PATENT DOCUMENT

Publication Number: US-12170271-B2
Application Number: US-202117398952-A
Country: US
Kind Code: B2

Title: Embedded optical sensors in a micro-led display

Abstract:
A micro-light-emitting diode (LED) display includes a number of micro-LED pixel elements and multiple optical sensors integrated with the micro-LED pixel elements. A transparent conductor layer is disposed over the micro-LED pixel elements and optical sensors.

Claims:
What is claimed is: 
     
       1. A micro-light-emitting diode (LED) display comprising:
 a plurality of micro-LED pixel elements; 
 a plurality of optical sensors integrated with the plurality of micro-LED pixel elements; 
 a transparent conductor layer disposed over the plurality of micro-LED pixel elements and the plurality of optical sensors; and 
 a plurality of collimators, wherein a collimator of the plurality of collimators is formed of one or more pinholes. 
 
     
     
       2. The micro-LED display of  claim 1 , wherein a micro-LED pixel element of the plurality of micro-LED pixel elements and an optical sensor of the plurality of optical sensors share a micro-driver circuit that is configured to provide a current for the micro-LED pixel element and bias voltage and readout circuitry for the optical sensor. 
     
     
       3. The micro-LED display of  claim 1 , further comprising a passivation layer isolating a micro-LED pixel element of the plurality of micro-LED pixel elements from an optical sensor of the plurality of optical sensors. 
     
     
       4. The micro-LED display of  claim 1 , wherein at least one set of optical sensors of the plurality of optical sensors is disposed in between four blocks of red-green-blue (RGB) pixel elements, wherein each block of RGB pixels includes a set of primary RGB pixel elements and a set of redundant RGB pixel elements. 
     
     
       5. The micro-LED display of  claim 1 , wherein at least one set of optical sensors of the plurality of optical sensors is disposed on one side of four blocks of RGB pixel elements, wherein each block of RGB pixels includes a set of primary RGB pixel elements and a set of redundant RGB pixel elements. 
     
     
       6. The micro-LED display of  claim 1 , wherein an optical sensor of the plurality of optical sensors is disposed on one side of a block of RGB pixel elements, wherein the block of RGB pixels includes a set of primary RGB pixel elements and a set of redundant RGB pixel elements. 
     
     
       7. The micro-LED display of  claim 1 , wherein the plurality of optical sensors are embedded in a micro-LED panel of the micro-LED display, and wherein the micro-LED panel includes the plurality of micro-LED pixel elements. 
     
     
       8. The micro-LED display of  claim 1 , wherein the plurality of optical sensors are embedded in a micro-driver layer of the micro-LED display, and wherein the micro-driver layer includes a plurality of micro-driver circuits. 
     
     
       9. The micro-LED display of  claim 1 , wherein the plurality of optical sensors are embedded in a sensor layer of the micro-LED display, and wherein the sensor layer is disposed underneath a micro-driver layer, and wherein the micro-driver layer includes a plurality of micro-driver circuits. 
     
     
       10. The micro-LED display of  claim 1 , wherein an optical sensor of the plurality of optical sensors is realized using one of a list of options, the list of options including an organic photodiode (OPD), a Si PD, a micro-LED, dedicated silicon-based photodetectors or quantum dot (QD) material. 
     
     
       11. The micro-LED display of  claim 1 , wherein a pinhole of the one or more pinholes is formed by two black matrix (BM) layers separated by a transparent spacer layer. 
     
     
       12. The micro-LED display of  claim 1 , wherein a pinhole of the one or more pinholes is formed by a pinhole mask layer and a microlens separated from the pinhole mask layer by a transparent spacer layer. 
     
     
       13. An electronic device comprising:
 a processor; and 
 a micro-LED display comprising:
 a plurality of micro-LED pixel elements; 
 a plurality of optical sensors integrated with the plurality of micro-LED pixel elements; 
 a transparent conductor layer disposed over the plurality of micro-LED pixel elements and the plurality of optical sensors; and 
 a readout circuit controlled by the processor and configured to read out the plurality of optical sensors; and 
 
 a plurality of collimators, wherein a collimator of the plurality of collimators is formed of one or more pinholes. 
 
     
     
       14. The electronic device of  claim 13 , wherein at least one set of optical sensors of the plurality of optical sensors is disposed in between or on one side of four blocks of RGB pixel elements. 
     
     
       15. The electronic device of  claim 13 , wherein an optical sensor of the plurality of optical sensors is implemented using one of a list of options, the list of options including an OPD, a Si PD, a micro-LED, dedicated silicon-based photodetector or QD material. 
     
     
       16. The electronic device of  claim 13 , wherein the plurality of optical sensors are embedded in a micro-LED panel or in a micro-driver layer of the micro-LED display, and wherein the micro-LED panel includes the plurality of micro-LED pixel elements, and the micro-driver layer includes a plurality of micro-driver circuits. 
     
     
       17. The electronic device of  claim 13 , wherein the plurality of optical sensors are embedded in a sensor layer underneath a micro-driver layer, and wherein the micro-driver layer includes a plurality of micro-driver circuits. 
     
     
       18. The electronic device of  claim 13 , wherein a pinhole of the one or more pinholes is formed by two BM layers separated by a transparent spacer layer or a pinhole mask layer and a microlens separated from the pinhole mask layer by a transparent spacer layer. 
     
     
       19. A display apparatus comprising:
 a display panel; 
 a micro-LED panel including a plurality of micro-LED pixel elements; 
 a micro-driver layer including a plurality of driver circuits; and 
 a plurality of optical sensors embedded in one of the micro-LED panel or micro-driver layer, wherein at least one set of optical sensors of the plurality of optical sensors is disposed in between or on one side of four blocks of RGB pixel elements. 
 
     
     
       20. The display apparatus of  claim 19 , wherein an optical sensor of the plurality of optical sensors is implemented using one of a list of options, the list of options including an OPD, a Si PD, a micro-LED or QD material. 
     
     
       21. The display apparatus of  claim 19 , wherein at least some of the micro-LED pixel elements are configured to be used as photodetectors.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 63/073,885, entitled “EMBEDDED OPTICAL SENSORS IN A MICRO-LED DISPLAY,” filed Sep. 2, 2020, the entirety of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present description relates generally to sensor technology, and more particularly to embedded optical sensors in a micro-light-emitting diode (micro-LED) display. 
     BACKGROUND 
     Micro-light-emitting diode (micro-LED) is a technology used in displays consisting of an array of microscopic LEDs of different colors, such as red, green and blue. Competing with organic-LED (OLED) and quantum-dot LED (QLED) display technology, micro-LED is considered by some to be the superior technology, which have used in a super large (e.g., 146-inch) micro-LED television (TV) prototype. Similar to OLED, micro-LED is an emissive display technology where the picture elements, also known as pixels, are also the light source. This means emissive display technologies don&#39;t require a separate backlight layer, which allows displays to be thinner than liquid-crystal display (LCD). Unlike OLED, micro-LED doesn&#39;t require an encapsulation layer making it even thinner. QLED is not an emissive display type as LEDs are only used to light quantum dots. Both OLED and micro-LED have fast response times. 
     Unlike OLEDs, micro-LEDs are not made with organic compounds, but with the more traditional indium gallium nitride (InGaN)-based LEDs that have been shrunk down. The use of InGaN LEDs results in micro-LED displays having greater brightness without degradation and burn-in, which is possible on OLED and an upside of QLED displays. While LED-backlit displays, commonly referred to as LED displays, can do regional dimming of LEDs for better contrast, they don&#39;t have the inherent high contrast or response time of the true emissive display technologies such as OLED and micro-LED. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Certain features of the subject technology are set forth in the appended claims. However, for purposes of explanation, several embodiments of the subject technology are set forth in the following figures. 
         FIG.  1    is a schematic diagram illustrating a cross-sectional view of a section of an exemplary micro-light-emitting diode (micro-LED) display with embedded optical sensor, in accordance with one or more aspects of the subject technology. 
         FIG.  2    is a schematic diagram illustrating a shared driver of a micro-LED and an embedded optical sensor of a micro-LED display, in accordance with one or more aspects of the subject technology. 
         FIGS.  3 A,  3 B and  3 C  are diagrams illustrating various example configurations for embedding optical sensors within a micro-LED display, in accordance with one or more aspects of the subject technology. 
         FIGS.  4 A,  4 B and  4 C  are diagrams illustrating example schemes with various locations for embedding optical sensors within a micro-LED display, in accordance with one or more aspects of the subject technology. 
         FIGS.  5 A and  5 B  are a table and a chart, respectively, illustrating examples of applications of optical-sensor-embedded micro-LED displays, in accordance with one or more aspects of the subject technology. 
         FIGS.  6 A,  6 B and  6 C  are charts illustrating optical characteristics of example material choices for optical sensors of an optical-sensor-embedded micro-LED display, in accordance with one or more aspects of the subject technology. 
         FIG.  7    is a schematic diagram illustrating an example readout circuit for an optical-sensor-embedded micro-LED display of the subject technology. 
         FIGS.  8 A,  8 B and  8 C  are schematic diagrams illustrating examples of collimation schemes for an optical-sensor-embedded micro-LED display, in accordance with one or more aspects of the subject technology. 
         FIG.  9    is a schematic diagram illustrating an example structure of a micro-LED display with embedded organic photodetectors (OPDs), in accordance with one or more aspects of the subject technology. 
         FIGS.  10 A and  10 B  are schematic diagrams illustrating examples of a process for creating a micro-LED display. 
         FIGS.  11 A and  11 B  are schematic diagrams illustrating examples of a process for integration of OPD with a micro-LED display, in accordance with one or more aspects of the subject technology. 
         FIGS.  12 A,  12 B,  12 C and  12 D  are schematic diagrams illustrating examples of different integration options for an optical sensor with a micro-LED display, in accordance with one or more aspects of the subject technology. 
         FIG.  13    is a schematic diagram illustrating an example of a wireless communication device in which the optical-sensor-embedded micro-LED display of the subject technology is utilized. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description set forth below is intended as a description of various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology may be practiced. The appended drawings are incorporated herein and constitute part of the detailed description. The detailed description includes specific details for the purpose of providing a thorough understanding of the subject technology. However, the subject technology is not limited to the specific details set forth herein and may be practiced without one or more of the specific details. In some instances, structures and components are shown in a block diagram form in order to avoid obscuring the concepts of the subject technology. 
     The subject technology is directed to a micro-light-emitting diode (LED) display with embedded optical sensors. In some aspects, the embedded optical sensors of the subject technology can be embedded on the micro-LED panel at the same plane with the red-green-blue (RGB) pixels. In other aspects of the subject technology, the embedded optical sensors can be integrated inside the micro-LED panel at the same plane with micro-drivers or underneath the micro-LED panel. 
     The optical-sensor-embedded micro-LED display of the subject technology can be used in a number of applications, such as ambient light sensing (ALS), fingerprint sensing, and proximity sensing. In some implementations, micro-LED chips under reverse bias or silicon-based p-i-n semiconductor (PIN) photodetectors can be used to realize the embedded optical sensors of the subject technology. In one or more implementations, the embedded optical sensors can be based on an organic photodetector (OPD), a dedicated silicon-based photodetector, a quantum-dot (QD) or quantum film (QF)-based optical sensor. 
     The spectral response wavelengths of the embedded optical sensors of the subject technology depends on the material used and can cover visible, near infra-red (IR) and short-wave IR (SWIR), especially when QD is used. The embedded optical sensors can be read out using different read-out circuits such as 3T-pixel, direct injection pixel or current trans-impedance amplifier (CTIA) read-out circuits. Embedded light collimators can be achieved by adding additional black matrix (BM) layers or using one or more QD focusing layers across the display, as discussed in more detail herein. 
       FIG.  1    is a schematic diagram illustrating a cross-sectional view of a section of an exemplary micro-LED display  100  with an embedded optical sensor, in accordance with one or more aspects of the subject technology. The cross-sectional view of the section of the micro-LED display  100  shown in  FIG.  1    includes an organic sensor  110 , a micro-LED  120 , a passivation layer  130  and a transparent conductive layer  140  and the wires  112  and  122 . The organic sensor  110  is integrated with the micro-LED  120  on a substrate and is isolated from the micro-LED  120  using the passivation layer  130 . The transparent conductive layer  140  can be an indium-tin oxide (ITO) layer that provides contact for the micro-LED  120  and the organic sensor  110 . The wires  112  and  122  are driver terminals of the organic sensor  110  and the micro-LED  120 , respectively, which can be realized by conductive traces. 
       FIG.  2    is a schematic diagram illustrating a shared driver circuit  202  of a micro-LED  220  and an embedded optical sensor  210  of a micro-LED display, in accordance with one or more aspects of the subject technology. An advantageous feature of the subject technology is that a single micro-driver, such as the shared driver circuit  202  (hereinafter, driver  202 ), can be used to drive the current of both the embedded optical sensor  210  and the micro-LED  220 . In some aspects, the driver  202  can be a passive or active matrix driver that can drive an array of micro-LEDs and optical sensors of a display. The embedded optical sensor  210  and the micro-LED  220  are coupled to the driver  202  via conductors  212  and  222 , which are the same as the wires  112  and  122  of  FIG.  1   . In some aspects, the micro-LED  220  (e.g., a red micro-LED) can be reverse biased and used as a photodetector. 
       FIGS.  3 A,  3 B and  3 C  are diagrams illustrating various example configurations  300 A,  300 B and  300 C for embedding optical sensors within a micro-LED display, in accordance with one or more aspects of the subject technology. The configuration  300 A of  FIG.  3 A  represents a portion  302  of a display  300 . In the configuration  300 A, one or more optical sensing elements  310  are located in an area surrounded by four RGB pixel blocks  304  ( 304 - 1 ,  304 - 2 ,  304 - 3  and  304 - 4 ) of the micro-LED display. Each RGB pixel block  304  includes a primary set and a redundant set of RGB pixels that are not in use. In some implementations, the dimensions d 1  and d 2  shown in  FIG.  3 A  are about 78 μm. 
     The configuration  300 B of  FIG.  3 B  represents a portion  302  of the display  300  of  FIG.  3 A . In the configuration  300 B, an array  310  of optical sensing elements is located in an area above the four RGB pixel blocks  304  ( 304 - 1 ,  304 - 2 ,  304 - 3  and  304 - 4 ) of the micro-LED display. Each RGB pixel block  302  includes a primary set and a redundant set of RGB pixels. In some implementations, the dimensions d 1  and d 2  shown in  FIG.  3 B  are about 78 μm. 
     The configuration  300 C of  FIG.  3 C  represents a portion  302  of the display  300  of  FIG.  3 A . In the configuration  300 C, the sensing elements  310  ( 310 - 1 ,  310 - 2 ,  310 - 3  and  310 - 4 ) are staggered in areas adjacent to the four RGB pixel blocks  304  ( 304 - 1 ,  304 - 2 ,  304 - 3  and  304 - 4 ) of the micro-LED display. Each RGB pixel block  304  includes a primary set and a redundant set of RGB pixels. 
       FIGS.  4 A,  4 B and  4 C  are diagrams illustrating example schemes  400 A,  400 B and  400 C with various locations for embedding optical sensors  410  within a micro-LED display  400 , in accordance with one or more aspects of the subject technology. The micro-LED display  400  includes a display panel  402 , a micro-LED panel  404  and a micro-driver layer  406 . The display panel  402  includes a cover glass attached to a polarizer layer through an optically clear adhesive (OCA) layer. The display panel  402  is coupled to the micro-LED panel  404  via a layer of OCA. The micro-LED panel  404  is disposed on the micro-driver layer  406  and includes an array of RGB pixel blocks similar to the RGB pixel blocks  304  of  FIG.  3   . 
     In the scheme  400 A of  FIG.  4 A , the optical sensors  410  are embedded in the micro-LED panel  404  at the same plane with the RGB pixels. The distribution of the optical sensors  410  within the micro-LED panel  404  can be based on configurations  300 A,  300 B and  300 C of  FIGS.  3 A,  3 B and  3 C , respectively, but is not limited to these configurations and can be based on other configurations. In the scheme  400 A, less electrical shielding and a desired optical transmission (e.g., 32%) can be achieved by avoiding metal traces and BM obstruction. In the scheme  400 A, an example value for the height of the optical sensors  410  is about 3.5 μm. 
     In the scheme  400 B of  FIG.  4 B , the optical sensors  410  are embedded in the micro-driver layer  406  underneath the plane of the RGB pixels. The distribution of the optical sensors  410  within the micro-driver layer  406  can be based on available free spaces in between the micro-drivers. The scheme  400 B may not provide the advantageous features of the scheme  400 A, with regard to the electrical shielding and optical transmission. In the scheme  400 A, an example value for the height of the optical sensors  410  can be about 8.5 μm. 
     In the scheme  400 C of  FIG.  4 C , the optical sensors  410  are embedded in a layer  408  underneath the micro-driver layer  406 . The scheme  400 C may provide the same or lower electrical and optical transmission compared to the scheme  400 B. Although the scheme  400 C results in increased height of the micro-LED display  400 , there is no limitation for the height of the optical sensors  410 . 
       FIGS.  5 A and  5 B  are a table  500 A and a chart  500 B, respectively, illustrating examples of applications of optical-sensor-embedded micro-LED displays, in accordance with one or more aspects of the subject technology. The table  500 A of  FIG.  5 A  includes an application column  502 , a goals column  504 , a wavelength column  506  and a column  508  specifying the potential additions to the display. The application column  502  shows various applications of the optical-sensor-embedded micro-LED display of the subject technology, including ambient light sensing, touch sensing, hover sensing, proximity sensing, fingerprint sensing, health sensing, and imaging. The achievable goals for each application are described in the corresponding row of that application. The wavelength column  506  specifies the corresponding wavelength of operation for each application. Finally, the column  508  shows the potential additions, such as photodetectors with various characteristics to the display device. 
     The chart  500 B of  FIG.  5 B  illustrates different applications of the optical-sensor-embedded micro-LED display of the subject technology in four regions of a two-dimensional space. The two dimensions are the chromaticity requirement for each application and the required sensing resolution for that application. The chart  500 B is self-explanatory. 
       FIGS.  6 A,  6 B and  6 C  are charts illustrating plots  600 A,  600 B and  600 C of optical characteristics of example material choices for optical sensors of an optical-sensor-embedded micro-LED display, in accordance with one or more aspects of the subject technology. The chart  600 A of  FIG.  6 A  is associated with a micro-LED option for realizing the embedded optical sensors (e.g.,  410  of  FIGS.  4 A,  4 B and  4 C ). The chart  600 A includes plots  602 ,  604  and  606 , which, respectively, show variations of quantum efficiency (QE) versus wavelength (in μm) for red, green and blue components of the light. The chart  600 A indicated that the micro-LED option achieves the highest QE for the green and blue components. The micro-LED can be used for fingerprint sensing and does not require additional pads to the micro-driver. 
     The chart  600 B of  FIG.  6 B  is associated with a Si photodiode (PD) option for realizing the embedded optical sensors (e.g.,  410  of  FIGS.  4 A,  4 B and  4 C ). The chart  600 B includes plots  612 ,  614  and  616 , which, respectively, show variations of QE versus wavelength (in μm) for red, green and blue components of the light. The chart  600 B also includes a plot  610 , which is a sum plot that adds QEs for the red, green and blue components of the light. The chart  600 B indicates that the Si PD option achieves the highest QE for the green and blue components. The Si PDs are easy to integrate with readout integrated circuits to achieve a monolithic solution. 
     The chart  600 C of  FIG.  6 C  is associated with an OPD option for realizing the embedded optical sensors (e.g.,  410  of  FIGS.  4 A,  4 B and  4 C ). The chart  600 C includes plots  620  and  622 , which, respectively, show variations of QE versus wavelength (in μm) for hole-injection layer (HIL) and electron-injection layer (EIL) options at about −2.5 V. The chart  600 C indicates that the OPD option achieves the highest QE for the EIL and can cover a longer wavelength range. The OPD can be implemented in the display panel, although it may be susceptible to degradation if exposed to excessive light and moisture. 
     In some aspects, a QD or QF photodiode can be used as the optical sensor. These photodiodes are tunable in visible, NIR and SWIR wavelength regions. The issue with these photodiodes, however, is reliability and degradation with exposure to excessive light and moisture and process integration. 
       FIG.  7    is a schematic diagram illustrating an example readout circuit  700  for an optical-sensor-embedded micro-LED display of the subject technology. The readout circuit  700  includes a capacitive transimpedance amplifier (CTIA)  702 , a switch  704 , a capacitor C and a floating diffusion (FD) storage  706 . The FD storage  706 , which is used as the sense node for the charge signal, is connected to a cathode terminal of an optical sensor  710  to be readout. The optical sensor  710  is the embedded optical sensor of the subject technology. The CTIA  702  is biased via a voltage source VSS and provides an output voltage signal Vout in response to the current signal of the FD storage  706 , which is in turn responsive to the signal from the optical sensor  710 . 
       FIGS.  8 A,  8 B and  8 C  are schematic diagrams illustrating examples of collimation schemes  800 A,  800 B and  800 C for an optical-sensor-embedded micro-LED display, in accordance with one or more aspects of the subject technology. In the collimation scheme  800 A, a micro-LED display  800  is shown that is used for fingerprint sensing, and micro-LEDs are utilized both for pixels and for optical sensing. The micro-LED display  800  includes a cover glass  802 , a polarizer layer  804 , microlenses  806 , a diffuser layer  808 , BM layers  820  ( 820 - 1  and  820 - 2 ) and micro-LEDs  810  ( 810 - 1 ,  810 - 2 ,  810 - 3  and  810 - 4 ). The BM layer  820 - 1  is the lower layer in the micro-LED plane and the BM layer  820 - 2  is formed under the polarizer layer  804 . The function of the BM layers  820  is to collimate the scattered light ray (e.g.,  830 - 1  and  830 - 2 ) from different regions of the finger and focus onto the pixel micro-LEDs  810 - 1  and  810 - 4 , respectively, and then prevent them from reaching the optical sensors  810 - 2  and  810 - 3 . The BM layer collimators can be used for proximity sensor applications as well. 
     In the collimation scheme  800 B of  FIG.  8 B , the collimation is provided by a pinhole mask  832 , which is created on top of the photodiodes  830 , and is covered by a transparent spacer  840  and a microlens  850 . The microlens  850  can focus the incident light rays  840 - 1  onto the pinhole of the pinhole mask  832  and have the incident light rays  840 - 2  and  840 - 3  blocked from reaching the pinhole as shown in  FIG.  8 B . 
     The collimation scheme  800 C of  FIG.  8 C  is similar to the collimation scheme  800 B, except that the microlens  850  is replaced with a second pinhole mask  832 - 2 , which can be realized by using a second metal layer and is disposed on top of the transparent spacer  840 . The first pinhole mask  832 - 1  can be realized by a first metal layer and is disposed on the photodiodes  830  and together with the second pinhole mask  832 - 2  form the collimator. 
       FIG.  9    is a schematic diagram illustrating an example structure of a micro-LED display  900  with embedded OPDs, in accordance with one or more aspects of the subject technology. The micro-LED display  900  is a thin-film transistor (TFT) based display and includes a TFT layer  902 , a data connector layer  904 , a bias connector layer  906 , pixels  908 , a passive layer  910 , an active layer  912 , a top electrode (HIL electrode)  914  and a protective layer  916 . All the dimension values shown in  FIG.  9    are exemplary values and may change depending on the process and design. In the micro-LED display  900 , the active layer is the light sensing layer, which can be an OPD layer, and is integrated within the micro-LED panel. 
       FIGS.  10 A and  10 B  are schematic diagrams illustrating examples of a process  1000 A for creating a micro-LED display  1000 . The micro-LED display  1000  includes an anisotropic conductive film (ACF)  1020 , RGB pixels  1022 , a passive layer  1024 , an ITO layer  1026 , a diffuser layer  1028  and a BM layer  1030 . The process  1000 A includes steps for creating the micro-LED display  1000  without optical sensors. The process  1000 A begins with operational step  1002 , which is a BM4 ITO process for creating the ACF layer  1020  and the RGB pixels  1022 . In the next process step  1004 , the passive layer  1024  is created using a suitable deposition (coating) technique followed by lithography. In process step  1006 , the ITO layer  1026  is formed by using a deposition and lithography. In process step  1008 , deposition and lithography techniques are used to provide the diffuser layer  1028 . Finally at process step  1010 , the BM layer  1030  is formed by using a suitable deposition and lithography process. 
       FIGS.  11 A and  11 B  are schematic diagrams illustrating examples of a process  1100 A for integration of OPD with a micro-LED display, in accordance with one or more aspects of the subject technology. The process  1100 A is the continuation of the process  1000 A to prepare an OPD-sensor-embedded micro-LED display  1100 , which includes the micro-LED display  1000  of  FIG.  10 B  integrated with an OPD sensor module  1110 . The OPD sensor module  1110  includes an OPD sensor  1112  and corresponding EIL and HIL layers. The process  1000 A includes process steps  1102 ,  1104 ,  1106  and  1108 . In process step  1102 , the substrate is prepared for formation of the EIL, OPD sensor  1112  and the HIL. In process step  1104 , using a suitable deposition technique and lithography, the EIL layer and the OPD sensor  1112  are created. Next, at process step  1106 , the HIL layer is coated and patterned. Finally, in process step  1108 , the OPD-sensor-embedded micro-LED display  1100  is encapsulated using a passivation layer  1120 . 
       FIGS.  12 A,  12 B,  12 C and  12 D  are schematic diagrams illustrating examples of different integration options  1200 A,  1200 B,  1200 C and  1200 D for an optical sensor with a micro-LED display, in accordance with one or more aspects of the subject technology. In the integration option  1200 A shown in  FIG.  12 A  the starting die includes the RGB pixels  1204  and the OPD  1210 . In this option the OPD cathode is the BM4 ITO  1202 . In the integration option  1200 B shown in  FIG.  12 B  the starting die includes the RGB pixels  1204  and the passivation layer  1212 , and the OPD  1210  is deposited after coating the passivation layer  1212 . In this option the OPD cathode is the BM4 ITO  1202 . In the integration option  1200 C shown in  FIG.  12 C  the starting die includes the RGB pixels  1204 , the passivation layer  1212  and the ITO layer  1214 , and the OPD  1210  is deposited after coating the ITO layer  1214 . In this option the OPD cathode is the ITO layer  1214 . In the integration option  1200 D shown in  FIG.  12 D  the starting die includes the RGB pixels  1204 , the passivation layer  1212 , the ITO layer  1214  and the diffuser layer  1216 , and the OPD  1210  is deposited after coating the diffuser layer  1216 . In this option the OPD cathode is the ITO layer  1214 . Each of these options has their corresponding advantages and disadvantages. Examples of advantages of these options includes the integration option  1200 A requires fewer mask layers; the integration option  1200 B requires fewer mask layers and the uniformity of the passivation layer  1212  is minimally affected; the integration option  1200 C has minimal impact on the display layers and minimal change to the OPD process; and, similarly, the integration option  1200 D has minimal impact on the display layers and minimal change to the OPD process. 
       FIG.  13    is a schematic diagram illustrating an example of a wireless communication device  1300  in which the optical-sensor-embedded micro-LED display of the subject technology is utilized. In one or more implementations, the wireless communication device  1300  can be a smartphone or a smartwatch. The wireless communication device  1300  may comprise a radio-frequency (RF) antenna  1310 , a duplexer  1312 , a receiver  1320 , a transmitter  1330 , a baseband processing module  1340 , a memory  1350 , a processor  1360 , a local oscillator generator (LOGEN)  1370  and a display  1380 . In various embodiments of the subject technology, one or more of the blocks represented in  FIG.  13    may be integrated on one or more semiconductor substrates. For example, the blocks  1320 - 1370  may be realized in a single chip or a single system on a chip, or may be realized in a multichip chipset. 
     The receiver  1320  may comprise suitable logic circuitry and/or code that may be operable to receive and process signals from the RF antenna  1310 . The receiver  1320  may, for example, be operable to amplify and/or down-convert received wireless signals. In various embodiments of the subject technology, the receiver  1320  may be operable to cancel noise in received signals and may be linear over a wide range of frequencies. In this manner, the receiver  1320  may be suitable for receiving signals in accordance with a variety of wireless standards, Wi-Fi, WiMAX, Bluetooth, and various cellular standards. In various embodiments of the subject technology, the receiver  1320  may not require any SAW filters and few or no off-chip discrete components such as large capacitors and inductors. 
     The transmitter  1330  may comprise suitable logic circuitry and/or code that may be operable to process and transmit signals from the RF antenna  1310 . The transmitter  1330  may, for example, be operable to up-convert baseband signals to RF signals and amplify RF signals. In various embodiments of the subject technology, the transmitter  1330  may be operable to up-convert and amplify baseband signals processed in accordance with a variety of wireless standards. Examples of such standards may include Wi-Fi, WiMAX, Bluetooth, and various cellular standards. In various embodiments of the subject technology, the transmitter  1330  may be operable to provide signals for further amplification by one or more power amplifiers. 
     The duplexer  1312  may provide isolation in the transmit band to avoid saturation of the receiver  1320  or damaging parts of the receiver  1320 , and to relax one or more design requirements of the receiver  1320 . Furthermore, the duplexer  1312  may attenuate the noise in the receive band. The duplexer may be operable in multiple frequency bands of various wireless standards. 
     The baseband processing module  1340  may comprise suitable logic, circuitry, interfaces, and/or code that may be operable to perform processing of baseband signals. The baseband processing module  1340  may, for example, analyze received signals and generate control and/or feedback signals for configuring various components of the wireless communication device  1300 , such as the receiver  1320 . The baseband processing module  1340  may be operable to encode, decode, transcode, modulate, demodulate, encrypt, decrypt, scramble, descramble, and/or otherwise process data in accordance with one or more wireless standards. 
     The processor  1360  may comprise suitable logic, circuitry, and/or code that may enable processing data and/or controlling operations of the wireless communication device  1300 . In this regard, the processor  1360  may be enabled to provide control signals to various other portions of the wireless communication device  1300 . The processor  1360  may also control transfers of data between various portions of the wireless communication device  1300 . Additionally, the processor  1360  may enable implementation of an operating system or otherwise execute code to manage operations of the wireless communication device  1300 . 
     The memory  1350  may comprise suitable logic, circuitry, and/or code that may enable storage of various types of information such as received data, generated data, code, and/or configuration information. The memory  1350  may comprise, for example, RAM, ROM, flash, and/or magnetic storage. In various embodiments of the subject technology, information stored in the memory  1350  may be utilized for configuring the receiver  1320  and/or the baseband processing module  1340 . 
     The LOGEN  1370  may comprise suitable logic, circuitry, interfaces, and/or code that may be operable to generate one or more oscillating signals of one or more frequencies. The LOGEN  1370  may be operable to generate digital and/or analog signals. In this manner, the LOGEN  1370  may be operable to generate one or more clock signals and/or sinusoidal signals. Characteristics of the oscillating signals, such as the frequency and duty cycle, may be determined based on one or more control signals from, for example, the processor  1360  and/or the baseband processing module  1340 . 
     In operation, the processor  1360  may configure the various components of the wireless communication device  1300  based on a wireless standard according to which it is desired to receive signals. Wireless signals may be received via the RF antenna  1310 , amplified, and down-converted by the receiver  1320 . The baseband processing module  1340  may perform noise estimation and/or noise cancellation, decoding, and/or demodulation of the baseband signals. In this manner, information in the received signal may be recovered and utilized appropriately. For example, the information may be audio and/or video to be presented to a user of the wireless communication device, data to be stored to the memory  1350 , and/or information affecting and/or enabling operation of the wireless communication device  1300 . The baseband processing module  1340  may modulate, encode, and perform other processing on audio, video, and/or control signals to be transmitted by the transmitter  1330  in accordance with various wireless standards. 
     The display  1380  may be the optical-sensor-embedded micro-LED display of the subject technology as described above. The use of the optical-sensor-embedded micro-LED display of the subject technology is not limited to wireless communication devices, and the disclosed display technology can be used in any electronic device having a display such as a laptop computer or other electronic devices. 
     In one or more implementations, the processor  1360  can process sensor signals from the optical sensors integrated with the micro-LED display of the subject technology, after being converted to digital signals by an analog-to-digital converter (ADC) (e.g., an ADC of the communication device  1300 ). 
     The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” Unless specifically stated otherwise, the term “some” refers to one or more. Pronouns in the masculine (e.g., his) include the feminine and neutral gender (e.g., her and its) and vice versa. Headings and subheadings, if any, are used for convenience only and do not limit the subject disclosure. 
     The predicate words “configured to,” “operable to,” and “programmed to” do not imply any particular tangible or intangible modification of a subject, but, rather, are intended to be used interchangeably. For example, a processor configured to monitor and control an operation or a component may also mean the processor being programmed to monitor and control the operation or the processor being operable to monitor and control the operation. Likewise, a processor configured to execute code can be construed as a processor programmed to execute code or operable to execute code. 
     A phrase such as “an aspect” does not imply that such aspect is essential to the subject technology or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect may apply to all configurations, or one or more configurations. A phrase such as “an aspect” may refer to one or more aspects and vice versa. A phrase such as “a configuration” does not imply that such configuration is essential to the subject technology or that such configuration applies to all configurations of the subject technology. A disclosure relating to a configuration may apply to all configurations, or one or more configurations. A phrase such as “a configuration” may refer to one or more configurations and vice versa. 
     The word “example” is used herein to mean “serving as an example or illustration.” Any aspect or design described herein as “example” is not necessarily to be construed as preferred or advantageous over other aspects or designs. 
     All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. § 112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.” Furthermore, to the extent that the term “include,” “have,” or the like is used in the description or the claims, such term is intended to be inclusive in a manner similar to the term “comprise” as “comprise” is interpreted when employed as a transitional word in a claim.

Metadata:
Filing Date: 20210810
Publication Date: 20241217
Grant Date: 20241217
Priority Date: 20200902
Inventors: NIU, XIAOFAN
KANG, SUNGGU
YEKE YAZDANDOOST, MOHAMMAD
GOZZINI, GIOVANNI
LI, XIA
CELLEK, Oray O.
CHALASANI, Sandeep
MOLESA, STEVEN E.
CHOI, JAEIN
Assignee: APPLE INC
CPC Classifications: [{"code": "H10F39/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2300/0452", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/32", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K39/30", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2300/0426", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/32", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01L25/0753", "inventive": false, "first": false, "tree": "[]"}, {"code": "H10K39/30", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L25/167", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01L25/167", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09F9/33", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G2360/144", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2300/0452", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/32", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01L25/167", "inventive": true, "first": true, "tree": "[]"}]
Family ID: 80357352