
     Display  14  may have a rectangular shape (i.e., display  14  may have a rectangular footprint and a rectangular peripheral edge that runs around the rectangular footprint) or may have other suitable shapes. Display  14  may have one or more rounded corners. Display  14  may be planar or may have a curved profile. 
     Device  10  may include cameras and other components that form part of gaze and/or head tracking system  18 . The camera(s) or other components of system  18  may face an expected location for a viewer and may track the viewer&#39;s eyes and/or head (e.g., images and other information captured by system  18  may be analyzed by control circuitry  16  to determine the location of the viewer&#39;s eyes and/or head). This head-location information obtained by system  18  may be used to determine the appropriate direction with which display content from display  14  should be directed. Eye and/or head tracking system  18  may include any desired number/combination of infrared and/or visible light detectors. Eye and/or head tracking system  18  may optionally include light emitters to illuminate the scene. 
     A top view of a portion of display  14  is shown in  FIG.  2   . As shown in  FIG.  2   , display  14  may have an array  62  of pixels  22  formed on substrate  36 . Substrate  36  may be formed from glass, metal, plastic, ceramic, or other substrate materials. Pixels  22  may receive data signals over signal paths such as data lines D and may receive one or more control signals over control signal paths such as horizontal control lines G (sometimes referred to as gate lines, scan lines, emission control lines, etc.). There may be any suitable number of rows and columns of pixels  22  in display  14  (e.g., tens or more, hundreds or more, or thousands or more). Each pixel  22  may have a light-emitting diode  26  that emits light  24  under the control of a pixel circuit formed from thin-film transistor circuitry (such as thin-film transistors  28  and thin-film capacitors). Thin-film transistors  28  may be polysilicon thin-film transistors, semiconducting-oxide thin-film transistors such as indium gallium zinc oxide transistors, or thin-film transistors formed from other semiconductors. Pixels  22  may contain light-emitting diodes of different colors (e.g., red, green, and blue diodes for red, green, and blue pixels, respectively) to provide display  14  with the ability to display color images. 
     Display driver circuitry may be used to control the operation of pixels  22 . The display driver circuitry may be formed from integrated circuits, thin-film transistor circuits, or other suitable circuitry. Display driver circuitry  30  of  FIG.  2    may contain communications circuitry for communicating with system control circuitry such as control circuitry  16  of  FIG.  1    over path  32 . Path  32  may be formed from traces on a flexible printed circuit or other cable. During operation, the control circuitry (e.g., control circuitry  16  of  FIG.  1   ) may supply circuitry  30  with information on images to be displayed on display  14 . 
     To display the images on display pixels  22 , display driver circuitry  30  may supply image data to data lines D while issuing clock signals and other control signals to supporting display driver circuitry such as gate driver circuitry  34  over path  38 . If desired, circuitry  30  may also supply clock signals and other control signals to gate driver circuitry on an opposing edge of display  14 . 
     Gate driver circuitry  34  (sometimes referred to as horizontal control line control circuitry) may be implemented as part of an integrated circuit and/or may be implemented using thin-film transistor circuitry. Horizontal control lines G in display  14  may carry gate line signals (scan line signals), emission enable control signals, and other horizontal control signals for controlling the pixels of each row. There may be any suitable number of horizontal control signals per row of pixels  22  (e.g., one or more, two or more, three or more, four or more, etc.). 
     Display  14  may sometimes be a stereoscopic display that is configured to display three-dimensional content for a viewer. Stereoscopic displays are capable of displaying multiple two-dimensional images that are viewed from slightly different angles. When viewed together, the combination of the two-dimensional images creates the illusion of a three-dimensional image for the viewer. For example, a viewer&#39;s left eye may receive a first two-dimensional image and a viewer&#39;s right eye may receive a second, different two-dimensional image. The viewer perceives these two different two-dimensional images as a single three-dimensional image. 
     There are numerous ways to implement a stereoscopic display. Display  14  may be a lenticular display that uses lenticular lenses (e.g., elongated lenses that extend along parallel axes), may be a parallax barrier display that uses parallax barriers (e.g., an opaque layer with precisely spaced slits to create a sense of depth through parallax), may be a volumetric display, or may be any other desired type of stereoscopic display. Configurations in which display  14  is a lenticular display are sometimes described herein as an example. 
       FIG.  3    is a cross-sectional side view of an illustrative lenticular display that may be incorporated into electronic device  10 . Display  14  includes a display panel  20  with pixels  22  on substrate  36 . Substrate  36  may be formed from glass, metal, plastic, ceramic, or other substrate materials and pixels  22  may be organic light-emitting diode pixels, liquid crystal display pixels, or any other desired type of pixels. 
     As shown in  FIG.  3   , lenticular lens film  42  may be formed over the display pixels. Lenticular lens film  42  (sometimes referred to as a light redirecting film, a lens film, etc.) includes lenses  46  and a base film portion  44  (e.g., a planar film portion to which lenses  46  are attached). Lenses  46  may be lenticular lenses that extend along respective longitudinal axes (e.g., axes that extend into the page parallel to the Y-axis). Lenses  46  may be referred to as lenticular elements  46 , lenticular lenses  46 , optical elements  46 , etc. 
     The lenses  46  of the lenticular lens film cover the pixels of display  14 . An example is shown in  FIG.  3    with display pixels  22 - 1 ,  22 - 2 ,  22 - 3 ,  22 - 4 ,  22 - 5 , and  22 - 6 . In this example, display pixels  22 - 1  and  22 - 2  are covered by a first lenticular lens  46 , display pixels  22 - 3  and  22 - 4  are covered by a second lenticular lens  46 , and display pixels  22 - 5  and  22 - 6  are covered by a third lenticular lens  46 . The lenticular lenses may redirect light from the display pixels to enable stereoscopic viewing of the display. 
     Consider the example of display  14  being viewed by a viewer with a first eye (e.g., a right eye)  48 - 1  and a second eye (e.g., a left eye)  48 - 2 . Light from pixel  22 - 1  is directed by the lenticular lens film in direction  40 - 1  towards left eye  48 - 2 , light from pixel  22 - 2  is directed by the lenticular lens film in direction  40 - 2  towards right eye  48 - 1 , light from pixel  22 - 3  is directed by the lenticular lens film in direction  40 - 3  towards left eye  48 - 2 , light from pixel  22 - 4  is directed by the lenticular lens film in direction  40 - 4  towards right eye  48 - 1 , light from pixel  22 - 5  is directed by the lenticular lens film in direction  40 - 5  towards left eye  48 - 2 , light from pixel  22 - 6  is directed by the lenticular lens film in direction  40 - 6  towards right eye  48 - 1 . In this way, the viewer&#39;s right eye  48 - 1  receives images from pixels  22 - 2 ,  22 - 4 , and  22 - 6 , whereas left eye  48 - 2  receives images from pixels  22 - 1 ,  22 - 3 , and  22 - 5 . Pixels  22 - 2 ,  22 - 4 , and  22 - 6  may be used to display a slightly different image than pixels  22 - 1 ,  22 - 3 , and  22 - 5 . Consequently, the viewer may perceive the received images as a single three-dimensional image. 
     Pixels of the same color may be covered by a respective lenticular lens  46 . In one example, pixels  22 - 1  and  22 - 2  may be red pixels that emit red light, pixels  22 - 3  and  22 - 4  may be green pixels that emit green light, and pixels  22 - 5  and  22 - 6  may be blue pixels that emit blue light. This example is merely illustrative. In general, each lenticular lens may cover any desired number of pixels each having any desired color. The lenticular lens may cover a plurality of pixels having the same color, may cover a plurality of pixels each having different colors, may cover a plurality of pixels with some pixels being the same color and some pixels being different colors, etc. 
       FIG.  4    is a cross-sectional side view of an illustrative stereoscopic display showing how the stereoscopic display may be viewable by multiple viewers. The stereoscopic display of  FIG.  3    may have one optimal viewing position (e.g., one viewing position where the images from the display are perceived as three-dimensional). The stereoscopic display of  FIG.  4    may have two or more optimal viewing positions (e.g., two or more viewing positions where the images from the display are perceived as three-dimensional). 
     Display  14  may be viewed by both a first viewer with a right eye  48 - 1  and a left eye  48 - 2  and a second viewer with a right eye  48 - 3  and a left eye  48 - 4 . Light from pixel  22 - 1  is directed by the lenticular lens film in direction  40 - 1  towards left eye  48 - 4 , light from pixel  22 - 2  is directed by the lenticular lens film in direction  40 - 2  towards right eye  48 - 3 , light from pixel  22 - 3  is directed by the lenticular lens film in direction  40 - 3  towards left eye  48 - 2 , light from pixel  22 - 4  is directed by the lenticular lens film in direction  40 - 4  towards right eye  48 - 1 , light from pixel  22 - 5  is directed by the lenticular lens film in direction  40 - 5  towards left eye  48 - 4 , light from pixel  22 - 6  is directed by the lenticular lens film in direction  40 - 6  towards right eye  48 - 3 , light from pixel  22 - 7  is directed by the lenticular lens film in direction  40 - 7  towards left eye  48 - 2 , light from pixel  22 - 8  is directed by the lenticular lens film in direction  40 - 8  towards right eye  48 - 1 , light from pixel  22 - 9  is directed by the lenticular lens film in direction  40 - 9  towards left eye  48 - 4 , light from pixel  22 - 10  is directed by the lenticular lens film in direction  40 - 10  towards right eye  48 - 3 , light from pixel  22 - 11  is directed by the lenticular lens film in direction  40 - 11  towards left eye  48 - 2 , and light from pixel  22 - 12  is directed by the lenticular lens film in direction  40 - 12  towards right eye  48 - 1 . In this way, the first viewer&#39;s right eye  48 - 1  receives images from pixels  22 - 4 ,  22 - 8 , and  22 - 12 , whereas left eye  48 - 2  receives images from pixels  22 - 3 ,  22 - 7 , and  22 - 11 . Pixels  22 - 4 ,  22 - 8 , and  22 - 12  may be used to display a slightly different image than pixels  22 - 3 ,  22 - 7 , and  22 - 11 . Consequently, the first viewer may perceive the received images as a single three-dimensional image. Similarly, the second viewer&#39;s right eye  48 - 3  receives images from pixels  22 - 2 ,  22 - 6 , and  22 - 10 , whereas left eye  48 - 4  receives images from pixels  22 - 1 ,  22 - 5 , and  22 - 9 . Pixels  22 - 2 ,  22 - 6 , and  22 - 10  may be used to display a slightly different image than pixels  22 - 1 ,  22 - 5 , and  22 - 9 . Consequently, the second viewer may perceive the received images as a single three-dimensional image. 
     Pixels of the same color may be covered by a respective lenticular lens  46 . In one example, pixels  22 - 1 ,  22 - 2 ,  22 - 3 , and  22 - 4  may be red pixels that emit red light, pixels  22 - 5 ,  22 - 6 ,  22 - 7 , and  22 - 8  may be green pixels that emit green light, and pixels  22 - 9 ,  22 - 10 ,  22 - 11 , and  22 - 12  may be blue pixels that emit blue light. This example is merely illustrative. The display may be used to present the same three-dimensional image to both viewers or may present different three-dimensional images to different viewers. In some cases, control circuitry in the electronic device  10  may use eye and/or head tracking system  18  to track the position of one or more viewers and display images on the display based on the detected position of the one or more viewers. 
     It should be understood that the lenticular lens shapes and directional arrows of  FIGS.  3  and  4    are merely illustrative. The actual rays of light from each pixel may follow more complicated paths (e.g., with redirection occurring due to refraction, total internal reflection, etc.). Additionally, light from each pixel may be emitted over a range of angles. The lenticular display may also have lenticular lenses of any desired shape or shapes. Each lenticular lens may have a width that covers two pixels, three pixels, four pixels, more than four pixels, more than ten pixels, more than fifteen pixels, less than twenty-five pixels, etc. Each lenticular lens may have a length that extends across the entire display (e.g., parallel to columns of pixels in the display). 
       FIG.  5    is a top view of an illustrative lenticular lens film that may be incorporated into a lenticular display. As shown in  FIG.  5   , elongated lenses  46  extend across the display parallel to the Y-axis. For example, the cross-sectional side view of  FIGS.  3  and  4    may be taken looking in direction  50 . The lenticular display may include any desired number of lenticular lenses  46  (e.g., more than 10, more than 100, more than 1,000, more than 10,000, etc.). In  FIG.  5   , the lenticular lenses extend perpendicular to the upper and lower edge of the display panel. This arrangement is merely illustrative, and the lenticular lenses may instead extend at a non-zero, non-perpendicular angle (e.g., diagonally) relative to the display panel if desired. 
       FIG.  6    is a schematic diagram of an illustrative electronic device showing how information from eye and/or head tracking system  18  may be used to control operation of the display. As shown in  FIG.  6   , display  14  is capable of providing unique images across a number of distinct zones. In  FIG.  6   , display  14  emits light across  14  zones, each having a respective angle of view  52 . The angle  52  may be between 1° and 2°, between 0° and 4°, less than 5°, less than 3°, less than 2°, less than 1.5°, greater than 0.5°, or any other desired angle. Each zone may have the same associated viewing angle or different zones may have different associated viewing angles. 
     The example herein of the display having 14 independently controllable zones is merely illustrative. In general, the display may have any desired number of independently controllable zones (e.g., more than 2, more than 6, more than 10, more than 12, more than 16, more than 20, more than 30, more than 40, less than 40, between 10 and 30, between 12 and 25, etc.). 
     Each zone is capable of displaying a unique image to the viewer. The sub-pixels on display  14  may be divided into groups, with each group of sub-pixels capable of displaying an image for a particular zone. For example, a first subset of sub-pixels in display  14  is used to display an image (e.g., a two-dimensional image) for zone  1 , a second subset of sub-pixels in display  14  is used to display an image for zone  2 , a third subset of sub-pixels in display  14  is used to display an image for zone  3 , etc. In other words, the sub-pixels in display  14  may be divided into 14 groups, with each group associated with a corresponding zone (sometimes referred to as viewing zone) and capable of displaying a unique image for that zone. The sub-pixel groups may also themselves be referred to as zones. 
     Control circuitry  16  may control display  14  to display desired images in each viewing zone. There is much flexibility in how the display provides images to the different viewing zones. Display  14  may display entirely different content in different zones of the display. For example, an image of a first object (e.g., a cube) is displayed for zone  1 , an image of a second, different object (e.g., a pyramid) is displayed for zone  2 , an image of a third, different object (e.g., a cylinder) is displayed for zone  3 , etc. This type of scheme may be used to allow different viewers to view entirely different scenes from the same display. However, in practice there may be crosstalk between the viewing zones. As an example, content intended for zone  3  may not be contained entirely within viewing zone  3  and may leak into viewing zones  2  and  4 . 
     Therefore, in another possible use-case, display  14  may display a similar image for each viewing zone, with slight adjustments for perspective between each zone. This may be referred to as displaying the same content at different perspectives (or different views), with one image corresponding to a unique perspective of the same content. For example, consider an example where the display is used to display a three-dimensional cube. The same content (e.g., the cube) may be displayed on all of the different zones in the display. However, the image of the cube provided to each viewing zone may account for the viewing angle associated with that particular zone. In zone  1 , for example, the viewing cone may be at a −10° angle relative to the surface normal of the display. Therefore, the image of the cube displayed for zone  1  may be from the perspective of a −10° angle relative to the surface normal of the cube (as in  FIG.  7 A ). Zone  7 , in contrast, is at approximately the surface normal of the display. Therefore, the image of the cube displayed for zone  7  may be from the perspective of a 0° angle relative to the surface normal of the cube (as in  FIG.  7 B ). Zone  14  is at a 10° angle relative to the surface normal of the display. Therefore, the image of the cube displayed for zone  14  may be from the perspective of a 10° angle relative to the surface normal of the cube (as in  FIG.  7 C ). As a viewer progresses from zone  1  to zone  14  in order, the appearance of the cube gradually changes to simulate looking at a real-world object. 
     There are many possible variations for how display  14  displays content for the viewing zones. In general, each viewing zone may be provided with any desired image based on the application of the electronic device. Different zones may provide different images of the same content at different perspectives, different zones may provide different images of different content, etc. 
       FIG.  8    is a schematic diagram of an electronic device including display pipeline circuitry. The display pipeline circuitry  64  provides pixel data to display driver circuitry  30  for display on pixel array  62 . Pipeline circuitry  64  may use various inputs to render an image and generate pixel brightness values for each pixel in the pixel array based on the image. In the example of  FIG.  8   , the display may be used to provide images of the same content at different perspectives in each viewing zone. In other words, each subset of the pixel array associated with a given viewing zone displays a different view of the same content. As a viewer changes viewing zones, the appearance of the content gradually changes to simulate looking at a real-world object. 
     There are numerous steps that may be involved in display pipeline circuitry  64  generating pixel data for the pixel array. First, the display pipeline circuitry may render content that is intended to be displayed by the lenticular display. The display pipeline circuitry may render a plurality of two-dimensional images of target content, with each two-dimensional image corresponding to a different view of the target content. In one example, the target content may be based on a two-dimensional (2D) image and a three-dimensional (3D) image. The two-dimensional image and the three-dimensional image may optionally be captured by a respective two-dimensional image sensor and three-dimensional image sensor in electronic device  10 . This example is merely illustrative. The content may be rendered based on two-dimensional/three-dimensional images from other sources (e.g., from sensors on another device, computer-generated images, etc.). 
     The two-dimensional images associated with different views may be compensated based on various factors (e.g., a brightness setting for the device, ambient light levels, etc.). After the two-dimensional images of different views are compensated, the plurality of two-dimensional images may be combined and provided to the single pixel array  62 . A display calibration map may be used to determine which pixels in the pixel array correspond to each view (e.g., each of the plurality of two-dimensional images). Additional compensation steps may be performed after determining the pixel data for the entire pixel array based on the plurality of different views. Once the additional compensation is complete, the pixel data may be provided to the display driver circuitry  30 . The pixel data provided to display driver circuitry  30  includes a brightness level (e.g., voltage) for each pixel in pixel array  62 . These brightness levels are used to simultaneously display a plurality of two-dimensional images on the pixel array, each two-dimensional image corresponding to a unique view of the target content that is displayed in a respective unique viewing zone. 
       FIG.  9    is a schematic diagram showing additional details of the display pipeline circuitry of  FIG.  8   . As shown in  FIG.  9   , display pipeline circuitry  64  may include content rendering circuitry  102 , pre-processing circuitry  104 , tone mapping circuitry  106 , ambient light adaptation circuitry  108 , white point calibration circuitry  110 , dithering circuitry  112 , pixel mapping circuitry  114 , color compensation circuitry  116 , border masking circuitry  118 , burn-in compensation circuitry  120 , and panel response correction circuitry  122 . 
     Content rendering circuitry  102  may render a two-dimensional image for each respective viewing zone in the display. In the example of  FIG.  6   , the display has 14 viewing zones. In this example, content rendering circuitry  102  would render 14 two-dimensional images, with one two-dimensional image for each viewing zone. As previously discussed, there is flexibility in the type of content that is displayed in each of the viewing zones. However, herein an illustrative example will be described where the viewing zones are used to display images of the same content at different perspectives (views). In other words, each subset of the pixel array associated with a given viewing zone displays a different view of the same content. As a viewer changes viewing zones, the appearance of the content gradually changes to simulate looking at a real-world object. Each one of the plurality of views (e.g., two-dimensional images) rendered by circuitry  102  may include a respective target brightness value for each pixel in a target two-dimensional image. 
     Content rendering circuitry  102  may render content for the plurality of views based on a two-dimensional image and a three-dimensional image. The two-dimensional image and three-dimensional image may be images of the same content. In other words, the two-dimensional image may provide color/brightness information for given content while the three-dimensional image provides a depth map associated with the given content. The two-dimensional image only has color/brightness information for one view of the given content. However, content rendering circuitry  102  may render two-dimensional images for additional views based on the depth map and the two-dimensional image from the original view. Content rendering circuitry  102  may render as many two-dimensional images (views) as there are viewing zones in the display (e.g., more than 1, more than 2, more than 6, more than 10, more than 12, more than 16, more than 20, more than 30, more than 40, less than 40, between 10 and 30, between 12 and 25, etc.). 
     Content rendering circuitry  102  may optionally include a machine learning model. The machine learning model may use additional information (e.g., additional images of the content) to render two-dimensional images (views) for each viewing zone in the display. 
     After content rendering circuitry  102  generates content for a plurality of different views, each view may undergo processing from per-view processing circuitry  124 . Per-view processing circuitry  124  (sometimes referred to as per-2D-image compensation circuitry  124 , pre-mapping processing circuitry  124 , etc.) may individually process each two-dimensional image rendered by circuitry  102 . The per-view processing circuitry is used to make content adjustments that are based on the perceived image that ultimately reaches the viewer (e.g., the pixels that are adjacent on the user&#39;s retina when viewing the display). As shown in  FIG.  9   , per-view processing circuitry  124  includes tone mapping circuitry  106 , ambient light adaptation circuitry  108 , white point calibration circuitry  110 , and dithering circuitry  112 . 
     Pre-processing circuitry  104  may be used to adjust each two-dimensional image to improve sharpness and mitigate aliasing. Once the two-dimensional image is ultimately displayed on pixel array  62  for viewing in a given viewing zone, the lenticular lenses in the display anisotropically magnify the image in the given viewing zone. In the example of  FIG.  5   , the lenticular lenses magnify light in the X-dimension while not magnifying the light in the Y-dimension. This anisotropic magnification may cause aliasing in the image perceived by the user. 
     To mitigate the aliasing and improve image quality, the two-dimensional image is pre-processed by circuitry  104 . Pre-processing circuitry  104  may apply an anisotropic low-pass filter to the two-dimensional image. This mitigates aliasing when the pre-processed image is displayed and perceived by a viewer. As another option, the content may be resized by pre-processing circuitry  104 . In other words, pre-processing circuitry  104  may change the aspect ratio of the two-dimensional image for a given view (e.g., by shrinking the image in the X-direction that is effected by the lenticular lenses). Anisotropic resizing of this type mitigates aliasing when the pre-processed image is displayed and perceived by the viewer. 
     The example of pre-processing circuitry processing image data from content rendering circuitry  102  is merely illustrative. In another example, the pre-processing may occur during the initial rendering (e.g., content rendering circuitry  102  performs the pre-processing). 
     After pre-processing circuitry  104  pre-processes each image, tone mapping circuitry  106  may be used to select a content-luminance-to-display luminance mapping to be used in displaying content on the display. A content-luminance-to-display-luminance mapping may be characterized by tone mapping parameters such as a black level, a reference white level, a specular white level, skin tone level, and the slope or the gamma of the mapping. As shown in  FIG.  9   , the tone mapping parameters may be selected based on factors such as ambient light level and brightness setting. These examples are merely illustrative, and other factors may be used to select the tone mapping parameters if desired (e.g., content statistics, display characteristics, point of gaze information, power source and consumption information, per-window information, etc.). 
     With one illustrative configuration, tone mapping circuitry  106  may select a desired tone mapping curve based on operating conditions such as display brightness settings (e.g., user defined brightness settings and brightness levels set by device  10  to accommodate a normal power operating mode and a low-power operating mode), ambient conditions (ambient light level and ambient light color), content statistics (e.g., information on average pixel luminance and burn-in risk or other information on operating conditions having a potential impact on display lifetime, quality information, dynamic range information etc.), display characteristics (e.g., display limitations such as maximum achievable pixel luminance), power constraints (e.g., due to thermal limitations and/or other considerations), whether device  10  is operating on DC power (power from a battery) or AC power, etc. 
     After tone mapping is performed by tone mapping circuitry  106 , each view may have an associated two-dimensional array of display luminance values (that are obtained using the identified tone maps). 
     Next, ambient light level adaptation circuitry  108  may be used to adjust the two-dimensional images based on the ambient light level and/or ambient light color. The ambient light information used by circuitry  108  may be obtained by an ambient light sensor in device  10 . Ambient light level adaptation circuitry  108  may also use information such as a brightness setting (e.g., a user defined brightness setting, a brightness setting associated with an operating mode such as a normal operating mode or low-power operating mode) to compensate each view. Ambient light level adaptation circuitry  108  may be used to adjust the brightness and color of each two-dimensional image based on the ambient light level and ambient light color. Adapting the content to the ambient viewing conditions in this way may improve the image quality for the user. White point calibration circuitry  110  may be used to adjust the white point of the display (e.g., based on the ambient light level, brightness settings, and/or other operating conditions) during white point calibration operations. 
     After the content from circuitry  102  is processed by pre-processing circuitry  104 , tone mapping circuitry  106 , ambient light adaptation circuitry  108 , and white point calibration circuitry  110 , dithering circuitry  112  may be used to dither the display luminance values. Dithering the luminance values may involve blending the luminance values of different pixels on the panel by randomly adding noise to the luminance values. Adding noise to the luminance values in this manner may reduce distortion when the image is ultimately displayed by the pixel array, manipulated by the lenticular lenses, and viewed by the viewer. 
     After each two-dimensional image is independently processed by circuitry  124 , the two-dimensional images may be mapped to pixels in the pixel array using pixel mapping circuitry  114 . Pixel mapping circuitry  114  may receive all of the two-dimensional images that are independently processed by per-view processing circuitry  124 . Pixel mapping circuitry  114  may also receive (or include) a display calibration map that indicates how each view corresponds to the pixel array. 
     For example, the pixel mapping circuitry may receive a first two-dimensional image that corresponds to a first view intended for viewing zone  1  of the display. The display calibration map may identify a first subset of pixels in the pixel array that is visible at viewing zone  1 . Accordingly, the first two-dimensional image is mapped to the first subset of pixels. Once displayed, the first two-dimensional image is viewable at viewing zone  1 . The pixel mapping circuitry may also receive a second two-dimensional image that corresponds to a second view intended for viewing zone  2  of the display. The display calibration map may identify a second subset of pixels in the pixel array that is visible at viewing zone  2 . Accordingly, the second two-dimensional image is mapped to the second subset of pixels. Once displayed, the second two-dimensional image is viewable at viewing zone  2 . This type of pixel mapping is repeated for every view included in the display. Once complete, pixel mapping circuitry  114  outputs pixel data for each pixel in the pixel array. The pixel data includes a blend of all of the independent, two-dimensional images from per-view processing circuitry  124 . 
     It should be understood that the subset of pixels used to display each view may be non-continuous. For example, the subset of pixels for each view may include a plurality of discrete vertical pixel strips. These discrete sections of pixels may be separated by pixels that are used to display other views to the viewer. 
     In some cases, the array of pixels may be at an angle relative to the lenticular lenses. For example, the array of pixels may extend diagonally and the lenticular lenses may extend vertically. The display calibration map may take into account the diagonal arrangement of the pixels. 
     After pixel mapping is complete, panel-level processing circuitry  126  (sometimes referred to as post-mapping processing circuitry  126 ) may be used to perform additional processing on the pixel data. Panel-level processing circuitry  126  may include color compensation circuitry  116 , border masking circuitry  118 , burn-in compensation circuitry  120 , and panel response correction circuitry  122 . In contrast to per-view processing circuitry  124 , panel-level processing circuitry  126  may be used to make adjustments that are based on the pixels on the display panel (as opposed to perceived pixels at the user&#39;s eye). 
     Color compensation circuitry  116  may be used to compensate the pixel data using a color look up table. Color compensation circuitry  116  may adjust the color of the pixel data. 
     Border masking circuitry  118  may be used to impart a desired shape to the light-emitting area of the display. For example, the display may include a rectangular array of pixels. If all of the pixels in the rectangular array emitted light, the display area would appear to be rectangular. In some cases, however, it may be desirable for the light-emitting area of the display to have a different shape (e.g., rounded corners). Portions of the display may therefore be dimmed (masked) to impart a desired shape to the visible area of the display. As one example, the display may be masked such that the light-emitting area has a rectangular shape with rounded corners. 
     In one possible scheme, pixels outside of the target area may be turned entirely off to achieve the desired shape. However, in some cases, a binary on/off scheme results in jagged edges to the target shape. For example, the target curved corner may have a jagged appearance instead of appearing as a smooth curve. To mitigate this type of undesired jaggedness, the pixels in the area adjacent to the border between the active (light-emitting) and inactive (non-light-emitting) areas of the display may be partially dimmed. For example, each pixel in this region may have an associated dimming factor. Border masking circuitry  118  may apply the dimming factor for each pixel to that pixel to modify the pixel data. Pixels far outside the active area may be totally dimmed (e.g., turned off). Pixels closer to the active area may be partially dimmed (e.g., the pixels are dimmed but still emit light) such that a smooth curve is achieved at the border. The border masking circuitry  118  may be used to apply any desired shape to the active area of the display. 
     Burn-in compensation circuitry  120  may be used to compensate the pixel data to mitigate risk of burn-in and/or mitigate visible artifacts caused by burn-in. Some displays such as plasma displays and organic light-emitting diode displays may be subject to burn-in effects. Burn-in may result when a static image is displayed on a display for an extended period of time. This can cause uneven wear on the pixels of the display. If care is not taken, burn-in effects can lead to the creation of undesired ghost images on a display. 
     To help avoid burn-in effects, burn-in compensation circuitry  120  may impose burn-in constraints on the pixel data. The constraints that are imposed may include peak luminance constraints, dwell time constraints, color constraints, constraints on the shapes and sizes of displayed elements, and constraints on element style. These constraints may help equalize pixel wear across the display and thereby avoid situations in which static elements create burn-in. Pixel usage history may be taken into account when performing burn-in mitigation operations. For example, burn-in compensation circuitry  120  may determine how long a given pixel in the array has been static, the long-term total usage of that pixel, etc. Based on this information, burn-in compensation circuitry may adjust the pixel brightness (e.g., to mitigate additional burn-in). Burn-in compensation circuitry may also use the pixel usage history to prevent burn-in from causing visible artifacts in the display (e.g., by increasing or decreasing the brightness of the pixels based on usage history). 
     Panel response correction circuitry  122  (sometimes referred to as gamma correction circuitry  122 ) may be used to map luminance levels for each pixel to voltage levels (e.g., voltages applied to the pixels using display driver circuitry). A gamma curve (e.g., brightness vs. voltage) may be used to identify appropriate pixel voltages for each target pixel luminance level. The target pixel voltages are then provided to display driver circuitry  30 . Display driver circuitry  30  provides the target pixel voltages to pixel array  62  using data lines (e.g., D in  FIG.  2   ). The images are then displayed on display  14 . 
     It should be noted that display pipeline circuitry  64  (content rendering circuitry  102 , pre-processing circuitry  104 , tone mapping circuitry  106 , ambient light adaptation circuitry  108 , white point calibration circuitry  110 , dithering circuitry  112 , pixel mapping circuitry  114 , color compensation circuitry  116 , border masking circuitry  118 , burn-in compensation circuitry  120 , and panel response correction circuitry  122 ) may be implemented using one or more microprocessors, microcontrollers, digital signal processors, graphics processing units, application-specific integrated circuits, and other integrated circuits. In one example, rendering circuitry  102 , pre-processing circuitry  104 , tone mapping circuitry  106 , ambient light adaptation circuitry  108 , white point calibration circuitry  110 , dithering circuitry  112 , and pixel mapping circuitry  114  may be formed in a graphics processing unit and color compensation circuitry  116 , border masking circuitry  118 , burn-in compensation circuitry  120 , and panel response correction circuitry  122  may be formed in a separate application-specific integrated circuit. 
     The illustrative order of operations described in connection with  FIG.  9    is merely illustrative. In general, the circuitry of  FIG.  9    may process pixel data for the display in any desired order. However, there may be some advantageous to the order presented in  FIG.  9   . 
     For example, it should be noted that per-view processing circuitry  124  is used to process the pixel data before pixel mapping whereas panel-level processing circuitry  126  is used to process the pixel data after pixel mapping. This allows processing that relies on the final view of the image (e.g., per-view processing) to be completed before the data is split to a subset of pixels on the panel and interleaved with other views during pixel mapping. Once pixel mapping is complete, the processing that relies on the full panel luminance values (e.g., panel-level processing) may be completed. 
     As another example, it may be advantageous for tone mapping circuitry  106  to perform tone mapping before the white point calibration is performed by white point calibration circuitry  110 . Additionally, it may be advantageous for panel response correction circuitry  122  to process the pixel data last (so that the pixel data remains in the luminance instead of voltage domain during processing). 
       FIG.  10    is a flowchart of illustrative method steps for operating an electronic device with a pipeline of the type shown in  FIG.  9   . As shown in  FIG.  10   , control circuitry (e.g., content rendering circuitry  102 ) may render content for multiple views at step  202 . The content rendered at step  202  may be based on a two-dimensional image and a three-dimensional image, in one example. Each one of the multiple views may be a two-dimensional image of the same content from a different perspective, in one example. The multiple views may instead include different two-dimensional images of entirely different content in another example (e.g., to display one type of content to one user and a different type of content to another user). 
     At step  204 , the rendered content for each view is pre-processed by the control circuitry (e.g., pre-processing circuitry  104 ). The pre-processing may include filtering and/or reshaping the content to mitigate aliasing when the images are later displayed. 
     At step  206 , control circuitry (e.g., tone mapping circuitry  106 ) is used to perform tone mapping on the rendered content for each view. The tone mapping may involve converting content luminance values to display luminance values based on tone maps. The tone maps may be adjusted based on various factors such as the brightness setting (e.g., a brightness setting provided by the user using an input component) and/or the ambient light level (e.g., obtained by an ambient light sensor in the device). 
     At step  208 , control circuitry (e.g., ambient light adaptation circuitry  108 ) may adjust the rendered content for each view based on ambient light (and/or the brightness setting). The display luminance values for each pixel in the rendered content may optionally be adjusted. The ambient light levels used at step  208  may be obtained by an ambient light sensor in the device. 
     At step  210 , control circuitry (e.g., white point calibration circuitry  110 ) may adjust the rendered content for each view based on white point. The white point calibration circuitry may adjust the white point for the display based on the brightness setting (e.g., a brightness setting provided by the user using an input component) and/or the ambient light level (e.g., obtained by an ambient light sensor in the device). 
     At step  212 , control circuitry (e.g., dithering circuitry  112 ) may be used to dither the rendered content for each view. Dithering the content may include adding white noise to the display luminance values to blend the display luminance values. In general, any desired type of dithering may be performed. The dithering may improve image quality in the displayed images. 
     At step  214 , control circuitry (e.g., pixel mapping circuitry  114 ) may be used to map the rendered content (e.g., the processed content) for each view into the pixel array of a single display panel (e.g., display panel  20  with pixel array  62 ). The pixel mapping circuitry  114  may use a display calibration map to assign the display luminance values of each view to a respective subset of pixels on the display panel. 
     At step  216 , control circuitry (e.g., color compensation circuitry  116 ) may perform color compensation (e.g., using a color look up table). 
     At step  218 , control circuitry (e.g., border masking circuitry  118 ) may apply border masking such that the active area (light-emitting area) of the display has a desired shape. Pre-determined dimming factors may be applied to the display luminance values by border masking circuitry  118  (e.g., such that the active area has a smooth border). 
     At step  220 , control circuitry (e.g., burn-in compensation circuitry  120 ) may perform burn-in compensation. The burn-in compensation may be used to mitigate burn-in and/or mitigate visible artifacts on the display as a result of burn-in. 
     At step  222 , control circuitry (e.g., panel response correction circuitry  122 ) may apply a panel response correction. The panel response correction may be used to map the target display luminance values for the pixels to corresponding voltages. Gamma curves may be used to convert the display luminance values to voltages. 
     At step  224 , display driver circuitry may provide data to the pixel array (e.g. using data lines). The data may include the voltages output from panel response correction circuitry  122 . The pixel array emits light for each of the views based on the received data (voltages) from the display driver circuitry. 
     Steps  204  through  212  may be referred to as per-view processing steps and may be performed before pixel mapping. Steps  216  through  222  may be referred to as panel-level processing steps and may be performed after pixel mapping. 
       FIGS.  9  and  10    show an arrangement where multiple two-dimensional images are rendered for respective viewing zones in the display. Subsequently, a display calibration map is used to determine which pixels in the pixel array correspond to each view (e.g., each of the plurality of two-dimensional images). In this example, the display calibration map may identify a first subset of pixels in the pixel array that is visible at a first viewing zone, a second subset of pixels in the pixel array that is visible at a second viewing zone, etc. This example is merely illustrative. 
     In an alternate arrangement, shown in  FIG.  11   , ray tracing circuitry  128  may be included in display pipeline circuitry  64 . In  FIG.  11   , a two-dimensional image of given content (e.g., content intended for display on display  14 ) may be provided to pre-processing circuitry  104 . The two-dimensional image of the given content may undergo the subsequent processing by circuitry  104 ,  106 ,  108 , and  110 . Calibration circuitry  110  in  FIG.  11    is primary display calibration circuitry (e.g., that calibrates the display using brightness setting and/or ambient light level). 
     Ray tracing circuitry  128  may use the two-dimensional image of the given content, a three-dimensional image of the given content, and stored deflection measurements  130  to determine a display calibration map that is used by pixel mapping circuitry  114 . The two-dimensional image and the three-dimensional image may be images captured by one or more sensors in input-output devices  12  of electronic device  10 . Alternatively, the two-dimensional image and/or the three-dimensional image may be computer-generated images or images captured by one or more sensors in another electronic device. In the event that the two-dimensional image and/or the three-dimensional image are computer-generated images, the computer-generated images may optionally be based on images captured by one or more sensors in input-output devices  12  of electronic device  10  or may optionally be based on images captured by one or more sensors in another electronic device. 
     The stored deflection measurements  130  may be stored in any desired type of memory. The stored deflection measurements may include, for each sub-pixel in display  14 , a horizontal deflection angle of light emitted by that sub-pixel. 
       FIG.  12    is a side view of display  14  showing how the ray tracing process may be performed by ray tracing circuitry  128 . As shown, a given sub-pixel  22 - 1  within display  14  may emit light in direction  132  (e.g., after the light is deflected by the lenticular lenses  42  as previously shown). Direction  132  may be at an angle  134  relative to a reference direction (e.g., the surface normal of the lenticular display or another desired reference direction). Each sub-pixel may have an associated direction  132  and angle  134 . The angle  134  (sometimes referred to as deflection angle  134 , horizontal deflection angle  134 , etc.) for each sub-pixel is stored in deflection measurements  130  in  FIG.  11   . The deflection measurements may be obtained during calibration operations during manufacturing electronic device  10 , as one example. The deflection measurements may be obtained using display calibration parameters such as lens pitch, pixel size, lens alignment, etc. 
       FIG.  12    shows how display  14  may intend to display a three-dimensional surface  136 . The target three-dimensional surface may be obtained, for example, from the three-dimensional image received at ray tracing circuitry  128 . Ray tracing circuitry  128  may, for each sub-pixel in display  14 , trace a ray  138  in the opposite direction of the outgoing direction  132  for that sub-pixel. In this way, ray tracing circuitry  128  simulates how a viewer perceives the light from that sub-pixel. Ray tracing circuitry  128  may, for each sub-pixel in display  14 , determine the point  140  on three-dimensional surface  136  that is intersected by ray  138 . Ray tracing circuitry  128  may also know the correlation between a location on the three-dimensional surface (of the given content)  136  and a corresponding location on the corresponding two-dimensional image (of the given content). 
     Ray tracing circuitry  128  outputs a display calibration map that includes, for each sub-pixel in display  14 , the location of a corresponding point on the two-dimensional image of the given content (e.g., the 2D image received by ray tracing circuitry  128  and pre-processing circuitry  104 ). Pixel mapping circuitry  114  subsequently uses the display calibration map to map the two-dimensional image that is intended to be displayed on display  14  to the pixel array of display  14 . For every sub-pixel of the display, pixel mapping circuitry  114  obtains a corresponding color value from the two-dimensional image that is intended to be displayed on display  14  (using the display calibration map with coordinates that identify, for each sub-pixel in display  14 , the location of a corresponding point on the two-dimensional image of the given content). Pixel mapping circuitry may perform the pixel mapping operations for each display frame (e.g., at a frequency that is equal to the display frame rate). 
     The display pipeline circuitry in  FIG.  11    includes pre-mapping processing circuitry  124  that processes the 2D image before pixel mapping and post-mapping processing circuitry  126  that processes the panel image after pixel mapping (similar to as in  FIG.  9   ). However, only one 2D image is processed by circuitry  104 ,  106 ,  108 , and  110  in  FIG.  11   . 
     Instead of binning pixels into a discrete number of viewing zones (e.g., 14 viewing zones) as in  FIG.  9   , the ray tracing in  FIG.  11    allows each sub-pixel to essentially be assigned a respective viewing zone. This allows the displayed images to be better optimized and mitigates crosstalk in the three-dimensional images displayed by lenticular display  14 . 
     A 2D image may be processed by pipeline circuitry  64  (e.g., pre-processing circuitry  104  receives a 2D image that is processed) at a rate that is equal to the display frame rate of display  14 . In contrast, the ray tracing operation performed by ray tracing circuitry  128  may be performed non-periodically or periodically at a second frequency that is lower than the display frame rate. In other words, ray tracing circuitry  128  outputs a new display calibration map based on an updated 3D image at the second frequency. The display frame rate may be at least 5× greater than the second frequency, at least 10× greater than the second frequency, at least 30× greater than the second frequency, at least 50× greater than the second frequency, at least 100× greater than the second frequency, etc. In other words, the ray tracing operation performed by ray tracing circuitry  128  (that generates a display calibration map) is asynchronous with the display frame rate. External stimuli (e.g., detected by one or more sensors in device  10 ) may trigger ray tracing circuitry  128  to generate a new display calibration map. 
     An example is described herein where display  14  includes a lenticular lens film  42  that spreads light across one dimension (e.g., across the horizontal dimension or the X-axis in  FIG.  5   ). This example is merely illustrative. In another possible arrangement, the display  14  may include a lens array that enables full parallax (e.g., both horizontal and vertical) in the display. The lens film over the display panel may include an array of lenses that each spread light both along the horizontal direction (e.g., the X-axis in  FIG.  5   ) and along the vertical direction (e.g., the Y-axis in  FIG.  5   ). One benefit of the ray tracing scheme described in connection with  FIGS.  11  and  12    is that computation demand is low for both a lens film that spreads light across one dimension and a lens film that spreads light across two dimensions. The computation demand for the ray tracing operation is determined by the number of sub-pixels and the number of ray tracing calculations that are needed. In other words, the computation demand for the ray tracing operation is not increased when display  14  has a lens film that spreads light across two dimensions. 
     In  FIGS.  9  and  11   , display pipeline circuitry  64  (content rendering circuitry  102 , pre-processing circuitry  104 , tone mapping circuitry  106 , ambient light adaptation circuitry  108 , calibration circuitry  110  (white point calibration circuitry in  FIG.  9    and primary display calibration circuitry in  FIG.  11   ), dithering circuitry  112 , pixel mapping circuitry  114 , color compensation circuitry  116 , border masking circuitry  118 , burn-in compensation circuitry  120 , panel response correction circuitry  122  and/or ray tracing circuitry  128 ) may sometimes be referred to as part of display  14  and/or may sometimes be referred to as control circuitry (e.g., part of control circuitry  16  in  FIG.  1   ). Each component in display pipeline circuitry  64  (e.g., content rendering circuitry  102 , pre-processing circuitry  104 , tone mapping circuitry  106 , ambient light adaptation circuitry  108 , calibration circuitry  110  (white point calibration circuitry in  FIG.  9    and primary display calibration circuitry in  FIG.  11   ), dithering circuitry  112 , pixel mapping circuitry  114 , color compensation circuitry  116 , border masking circuitry  118 , burn-in compensation circuitry  120 , panel response correction circuitry  122  and/or ray tracing circuitry  128 ) may be formed using one or more microprocessors, microcontrollers, digital signal processors, application specific integrated circuits, etc. 
     As described above, one aspect of the present technology is the gathering and use of information such as sensor information. The present disclosure contemplates that in some instances, data may be gathered that includes personal information data that uniquely identifies or can be used to contact or locate a specific person. Such personal information data can include demographic data, location-based data, telephone numbers, email addresses, twitter ID&#39;s, home addresses, data or records relating to a user&#39;s health or level of fitness (e.g., vital signs measurements, medication information, exercise information), date of birth, username, password, biometric information, or any other identifying or personal information. 
     The present disclosure recognizes that the use of such personal information, in the present technology, can be used to the benefit of users. For example, the personal information data can be used to deliver targeted content that is of greater interest to the user. Accordingly, use of such personal information data enables users to calculated control of the delivered content. Further, other uses for personal information data that benefit the user are also contemplated by the present disclosure. For instance, health and fitness data may be used to provide insights into a user&#39;s general wellness, or may be used as positive feedback to individuals using technology to pursue wellness goals. 
     The present disclosure contemplates that the entities responsible for the collection, analysis, disclosure, transfer, storage, or other use of such personal information data will comply with well-established privacy policies and/or privacy practices. In particular, such entities should implement and consistently use privacy policies and practices that are generally recognized as meeting or exceeding industry or governmental requirements for maintaining personal information data private and secure. Such policies should be easily accessible by users, and should be updated as the collection and/or use of data changes. Personal information from users should be collected for legitimate and reasonable uses of the entity and not shared or sold outside of those legitimate uses. Further, such collection/sharing should occur after receiving the informed consent of the users. Additionally, such entities should consider taking any needed steps for safeguarding and securing access to such personal information data and ensuring that others with access to the personal information data adhere to their privacy policies and procedures. Further, such entities can subject themselves to evaluation by third parties to certify their adherence to widely accepted privacy policies and practices. In addition, policies and practices should be adapted for the particular types of personal information data being collected and/or accessed and adapted to applicable laws and standards, including jurisdiction-specific considerations. For instance, in the United States, collection of or access to certain health data may be governed by federal and/or state laws, such as the Health Insurance Portability and Accountability Act (HIPAA), whereas health data in other countries may be subject to other regulations and policies and should be handled accordingly. Hence different privacy practices should be maintained for different personal data types in each country. 
     Despite the foregoing, the present disclosure also contemplates embodiments in which users selectively block the use of, or access to, personal information data. That is, the present disclosure contemplates that hardware and/or software elements can be provided to prevent or block access to such personal information data. For example, the present technology can be configured to allow users to select to “opt in” or “opt out” of participation in the collection of personal information data during registration for services or anytime thereafter. In another example, users can select not to provide certain types of user data. In yet another example, users can select to limit the length of time user-specific data is maintained. In addition to providing “opt in” and “opt out” options, the present disclosure contemplates providing notifications relating to the access or use of personal information. For instance, a user may be notified upon downloading an application (“app”) that their personal information data will be accessed and then reminded again just before personal information data is accessed by the app. 
     Moreover, it is the intent of the present disclosure that personal information data should be managed and handled in a way to minimize risks of unintentional or unauthorized access or use. Risk can be minimized by limiting the collection of data and deleting data once it is no longer needed. In addition, and when applicable, including in certain health related applications, data de-identification can be used to protect a user&#39;s privacy. De-identification may be facilitated, when appropriate, by removing specific identifiers (e.g., date of birth, etc.), controlling the amount or specificity of data stored (e.g., collecting location data at a city level rather than at an address level), controlling how data is stored (e.g., aggregating data across users), and/or other methods. 
     Therefore, although the present disclosure broadly covers use of information that may include personal information data to implement one or more various disclosed embodiments, the present disclosure also contemplates that the various embodiments can also be implemented without the need for accessing personal information data. That is, the various embodiments of the present technology are not rendered inoperable due to the lack of all or a portion of such personal information data. 
     The foregoing is merely illustrative and various modifications can be made to the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20220810
Publication Date: 20250114
Grant Date: 20250114
Priority Date: 20200811
Inventors: BACIM DE ARAUJO E SILVA, Felipe
KIM, SEUNG WOOK
ISKANDAR, EDWIN
Dudrenov, Pavel V
CORLEY, ZACHARY D
CHEN, HAO
CHOU, PING-YEN
Assignee: APPLE INC
CPC Classifications: [{"code": "H04N13/398", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/366", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04N13/305", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/327", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04N13/398", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/15", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/167", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/366", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04N13/305", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/327", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04N13/366", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04N13/398", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/305", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/167", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/15", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04N13/327", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 94212650