PATENT DOCUMENT

Publication Number: US-12150339-B2
Application Number: US-202318474118-A
Country: US
Kind Code: B2

Title: Electronic devices with light sensors and displays

Abstract:
An electronic device is provided with a display and a light sensor that receives light that passes through the display. The display includes features that increase the amount of light that passes through the display. The features may be translucency enhancement features that allow light to pass directly through the display onto a light sensor mounted behind the display or may include a light-guiding layer that guides light through the display onto a light sensor mounted along an edge of the display. The translucency enhancement features may be formed in a reflector layer or an electrode layer for the display. The translucency enhancement features may include microperforations in a reflector layer of the display, a light-filtering reflector layer of the display, or a reflector layer of the display that passes a portion of the light and reflects an additional portion of the light.

Claims:
What is claimed is: 
     
       1. An electronic device, comprising:
 a display having a cover layer, an array of pixels that displays images through the cover layer, and opaque structures; and 
 a light sensor mounted behind the array of pixels and configured to receive light that passes between the opaque structures of the display. 
 
     
     
       2. The electronic device defined in  claim 1  wherein the opaque structures comprise opaque conductive structures. 
     
     
       3. The electronic device defined in  claim 2  wherein the opaque conductive structures comprise metal traces. 
     
     
       4. The electronic device defined in  claim 3  wherein the metal traces are routed around a portion of the display through which the light passes to reach the light sensor. 
     
     
       5. The electronic device defined in  claim 3  wherein the metal traces have locally thinned portions that are thinner than other portions of the metal traces and wherein the light sensor is mounted behind the locally thinned portions. 
     
     
       6. The electronic device defined in  claim 1  wherein the light sensor is selected from the group consisting of: an ambient light sensor, a proximity sensor, an ultraviolet light sensor, an infrared light sensor, a thin-film solar cell, and a photoplethysmograph sensor. 
     
     
       7. The electronic device defined in  claim 1  wherein the array of pixels comprises a thin-film transistor array in an active area of the display and wherein the light sensor is mounted behind the thin-film transistor array. 
     
     
       8. The electronic device defined in  claim 1  wherein the light sensor is overlapped by a material that reflects visible light and transmits infrared light. 
     
     
       9. The electronic device defined in  claim 1  wherein the display has an opening through which the light passes to reach the light sensor. 
     
     
       10. The electronic device defined in  claim 9  wherein the opening is part of an array of microperforations in the display. 
     
     
       11. An electronic device, comprising:
 a display having an array of pixels on a substrate; 
 opaque conductive structures on the substrate; and 
 a light sensor mounted behind the array of pixels and configured to detect light that passes through a portion of the substrate that is between the opaque conductive structures. 
 
     
     
       12. The electronic device defined in  claim 11  wherein the opaque conductive structures comprise metal traces having locally thinned portions that are thinner than other portions of the metal traces, and wherein the light sensor is overlapped by the locally thinned portions. 
     
     
       13. The electronic device defined in  claim 11  wherein the opaque conductive structures comprise metal traces that are routed around the portion of the substrate through which the light passes. 
     
     
       14. The electronic device defined in  claim 11  wherein the light sensor is one of multiple light sensors that are mounted behind the array of pixels and that receive the light through the substrate. 
     
     
       15. The electronic device defined in  claim 11  wherein the light sensor is overlapped by a material that reflects visible light and transmits infrared light. 
     
     
       16. An electronic device, comprising:
 a display having an array of pixels that forms an active area and having first and second opaque structures separated by a gap; and 
 a light sensor mounted behind the active area of the display and configured to detect light that passes through the gap. 
 
     
     
       17. The electronic device defined in  claim 16  wherein the light sensor is selected from the group consisting of: an ambient light sensor, a proximity sensor, an ultraviolet light sensor, an infrared light sensor, a thin-film solar cell, and a photoplethysmograph sensor. 
     
     
       18. The electronic device defined in  claim 16  wherein the light sensor is overlapped by a material that reflects a first range of wavelengths and transmits a second range of wavelengths that is different from the first range of wavelengths. 
     
     
       19. The electronic device defined in  claim 16  wherein the first and second opaque structures comprise first and second metal traces. 
     
     
       20. The electronic device defined in  claim 19  wherein the first and second metal traces have locally thinned portions that are thinner than other portions of the metal traces and wherein the light sensor is overlapped by the locally thinned portions.

Description:
This application is a continuation of U.S. patent application Ser. No. 17/357,831, filed Jun. 24, 2021, which is a continuation of U.S. patent application Ser. No. 16/599,039, filed Oct. 10, 2019, now U.S. Pat. No. 11,050,044, which is a continuation of U.S. patent application Ser. No. 15/891,232, filed Feb. 7, 2018, now U.S. Pat. No. 10,446,800, which is a continuation of U.S. patent application Ser. No. 15/483,895, filed Apr. 10, 2017, now U.S. Pat. No. 9,947,901, which is a continuation of U.S. patent application Ser. No. 15/087,835, filed Mar. 31, 2016, now U.S. Pat. No. 9,620,571, which is a continuation of U.S. patent application Ser. No. 13/732,966, filed Jan. 2, 2013, now U.S. Pat. No. 9,310,843, all of which are hereby incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     This relates generally to electronic devices and, more particularly, to electronic devices with displays and light sensors. 
     Electronic devices often include displays. For example, cellular telephones and portable computers often include displays for presenting information to a user. 
     Electronic devices also often include light sensors. For example, an electronic device may include an ambient light sensor that senses the amount of light in the environment surrounding the device. The brightness of display images generated by the display is sometimes adjusted based on the amount of ambient light. For example, in bright sunlight, the display brightness may be increased and in a dark room, the display brightness can be decreased. 
     In a typical device, the display emits display light from a first side and has an opposing side that is opaque or reflective for preventing light from leaking into the device. These opaque display structures also block light that originates outside of the device such as ambient light from passing through the display. Additional space is therefore commonly provided within a device enclosure to accommodate a light sensor that receives light through a transparent portion of the enclosure. 
     This type of additional space for a common display and light sensor package can result in an undesirable increase in the size and thickness of the device. 
     It would therefore be desirable to be able to provide improved displays for electronic devices with light sensors and displays. 
     SUMMARY 
     An electronic device is provided with a display mounted in an electronic device housing. The electronic device is also provided with one or more light sensors that receive light through at least a portion of the display. 
     The light sensor may be implemented as an ambient light sensor, a proximity sensor, ultraviolet light sensor, infrared light sensor, thin-film solar cell, a photoplethysmograph, or other light sensor. 
     The display includes translucency enhancement features and/or light-guiding features that allow light that originates outside the device to pass through the display onto the light sensor. 
     The display may be an organic light-emitting diode display, a liquid crystal display or a display that incorporates other types of display pixel technology. 
     The translucency enhancement features may include a translucent reflective layer that reflects display light generated by the display while passing at least some ambient light, microperforations in one or more display layers that allow ambient light to pass through the display layers, modified display traces that allow light to pass onto the light sensor or other suitable translucency enhancement features that increase the transparency of the display in comparison with conventional displays. 
     The light-guiding features may include a light-guiding layer in the display that guides light to a light sensor that is mounted along an edge of the light-guiding layer. 
     The light sensor can be mounted behind the display and configured to receive light through the translucent display or the light sensor can be mounted along an edge of the display and receive light that is guided to the light sensor by the light-guiding layer of the display. 
     Further features, their nature and various advantages will be more apparent from the accompanying drawings and the following detailed description of the preferred embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG.  1    is a perspective view of an illustrative electronic device such as a laptop computer with a light sensor that receives light through a display in accordance with an embodiment. 
         FIG.  2    is a perspective view of an illustrative electronic device such as a handheld electronic device with a light sensor that receives light through a display in accordance with an embodiment. 
         FIG.  3    is a perspective view of an illustrative electronic device such as a tablet computer with a light sensor that receives light through a display in accordance with an embodiment. 
         FIG.  4    is a perspective view of an illustrative electronic device such as a computer display with a light sensor that receives light through a display in accordance with an embodiment. 
         FIG.  5    is a schematic diagram of an illustrative electronic device with a light sensor and a display in accordance with an embodiment. 
         FIG.  6    is a cross-sectional side view of a portion of an illustrative electronic device having a light sensor mounted behind an enhanced translucency display in accordance with an embodiment. 
         FIG.  7    is a cross-sectional side view of a portion of an illustrative electronic device having a light sensor mounted along an edge of a display that includes a light-guiding layer that guides light to the light sensor in accordance with an embodiment. 
         FIG.  8    is a diagram of an illustrative top-emission organic light-emitting diode display having translucency enhancement features that allow light to pass through the display onto a light sensor in accordance with an embodiment. 
         FIG.  9    is a diagram of an illustrative bottom-emission organic light-emitting diode display having translucency enhancement features that allow light to pass through the display onto a light sensor in accordance with an embodiment. 
         FIG.  10    is a diagram of an illustrative liquid crystal display having translucency enhancement features that allow light to pass through the display onto a light sensor in accordance with an embodiment. 
         FIG.  11    is a diagram of an illustrative reflective display layer having microperforations that enhance the translucency of the reflective display layer in accordance with an embodiment. 
         FIG.  12    is a diagram of an illustrative top-emission organic light-emitting diode display having a light-guiding layer that guides light onto a light sensor mounted along an edge of the display in accordance with an embodiment. 
         FIG.  13    is a diagram of an illustrative bottom-emission organic light-emitting diode display having a light-guiding layer that guides light onto a light sensor mounted along an edge of the display in accordance with an embodiment. 
         FIG.  14    is a diagram of an illustrative liquid crystal display having a light-guiding layer that guides light onto a light sensor mounted along an edge of the display in accordance with an embodiment. 
         FIG.  15    is a top view of an illustrative light-guiding layer showing how the light-guiding layer may guide light onto a light sensor mounted along an edge of the light-guiding layer in accordance with an embodiment. 
         FIG.  16    is a top view of an illustrative display circuitry layer showing how translucency enhancement features may include thinned conductive traces on the display circuitry layer in accordance with an embodiment. 
         FIG.  17    is a top view of an illustrative display circuitry layer showing how translucency enhancement features may include conductive traces having curved portions that deviate from a straight path to allow light to pass through the conductive traces onto a light sensor in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Electronic devices are provided with displays and light sensors. The display includes features that allow light to pass through the display onto the one or more light sensors. The features that allow light to pass through the display onto the one or more light sensors may include translucency enhancement features that enhance the translucency of the display and/or light-guiding structures that guide light through the display onto the light sensors. Illustrative electronic devices that have displays and light sensors are shown in  FIGS.  1 ,  2 ,  3 , and  4   . 
     Electronic device  10  of  FIG.  1    has the shape of a laptop computer and has upper housing  12 A and lower housing  12 B with components such as keyboard  16  and touchpad  18 . Device  10  has hinge structures  20  to allow upper housing  12 A to rotate in directions  22  about rotational axis  24  relative to lower housing  12 B. Display  14  such as an enhanced translucency display is mounted in upper housing  12 A. Upper housing  12 A, which may sometimes be referred to as a display housing or lid, is placed in a closed position by rotating upper housing  12 A towards lower housing  12 B about rotational axis  24 . Light sensors  40  such as ambient light sensors are mounted behind a portion of display  14 . Light sensors  40  may be ambient light sensors, proximity sensors, ultraviolet light sensors, infrared light sensors, thin-film solar cells, photoplethysmograph (PPG) sensors, or other light sensor that sense the amount of light falling on the light sensor through the translucent display  14 . Each light sensor  40  may include one or more photosensitive elements such as one or more photodiodes that generate electrical signals in response to incident light. Light sensors that are implemented as proximity sensors may also include a light-emitting component such as a light-emitting diode that emits light through a translucency enhancement feature and/or a light-guiding layer of the display. 
       FIG.  2    shows an illustrative configuration for electronic device  10  in which device  10  is implemented as a handheld device such as a cellular telephone, music player, gaming device, navigation unit, or other compact device. In this type of configuration for device  10 , housing  12  has opposing front and rear surfaces. Display  14  is mounted on a front face of housing  12 . Display  14  may have an exterior layer such as a rigid transparent layer that includes openings for components such as button  26  and speaker port  28 . 
     In the example of  FIG.  3   , electronic device  10  is a tablet computer. In electronic device  10  of  FIG.  3   , housing  12  has opposing planar front and rear surfaces. Display  14  is mounted on the front surface of housing  12 . As shown in  FIG.  3   , display  14  has an external layer with an opening to accommodate button  26 . 
       FIG.  4    shows an illustrative configuration for electronic device  10  in which device  10  is a computer display or a computer that has been integrated into a computer display. With this type of arrangement, housing  12  for device  10  is mounted on a support structure such as stand  27 . Display  14  is mounted on a front face of housing  12 . 
     In some configurations, peripheral portions of display  14  are provided with a partially or completely opaque masking layer. As shown in  FIGS.  1 ,  2 ,  3 , and  4   , display  14  may be characterized by a central active region such as active region AA in which an array of display pixels is used in displaying information for a user. An inactive region such as inactive border region IA surrounds active region AA. In the examples of  FIGS.  1 ,  2 ,  3 , and  4   , active region AA has a rectangular shape. Inactive region IA has a rectangular ring shape that surrounds active region AA (as an example). Portions of display  14  in inactive region IA may be covered with a partially opaque masking material such as a layer of black ink (e.g., a polymer filled with carbon black) or a layer of partially opaque metal. The masking layer helps hide components in the interior of device  10  in inactive region IA from view by a user. 
     In the examples of  FIGS.  1 ,  2 ,  3 , and  4   , four light sensors  40  are mounted behind portions of display  14  in active area AA and four additional ambient light sensors  40  are mounted behind portions of display  14  in inactive area IA. However, this is merely illustrative. If desired, device  10  may include more than four light sensors  40  in active area AA, less than four light sensors  40  in active area AA, more than four light sensors  40  in inactive area IA, less than four light sensors  40  in inactive area IA, a light sensor  40  that extends behind substantially all of active area AA, behind substantially all of inactive area IA, or behind substantially all of active area AA and inactive area AA. 
     Light sensors  40  that are located in inactive area IA may be mounted alongside an edge of display  14 . A light-guiding layer in display  14  may guide light from outside of device  10  to the light sensor mounted along the edge of the display. In this way, a light sensor is provided that can be mounted separately from an outer transparent layer of a device (i.e., a light sensor can be formed in the interior of the device). However, this is merely illustrative. If desired, light sensors  40  may be mounted directly behind display  14  in active area AA. 
     Display  14  includes translucency enhancement features that allow light to pass through display  14  onto the light sensor  40  that is mounted directly behind the display. 
     The configurations for device  10  that are shown in  FIGS.  1 ,  2 ,  3 , and  4    are merely illustrative. In general, electronic device  10  may be 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, or other wearable or miniature device, a television, 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, equipment that implements the functionality of two or more of these devices, or other electronic equipment. 
     Housing  12  of device  10 , which is sometimes referred to as a case, is formed of materials such as plastic, glass, ceramics, carbon-fiber composites and other fiber-based composites, metal (e.g., machined aluminum, stainless steel, or other metals), other materials, or a combination of these materials. Device  10  may be formed using a unibody construction in which most or all of housing  12  is formed from a single structural element (e.g., a piece of machined metal or a piece of molded plastic) or may be formed from multiple housing structures (e.g., outer housing structures that have been mounted to internal frame elements or other internal housing structures). 
     Display  14  may be a touch-sensitive display that includes a touch sensor or may be insensitive to touch. Touch sensors for display  14  may be formed from an array of capacitive touch sensor electrodes, a resistive touch array, touch sensor structures based on acoustic touch, optical touch, or force-based touch technologies, or other suitable touch sensor components. 
     Displays for device  10  may, in general, include image pixels formed from light-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells, electrowetting pixels, electrophoretic pixels, liquid crystal display (LCD) components, or other suitable image pixel structures. In some situations, it may be desirable to use OLED components to form display  14 , so configurations for display  14  in which display  14  is an organic light-emitting diode display are sometimes described herein as an example. Other types of display technology may be used in device  10 , if desired. 
     A schematic diagram of device  10  is shown in  FIG.  5   . As shown in  FIG.  5   , electronic device  10  includes control circuitry such as storage and processing circuitry  400 . Storage and processing circuitry  400  includes one or more different types of storage such as hard disk drive storage, nonvolatile memory (e.g., flash memory or other electrically-programmable-read-only memory), volatile memory (e.g., static or dynamic random-access-memory), etc. Processing circuitry in storage and processing circuitry  400  is used in controlling the operation of device  10 . The processing circuitry may be based on a processor such as a microprocessor and other integrated circuits. 
     With one suitable arrangement, storage and processing circuitry  400  is used to run software on device  10  such as internet browsing applications, email applications, media playback applications, operating system functions, software for capturing and processing images, software for implementing functions associated with gathering and processing sensor data, etc. 
     Input-output circuitry  32  is 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 circuitry  32  can include wired and wireless communications circuitry  34 . Communications circuitry  34  may include radio-frequency (RF) transceiver circuitry formed from one or more integrated circuits, power amplifier circuitry, low-noise input amplifiers, passive RF components, one or more antennas, and other circuitry for handling RF wireless signals. Wireless signals can also be sent using light (e.g., using infrared communications). 
     Input-output circuitry  32  of  FIG.  5    includes input-output devices  36  such as buttons, joysticks, click wheels, scrolling wheels, a touch screen such as translucent display  14 , other touch sensors such as track pads or touch-sensor-based buttons, vibrators, audio components such as microphones and speakers, image capture devices such as a camera module having an image sensor and a corresponding lens system, keyboards, status-indicator lights, tone generators, key pads, and other equipment for gathering input from a user or other external source and/or generating output for a user. 
     Sensors  38  of  FIG.  5    include a light sensor such as an ambient light sensor for gathering information on ambient light levels. Sensors  38  also include other light sensor components such as proximity sensor components. Proximity sensor components in device  10  can include capacitive proximity sensor components, infrared-light-based proximity sensor components, proximity sensor components based on acoustic signaling schemes, solar cell light sensor technology, or other proximity sensor equipment. Sensors  38  may also include a pressure sensor, a temperature sensor, an accelerometer, a gyroscope, and other circuitry for making measurements of the environment surrounding device  10 . 
     It can be challenging to mount electrical components such as the components of  FIG.  5    within an electronic device. To facilitate mounting of components in housing  12  of device  10 , sensors  38  may be configured to receive light through a portion of a display having translucency enhancement features and/or light-guiding features that increase the amount of light that passes through the display onto the light sensor. 
     Storage and processing circuitry  400  samples voltages, electrical charges, or other electrical light sensor signals from light sensors  40  of sensors  38 . Storage and processing circuitry  400  converts the sampled signals into ambient light intensities. Storage and processing circuitry  400  controls other aspects of the operation of device  10  using the converted ambient light intensities. For example, storage and processing circuitry can increase or decrease the display light from the device display based on the ambient light intensity. 
       FIG.  6    is a cross-sectional view of a portion of device  10  with a light sensor such as light sensor  40  that is mounted adjacent to inner surface  77  of display  14  having translucency enhancement features  43 . Device  10  also includes a circuitry such as printed circuit board  42  and a flexible printed circuit  44  that electrically couples light sensor  40  to printed circuit board (PCB)  42 . Circuitry associated with printed circuit board  42  (e.g., internal circuitry, circuitry on a surface of PCB  42 , and/or integrated circuitry such as circuit components  48  mounted to a surface of PCB  42 ) controls the operation of display  14  and light sensor  40 . PCB  42  and components  48  may, for example, form some or all of storage and processing circuitry  400  of  FIG.  5   . 
     Light signals such as ambient light intensity signals gathered using light sensor  40  in response to light  45  are routed to printed circuit board  42  through flexible printed circuit  44 . Flexible printed circuit  44  is attached to a portion of sensor  40  using electrical coupling material (e.g., anisotropic conductive film (ACF), solder, or other electrically conductive adhesive material). An opposing end of flexible printed circuit  44  is attached to a portion of PCB  42  using electrical coupling material (e.g., anisotropic conductive film (ACF), solder, or other electrically conductive adhesive materials, or mechanical connector structures). 
     Display  14  may include multiple display layers such as layers  14 A and  14 B. Display layer  14 B may include a transparent cover layer (e.g., a sheet of transparent plastic or glass) and, if desired, a touch-sensitive layer and/or other display layers such as protective films, anti-reflection coatings, anti-glare coatings, anti-smudge coatings, etc. A touch-sensitive layer may include transparent electrodes formed from, for example, indium tin oxide or other transparent or translucent conductive material. Touch-sensor circuitry may include capacitive touch-sensor technology, resistive touch-sensor technology, force-based touch-sensor technology or other touch-sensor technology for gathering user touch input. 
     Display layer  14 A may include multiple layers for generating display images for display  14 . Display layer  14 A may include image generating structures such as light-emitting diodes (LEDs), organic LEDs (OLEDs), plasma cells, electrowetting pixels, electrophoretic pixels, liquid crystal display (LCD) components, backlight structures, or other suitable image pixel structures. 
     As shown in  FIG.  6   , translucency enhancement features  43  may be features of display  14  that allow light  45  from outside of device  10  to be transmitted directly through display  14  onto light sensor  40 . Translucency enhancement features of this type may allow less than 1 percent, less than 0.5 percent, less than 0.2 percent, less than 0.05 percent, less than 0.02 percent, greater than 0.01 percent, greater than 0.02 percent, greater than 0.1 percent between 0.05 and 1 percent, between percent and 3 percent or less than 5 percent of light  45  to pass through features  43 . 
     Translucency enhancement features  43  may include openings in a display layer (e.g., microperforations in a reflective layer of a display), a partially transmissive reflector layer (e.g., a reflective layer that reflects a portion of the light that is incident on it while passing a relatively smaller portion of the incident light or a reflective layer that reflects light such as display light  50  having a first set of wavelengths such as visible wavelengths while passing light of a second, different set of wavelengths such as infrared and/or ultraviolet wavelengths), or other structures that allow a relatively larger portion of incident light to pass through as compared with conventional displays. 
     Translucency enhancement features  43  may be formed in localized portions of display  14  as in the example of  FIG.  6    or may extend across some or all of display  14 . In configurations in which features  43  are formed in localized portions of display  14 , a larger fraction of ambient light  45  may pass through features  43  than the fraction that passes through other portions of display  14 . In configurations in which features  43  extend across substantially all of display  14 , display  14  may be a translucent display that allows a measurable fraction of external light  45  to pass through the display onto a sensor such as sensor  40 . 
     The translucency enhancement features of  FIG.  6    are merely illustrative. As shown in  FIG.  7   , display  14  may be provided with one or more light-guiding structures such as light-guiding layer  52  of display  14  that guide light through at least a portion of the display to a light sensor such as light sensor  40 . In the example of  FIG.  7   , light sensor  40  is mounted adjacent to edge  120  of display layers  14 A. In this type of configuration, light  45  enters display  14  through outer surface  56  and is redirected along layer  52  onto sensor  40 . Light-guiding layer  52  may include wave-guide structures, light-focusing structures, optical films such as wave-guide films or film stacks that redirect light based on reflections at refractive index changes between films in the stack, beam steering films, geometric light-guiding structures, corrugated light-guiding structures, or other light-guiding structures. 
     As examples, layer  52  may include a first planar layer of transparent material and a curved layer of transparent material attached to the planar layer that guides light in a direction parallel to the planar layer or layer  52  may include a pair of transparent layers having planar outer surfaces and interfacing corrugated interior surfaces that guide light in a direction parallel to the planar outer surfaces using reflections at the interfacing corrugated interior surfaces. 
       FIGS.  8 ,  9 ,  10 , and  11    show examples of arrangements in which display  14  includes translucency enhancement features that allow light from outside of device  10  to be transmitted directly through display  14  onto a light sensor.  FIGS.  12 ,  13   , and  14  show examples of arrangements in which display  14  includes a light-guiding layer that guides light through the display to a light sensor that mounted adjacent the display. 
       FIG.  8    is a cross-sectional view of a light sensor  40  that receives light  45  through display layers  14 A that are implemented as a top-emission organic light emitting diode (OLED) display.  FIG.  9    is a cross-sectional view of a light sensor  40  that that receives light  45  through display layers  14 A that are implemented as a bottom-emission organic light emitting diode (OLED) display.  FIG.  10    is a cross-sectional view of a light sensor  40  that that receives light  45  through display layers  14 A that are implemented as a liquid crystal display (LCD). 
     In a configuration for display  14  of the type shown in  FIG.  8   , layers  14 A include an outer layer such as layer  60 . Outer layer  60  may include a protective film and/or one or more light-polarizing layers such as a linear polarizer and/or a circular polarizer. Layers  14 A include a layer of organic light-emitting material such as organic emissive layer  66  that is interposed between electrode layers  64  and  68 . Electrode layer  64  may be a partially transmissive electrode layer such as a cathode layer that allows display light  50  to pass through the electrodes. 
     Organic emissive layer  66  may be formed from organic plastics such as polyfluorene or other organic emissive materials. Electrode layer  64  is covered by barrier layer  62 . Barrier layer  62  may be formed from a layer of plastic, a glass layer, a thin-film encapsulation layer formed from a material such as silicon nitride, a layered stack of alternating polymer and ceramic materials, or other suitable material for forming a barrier layer that protects organic emissive layer  66  from environmental exposure by preventing water and oxygen from reaching organic emissive materials within layer  66 . 
     Electrode layer  68  may be a reflective or partially reflective electrode layer such an anode layer. An array of thin-film transistors (TFTs) may be formed throughout some or all of layer  68 . The thin-film transistors may be formed from semiconductors such as amorphous silicon, polysilicon, or compound semiconductors (as examples). Layer  68  may include reflective material or opaque masking material (e.g., black ink) on thin film-transistors in layer  68  that helps prevent the thin-film transistors from being viewed by a viewer such as viewer  80  viewing display  14  in direction  82 . If desired, a layer of transparent dielectric material such as dielectric layer  70  may be formed on a surface of electrode layer  68 . Dielectric layer  70  may help planarize the surface of electrode layer  68  or may be a dielectric spacer layer for display  14 . However, this is merely illustrative. If desired, display layer  14 A may be formed without dielectric layer  70 . 
     An additional barrier layer such as barrier layer  72  is formed over electrode layer  68  and dielectric layer  70 . In configurations in which layers  14 A are provided without dielectric layer  70 , barrier layer  72  may be formed directly on electrode layer  68 . Barrier layer  72  may be formed from a layer of metal foil, metal foil covered with plastic, other metal structures, a glass layer, a thin-film encapsulation layer formed from a material such as silicon nitride, a layered stack of alternating polymer and ceramic materials, or other suitable material for encapsulating organic emissive layer  66  and electrode layer  68 . 
     Substrate layer  74  (e.g., a layer of plastic or glass) is attached to barrier layer  72 . A reflective layer such as reflector  76  may be attached to substrate  74 . Reflective layer  76  reflects light that is emitted from organic emissive layer  66  in the direction of reflector  76  back out of display layers  14 A to be viewed by a viewer such as viewer  80 . 
     As shown in  FIG.  8   , one or more light sensors  40  may be mounted adjacent to a surface such as surface  77  of reflector  76 . Light  45  such as ambient light passes through translucency enhancement features  43  in display layer  14 A onto light sensors  40 . In the example of  FIG.  8   , translucency enhancement features  43  are formed in reflector layer  76  and electrode/TFT layer  68 . However, this is merely illustrative. If desired, display  14  may include translucency enhancement features in any location in display  14 . 
     Translucency enhancement features  43  in reflector layer  76  may include openings such as microperforations (i.e., perforations that allow light to pass through but that are too small to be seen with the human eye when no light shines through the perforations) or regions of modified transparency in reflector layer  76 . For example, translucency enhancement features  43  may be portions of reflector  76  that are formed form translucent material that reflects a portion of the light that is incident on it while passing a relatively smaller portion of the incident light or features  43  may be portions of reflector  76  that are formed from a material that reflects light such as display light  50  having a first set of wavelengths such as visible wavelengths while passing light of a second, different set of wavelengths such as infrared and/or ultraviolet wavelengths (as examples). 
     Translucency enhancement features  43  may be formed in localized portions of reflector  76  as in the example of  FIG.  8    or may extend across some or all of reflector  76  (e.g., reflector  76  may be substantially all formed from a material that is partially translucent or that allows light having a given range of wavelengths such as infrared wavelengths and/or ultraviolet wavelengths to pass while reflecting light of other wavelengths). 
     Translucency enhancement features in electrode/TFT layer  68  may include microperforations in layer  68 , portions of layer  68  that are formed from a translucent material, portions of layer  68  that are formed from a material that passes light having a given range of wavelengths (e.g., infrared wavelengths and/or ultraviolet wavelengths) while reflecting light of other wavelengths, or may include portions of opaque conductive structures such as conductive traces that are modified to allow light to pass through or between the conductive traces. Modified conductive traces may include locally thinned conductive traces or rerouted conductive traces (as examples). As shown in  FIG.  8   , features  43  in layer  68  may be aligned with features  43  in layer  76  so that light such as light  45  may pass through the aligned translucency enhancement features in multiple display layers onto one or more of light sensors  40 . 
     Light absorbing material  78  is formed on surface  77  of reflector  76 . Light absorbing material may include light-absorbing ink such as infrared absorbing ink that prevents light from reflecting from sensors  40  back through display layers  14 A. Material  78  on surface  77  helps prevent user  80  from viewing light sensor  40 . Material  78  may include one or more openings  79  aligned with features  43  that allow light to pass through the openings onto sensors  40 . 
     In a configuration for display  14  of the type shown in  FIG.  9   , light sensors  40  receive light  45  through translucency enhancement features  43  in a bottom-emission light emitting diode display (i.e., an OLED display that emits light through a substrate layer). In the example of  FIG.  9   , a first surface of substrate layer  74  is attached to outer layer  60  and a second, opposing surface of substrate  74  is attached to barrier layer  72 . Optional dielectric layer  70  is attached to barrier layer  72  and electrode layer  64  is attached to dielectric layer  70 . In configurations in which display layers  14 A are provided without dielectric layer  70 , barrier layer  72  may be formed directly on electrode layer  64 . Organic emissive layer  66  is sandwiched between electrode layers  64  and  68  and emits display light  50  through electrode layer  64  and other display layers  14 A. Barrier layer  62  is formed on electrode layer  68  and reflector layer  76  is attached to barrier layer  62 . 
     One or more light sensors  40  is mounted adjacent to surface  77  of reflector  76  and receives light such as light  45  through translucency enhancement features  43  in reflector layer  76 , electrode layer  68 , and/or other layers of display layers  14 A. 
     In a configuration for display  14  of the type shown in  FIG.  10   , light sensors  40  receive light  45  through translucency enhancement features  43  in a liquid crystal display (LCD) formed from liquid crystal display cell  84  and backlight structures  86 . Liquid crystal layer  92  of LCD cell  84  is formed between color filter layer  90  and thin-film transistor layer  94 . Layers  90  and  94  may be formed on a transparent substrate such as a sheet of glass. Liquid crystal layer  92 , color filter layer  90 , and thin-film transistor layer  94  are sandwiched between light polarizing layers such as upper polarizer  88  and lower polarizer  96 . 
     Backlight structures  86  may include a light guide plate such as light guide plate  100 . Light guide plate  100  may be formed from a transparent material such as clear glass or plastic that guides light using internal reflections within plate  100 . During operation of backlight structures  86 , a light source such as light source  102  may generate light  103 . Light source  102  may be, for example, an array of light-emitting diodes. 
     Light  103  from light source  102  may be coupled into an edge of light guide plate  100  and may be distributed in dimensions X and Y throughout light guide plate  100  due to the principal of total internal reflection. Light guide plate  100  may include light-scattering features such as pits or bumps. The light-scattering features may be located on an upper surface and/or on an opposing lower surface of light guide plate  100 . 
     Light  103  that scatters upwards in direction Z from light guide plate  100  may serve as display light  50  for display  14 . Light  103  that scatters downwards may be reflected back in the upwards direction by reflector  76 . Reflector  76  may be formed from a reflective material such as metal, a layer of white plastic or may be formed from a translucent material that allows some of light  45  to pass while reflecting other portions of light  45 . 
     Backlight structures  86  may include optical films  98  (e.g., diffuser layers, compensation films for enhancing off-axis viewing, and brightness enhancement films (also sometimes referred to as turning films) for collimating backlight). 
     Light sensor  40  may be attached to interior surface  77  of a reflector such as reflector  76  that is implemented in backlight unit  86  and may receive ambient light through upper polarizer  88 , color filter layer  90 , liquid crystal layer  92 , thin-film transistor layer  94 , lower polarizer layer  96 , and backlight unit  86 . Backlight unit  86 , thin-film transistor layer  94  and/or other portions of a liquid crystal display of the type shown in  FIG.  10    may include features  43  that enhance the transmission of light  45  through display layers  14 A to sensor  40 . 
     As described above in connection with  FIG.  8   , translucency enhancement features  43  in reflector layer  76  may include openings such as microperforations (i.e., perforations that allow light to pass through but that are too small to be seen with the human eye when light does not shine through the perforations) or regions of modified transparency in reflector layer  76 . 
     Translucency enhancement features  43  may be formed in localized portions of reflector  76  or may extend across some or all of reflector  76 . 
     Translucency enhancement features  43  in thin-film transistor layer  94  may include microperforations in layer  94 , partially translucent portions of layer  94 , portions of layer  94  that pass light having a given range of wavelengths (e.g., infrared and/or ultraviolet wavelengths) while reflecting light of other wavelengths (e.g., visible wavelengths), or may include portions of opaque conductive structures such as conductive traces that are modified to allow light to pass through the conductive traces. Modified conductive traces may include locally thinned conductive traces or rerouted conductive traces (as examples). Features  43  in layer  94  may be aligned with features  43  in layer  76  so that light such as light  45  may pass through the aligned translucency enhancement features onto one or more of light sensors  40 . 
       FIG.  11    is cross-sectional view of a portion of reflector  76  showing how translucency enhancement features  43  may be formed from openings such as microperforations  104  in reflector  76 . Microperforations  104  pass through reflector  76  from a first surface to an opposing second surface of reflector  76 . Openings  104  may include openings in masking material  78 . Microperforations  104  may be laser-drilled openings in layer  76  (as an example). If desired, microperforations such as microperforations  104  may be formed in other layers of display  14  (e.g., one or more additional display layers of display layers  14 A and/or one or more of display layers  14 B). Microperforations  104  may be formed in a localized portion of reflector  76  or may be formed across substantially all of reflector  76 . 
       FIG.  12    is a cross-sectional view of a light sensor  40  that that receives light  45  through a light-guiding layer of display layers  14 A that are implemented as a top-emission OLED display.  FIG.  13    is a cross-sectional view of a light sensor  40  that that receives light  45  through a light-guiding layer of display layers  14 A that are implemented as a bottom-emission OLED display.  FIG.  14    is a cross-sectional view of a light sensor  40  that that receives light  45  through a light-guiding layer of display layers  14 A that are implemented as an LCD display. 
     In a configuration for display  14  of the type shown in  FIG.  12   , a top-emission OLED display of the type shown in  FIG.  8    is provided with an additional layer such as light-guide layer  52 . Light-guide layer  52  is attached to barrier layer  72  using a layer of transparent adhesive such as optically clear adhesive layer  108 . Substrate  74  is attached to an opposing surface of light-guide layer  52  and to reflective layer  76 . Light  45  that passes through organic emissive layer  66  and enters light-guide layer  52  is guided within layer  52  (e.g., along the x-y plane of  FIG.  12   ) onto a light sensor  40  that is mounted adjacent to edge  120  of display layers  14 A (e.g., adjacent to an edge of light-guide layer  52 ). 
     During manufacturing and assembly operations, a temporary substrate such as a plastic sheet may be attached to display layers  14 A at location  124 . After assembly of display layers  60 ,  62 ,  64 ,  66 ,  68 ,  70 , and  72  on the temporary substrate, the temporary substrate may be removed and light-guide layer  52  may be attached at location  124  using adhesive  108 . 
     In a configuration for display  14  of the type shown in  FIG.  13   , a bottom-emission OLED display of the type shown in  FIG.  9    is provided with an additional layer such as light-guide layer  52 . Light-guide layer  52  is attached to barrier layer  72  using a layer of transparent adhesive such as optically clear adhesive layer  108 . Substrate  74  is attached to an opposing surface of light-guide layer  52  and to outer layer  60 . Light  45  that enters light-guide layer  52  is guided within layer  52  (along the x-y plane of  FIG.  13   ) onto a light sensor  40  that is mounted adjacent to edge  120  of display layers  14 A (e.g., adjacent to an edge of light-guide layer  52 ). Display light  50  passes through light-guide layer  52  and out of display layers  14 A to be viewed by viewer  80  in direction  82 . 
     In a configuration for display  14  of the type shown in  FIG.  14   , an LCD display of the type shown in  FIG.  10    is provided with an additional layer such as light-guide layer  52 . Light-guide layer  52  is interposed between LCD cell  84  and backlight structures  86 . However, this is merely illustrative. If desired, light-guide layer  52  may be formed behind backlight unit  86  or may be formed between two other layers of LCD cell  84  or backlight structures  86 . In the example of  FIG.  14   , light that enters light-guide layer  52  after passing through LCD cell  84  is guided within layer  52  (e.g., along the x-y plane of  FIG.  14   ) onto a light sensor  40  that is mounted adjacent to edge  120  of display layers  14 A (e.g., adjacent to an edge of light-guide layer  52 ). Display light  50  that is generated by backlight structures  86  passes through light-guide layer  52 , through LCD cell  84 , and out of display layers  14 A to be viewed by viewer  80  in direction  82 . 
     In the examples of  FIGS.  12 ,  13 , and  14   , device  10  includes a light sensor mounted along edge  120  of display  14  that receives light through light-guide layer  52 , and two light sensors mounted adjacent to interior surface  77  of display  14  that receive light through translucency enhancement features  43 . However this is merely illustrative. In various other possible combinations, device  10  may be provided with a single light sensor mounted adjacent to surface  77 , three or more light sensors mounted adjacent to surface  77  or no light sensors mounted adjacent to surface  77 . Device  10  may include more than one light sensor mounted adjacent to edge  120  or may be provided without any light sensors mounted adjacent to edge  120 . 
     In order to minimize the effect of display light  50  on light detection operations using light sensors  40 , the light sensors may be provided with light-filtering structures such as light-filtering films that prevent display light from reaching the sensors, light sensor data may be gathered during blanking periods in which display  14  is not generating display light, or display light signals may be removed from light sensor data using software applications that access stored display light data associated with known features of the display light (e.g., known display light wavelengths, known display light intensities or known display light emission cycles). 
       FIG.  15    is a top view of a light guide layer such as light-guide layer  52  (e.g., light-guide layer  52  of any of  FIG.  7 ,  12 ,  13   , or  14 ). In the example of  FIG.  15   , light-guide layer  52  includes internal light guiding structures  128  (e.g., geometric features, corrugated features, etc.) that guide light that is incident on light-guide layer  52  along directions  130  onto light sensor  40  mounted along edge  120 . Light-guide layer  52  may include a coating layer  125  on edge  120  that prevents light from exiting light-guide layer  52 . Coating  125  may have an opening such as opening  126  that allows light to exit from edge  120  through opening  126  onto light sensor  40 . 
       FIG.  16    is a top view of a portion of a display circuitry layer having translucency enhancement features formed from modified conductive traces on the circuitry layer. Display circuitry layer  110  may be a portion of electrode/TFT layer  68  of any of  FIG.  8 ,  9 ,  12   , or  13 , may be a portion of TFT layer  94  of either of  FIG.  10  or  14   , or may be any other layer of display  14  having conductive traces such as traces  112 . Conductive traces  112  may be formed from opaque conductive material such as metal (e.g., copper). 
     In the example of  FIG.  16   , translucency enhancement features  43  are formed from thinned portions  114  of selected conductive traces  112 . Thinned portions  114  are formed over light sensor  40  so that light may pass between thinned portions  114  onto sensor  40 . Layer  110  includes conductive traces  112  having thinned portions  114  and conductive traces  112  that have a substantially constant thickness along the length of the trace. 
     The modified conductive traces of  FIG.  16    are merely illustrative. If desired, conductive traces on layer  110  may be modified in other ways to allow light to pass through conductive traces  112  onto light sensor  40 . 
     In the example of  FIG.  17   , traces  112  include curved portions  116  that reroute the traces on layer  110  so that the traces avoid overlapping light sensor  40 . In this way, curved portions  116  of layer  110  allow light to pass between curved portions  116  of traces  112  onto light sensor  40 . Layer  110  includes conductive traces  112  having curved portions  116  and conductive traces  112  that extend along substantially straight paths on layer  110 . 
     The foregoing is merely illustrative and various modifications can be made by those skilled in the art without departing from the scope and spirit of the described embodiments. The foregoing embodiments may be implemented individually or in any combination.

Metadata:
Filing Date: 20230925
Publication Date: 20241119
Grant Date: 20241119
Priority Date: 20130102
Inventors: SHEDLETSKY, ANNA-KATRINA
DRZAIC, PAUL S.
DE JONG, ERIK G.
ROTHKOPF, FLETCHER R.
Assignee: APPLE INC
CPC Classifications: [{"code": "G02F1/13318", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F1/1637", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K2102/3026", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/60", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K59/13", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/856", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/844", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/828", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/818", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/86", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/11", "inventive": true, "first": false, "tree": "[]"}, {"code": "G02F1/13312", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/8791", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/80524", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/80518", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/878", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/873", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K50/865", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F1/1637", "inventive": true, "first": true, "tree": "[]"}, {"code": "H10K2102/3026", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02F1/13318", "inventive": false, "first": false, "tree": "[]"}, {"code": "G02F1/13312", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K59/60", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K59/13", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/86", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/856", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/844", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/828", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/818", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/11", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F1/1637", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/865", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 49943513