Patents by Inventor John T. Wetherell

John T. Wetherell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20250095605
    Abstract: Electronic displays may display a frame of image content by controlling emissions of display pixels. To this end, the electronic display may include one or more column drivers that drive the display pixels to emit light. The column drivers may be collectively compensated by common components, such as a single sampling capacitor and/or an analog buffer, which may reduce a size of the column drivers. In another example, the column drivers may include cascode transistors with increased width-to-length ratio and share a common n-well. Each transistor may be compensated by a respective capacitor, however a size of each sampling capacitor may be reduced, thereby reducing a size of the column driver. Moreover, a size of a level shifter may be reduced by operating transistors of the level shifter with sub-threshold voltage. Furthermore, a resolution of the electronic display may be improved by extending a pulse of an emission clock signal.
    Type: Application
    Filed: April 2, 2024
    Publication date: March 20, 2025
    Inventors: Baris Posat, John T. Wetherell, Hasan Akyol, Mahdi Farrokh Baroughi, Hopil Bae
  • Publication number: 20250095548
    Abstract: Electronic displays may display a frame of image content by controlling emissions of display pixels. To this end, the electronic display may include one or more column drivers that drive the display pixels to emit light. The column drivers may be collectively compensated by common components, such as a single sampling capacitor and/or an analog buffer, which may reduce a size of the column drivers. In another example, the column drivers may include cascode transistors with increased width-to-length ratio and share a common n-well. Each transistor may be compensated by a respective capacitor, however a size of each sampling capacitor may be reduced, thereby reducing a size of the column driver. Moreover, a size of a level shifter may be reduced by operating transistors of the level shifter with sub-threshold voltage. Furthermore, a resolution of the electronic display may be improved by extending a pulse of an emission clock signal.
    Type: Application
    Filed: April 2, 2024
    Publication date: March 20, 2025
    Inventors: Baris Posat, John T Wetherell, Hasan Akyol, Mahdi Farrokh Baroughi
  • Publication number: 20240420615
    Abstract: An electronic device may include a display panel and a display driver. The display panel may include multiple pixels each receiving a supply voltage and a respective data voltage to emit light. The display driver may include a low drop-out regulator (LDO) to provide the supply voltage to the pixels. The LDO may operate in a normal operation mode and a hard park mode. In the normal operation mode, the LDO may generate the supply voltage based on receiving a reference voltage and a bias voltage within a bias voltage range to operate in the normal operation mode. In the hard park mode, the LDO may become idle (e.g., shut-down mode) based on receiving a hard park mode voltages from dedicated replacement circuits. For example, including the dedicated reference voltage replacement circuit with the display driver may improve reliability and efficiency of the electronic device when de-energizing the LDO.
    Type: Application
    Filed: May 9, 2024
    Publication date: December 19, 2024
    Inventors: Hasan Akyol, Henry C. Jen, Stanley B. Wang, Baris Cagdaser, Rahul Shukla, John T. Wetherell, Bin Huang, Derek K. Shaeffer, Pablo Moreno Galbis, Johan L. Piper, Lawrence C. Tan, Adam Adjiwibawa, Manu Mishra
  • Publication number: 20240402237
    Abstract: Systems and methods are provided for electrical testing to supplement or replace optical testing of an electronic display. Internal testing circuitry that includes analog front end (AFE) and analog-to-digital converter (ADC) circuitry may be included in the electronic display and may be used either alone or in combination with other testing devices to perform electrical characterization and defect screening. The electrical characterization and defect screening may be performed before or after self-emissive elements such as light-emitting diodes are installed, further improving yield. Types of electrical characterization and defect screening may include a partial passive mode electrical characterization of OLEDs, vertical or horizontal crosstalk measurement, scan line integrity testing, pixel bright dot testing, display pixel defect detection, and delayed defect detection for defects that may occur after some extended period of time (e.g., after several minutes, after several hours).
    Type: Application
    Filed: May 6, 2024
    Publication date: December 5, 2024
    Inventors: Xuebei Yang, Chung-Lun E Hsu, Cheuk Chi Lo, Hasan Akyol, Yingkan Lin, John T Wetherell, Han Zhao
  • Patent number: 12159574
    Abstract: Local passive matrix displays and methods of operation are described. In an embodiment, the display includes a pixel driver chip coupled with a matrix of rows and columns of LEDs. The pixel driver chips may be arranged in rows across the display with separate portions to operate separate matrices of LEDs.
    Type: Grant
    Filed: April 4, 2023
    Date of Patent: December 3, 2024
    Assignee: Apple Inc.
    Inventors: Derek K. Shaeffer, Mahdi Farrokh Baroughi, Xiaofeng Wang, Sam S. Li, John T. Wetherell, Henry C. Jen, Xiang Lu, Hasan Akyol, Hopil Bae, Xiang Fang, Hjalmar Edzer Ayco Huitema, Tore Nauta
  • Patent number: 12080201
    Abstract: An integrated touchscreen can include light emitting diodes or organic light emitting diodes (LEDs/OLEDs), display chiplets and touch chiplets disposed in a visible area of the integrated touch screen. For example, the LEDs/OLEDs, display chiplets and touch chiplets can be placed on a substrate by a micro-transfer tool. The integrated touchscreen can also include electrodes disposed in the visible area of the integrated touch screen. The electrodes can be capable of providing display functionality via the one or more display chiplets during display operation (e.g., operating as cathode terminals of the LEDs during the display operation) and capable of providing touch functionality via the touch chiplets during touch operation (e.g., touch node electrodes can be formed from groups of the electrodes and sensed). In some examples, the touch node electrodes can be formed and coupled to touch chiplets via the display chiplets.
    Type: Grant
    Filed: September 15, 2023
    Date of Patent: September 3, 2024
    Assignee: Apple Inc.
    Inventors: Christian M. Sauer, Christoph H. Krah, Derek K. Shaeffer, Hasan Akyol, Henry C. Jen, John T. Wetherell
  • Patent number: 12027117
    Abstract: Systems and methods may reduce or eliminate image artifacts due to a defective pixel of an electronic display. An electronic display may include pixels that respectively include a self-emissive element, pixel drive circuitry that supplies a pixel drive current to drive the self-emissive element, and signal routing circuitry that reduces or eliminates a visual artifact due to a defective pixel among the pixels. The signal routing circuitry may do this by turning off the self-emissive element, supplying image data from the pixel drive circuitry to a first adjacent pixel, or receiving image data from other pixel drive circuitry from the first adjacent pixel or a second adjacent pixel.
    Type: Grant
    Filed: September 10, 2021
    Date of Patent: July 2, 2024
    Assignee: Apple Inc.
    Inventors: John T. Wetherell, Cheuk Chi Lo, Chun-Yao Huang, Lingtao Wang, Derek Keith Shaeffer, Henry C. Jen, Hasan Akyol, Xuebei Yang, Chung-Lun Edwin Hsu, Patrick Bryce Bennett, Chun-Ming Tang, Yingkan Lin, Sheng Zhang, Chaohao Wang, Runjie Xu, Shingo Hatanaka
  • Publication number: 20240105525
    Abstract: Test structures and methods of testing pixel driver chip donor wafers are described. In an embodiment, a redistribution layer is formed over a pixel driver chip donor wafer and probed to determine known good dies, followed by removal of the RDL. In other embodiments, test routing is formed in the pixel driver chip using a polycide material or doped region in the semiconductor wafer.
    Type: Application
    Filed: July 25, 2023
    Publication date: March 28, 2024
    Inventors: Imran Hashim, Xiang Lu, Stanley B. Wang, Xuchun Liu, Mahdi Farrokh Baroughi, Yongjie Jiang, Hopil Bae, Hasan Akyol, Baris Posat, John T. Wetherell, Lei Wu
  • Publication number: 20240004491
    Abstract: An integrated touchscreen can include light emitting diodes or organic light emitting diodes (LED s/OLEDs), display chiplets and touch chiplets disposed in a visible area of the integrated touch screen. For example, the LEDs/OLEDs, display chiplets and touch chiplets can be placed on a substrate by a micro-transfer tool. The integrated touchscreen can also include electrodes disposed in the visible area of the integrated touch screen. The electrodes can be capable of providing display functionality via the one or more display chiplets during display operation (e.g., operating as cathode terminals of the LEDs during the display operation) and capable of providing touch functionality via the touch chiplets during touch operation (e.g., touch node electrodes can be formed from groups of the electrodes and sensed). In some examples, the touch node electrodes can be formed and coupled to touch chiplets via the display chiplets.
    Type: Application
    Filed: September 15, 2023
    Publication date: January 4, 2024
    Inventors: Christian M. SAUER, Christoph H. KRAH, Derek K. SHAEFFER, Hasan AKYOL, Henry C. JEN, John T. WETHERELL
  • Publication number: 20240005848
    Abstract: An electronic device may include an electronic display including display pixels to display an image based on compensated image data. As image data is written to a pixel in the row of pixels, capacitive coupling at a driver may lead to distortion on the driver. In particular, the capacitive coupling may cause distortion at a storage capacitor, which may lead to current droop at the pixel. The current droop may be reduced or eliminated in each pixel by performing pixel compensation. The pattern of the pixel compensation may be selected such that, over a number of subframes, an average amount of light is the same or similar to what would be emitted had pixel compensation been performed on each pixel in each subframe.
    Type: Application
    Filed: June 14, 2023
    Publication date: January 4, 2024
    Inventors: Jeongsup Lee, Hasan Akyol, Xiang Lu, Mahdi Farrokh Baroughi, Nikhil Acharya, Haitao Li, Hopil Bae, John T Wetherell, Shengzhe Jiao, Stanley B. Wang, Sunmin Jang, Hari P. Paudel, Eric A. Hildebrandt, Young Don Bae
  • Patent number: 11783739
    Abstract: Embodiments disclosed herein provide systems and methods for testing and repairing various aspects of an electronic display. The electronic display includes a reference array and an active array. The electronic display also includes test circuitry used to test individual or any combination of pixels of the electronic display. Switches may be disposed between the pixels and the test circuitry to be to repair the various components of the electronic display.
    Type: Grant
    Filed: August 9, 2021
    Date of Patent: October 10, 2023
    Assignee: Apple Inc.
    Inventors: Hasan Akyol, Xuebei Yang, Chung-Lun Edwin Hsu, Henry C. Jen, John T. Wetherell
  • Publication number: 20230316998
    Abstract: Local passive matrix displays and methods of operation are described. In an embodiment, the display includes a pixel driver chip coupled with a matrix of rows and columns of LEDs. The pixel driver chips may be arranged in rows across the display with separate portions to operate separate matrices of LEDs.
    Type: Application
    Filed: April 4, 2023
    Publication date: October 5, 2023
    Inventors: Derek K. Shaeffer, Mahdi Farrokh Baroughi, Xiaofeng Wang, Sam S. Li, John T. Wetherell, Henry C. Jen, Xiang Lu, Hasan Akyol, Hopil Bae, Xiang Fang, Hjalmar Edzer Ayco Huitema, Tore Nauta
  • Patent number: 11775095
    Abstract: An integrated touchscreen can include light emitting diodes or organic light emitting diodes (LEDs/OLEDs), display chiplets and touch chiplets disposed in a visible area of the integrated touch screen. For example, the LEDs/OLEDs, display chiplets and touch chiplets can be placed on a substrate by a micro-transfer tool. The integrated touchscreen can also include electrodes disposed in the visible area of the integrated touch screen. The electrodes can be capable of providing display functionality via the one or more display chiplets during display operation (e.g., operating as cathode terminals of the LEDs during the display operation) and capable of providing touch functionality via the touch chiplets during touch operation (e.g., touch node electrodes can be formed from groups of the electrodes and sensed). In some examples, the touch node electrodes can be formed and coupled to touch chiplets via the display chiplets.
    Type: Grant
    Filed: July 23, 2021
    Date of Patent: October 3, 2023
    Assignee: Apple Inc.
    Inventors: Christian M. Sauer, Christoph H. Krah, Derek K. Shaeffer, Hasan Akyol, Henry C. Jen, John T. Wetherell, Thierry S. Divel
  • Patent number: 11705037
    Abstract: In an embodiment, an electronic display includes an active area including a plurality of pixels arranged in columns and a plurality of source drivers driving image data to columns of pixels. The electronic display also includes a first plurality of switches selectively coupling respective source drivers of the plurality of source drivers to one or more columns. Selective coupling enables the respective source drivers to, at different times, drive the image data to: a single column; and multiple columns. In another embodiment, an electronic display includes a display panel configured to operate using a reference voltage received via a resistive path having a routing resistance, a reference voltage source outputting the reference voltage, and a feedback circuit sensing an electrical parameter of the resistive path and producing a compensation voltage that, when added to the reference voltage, causes the reference voltage to remain substantially constant at the display panel.
    Type: Grant
    Filed: August 20, 2021
    Date of Patent: July 18, 2023
    Assignee: Apple Inc.
    Inventors: Omar Hafiz, Baris Cagdaser, John T. Wetherell, Han Zhao
  • Patent number: 11657742
    Abstract: Embodiments disclosed herein provide systems and methods for testing and repairing various aspects of an electronic display. The electronic display includes a reference array and an active array. The electronic display also includes test circuitry used to test individual or any combination of pixels of the electronic display. Switches may be disposed between the pixels and the test circuitry to be to repair the various components of the electronic display.
    Type: Grant
    Filed: August 11, 2021
    Date of Patent: May 23, 2023
    Assignee: Apple Inc.
    Inventors: Hasan Akyol, Chung-Lun Edwin Hsu, Baris Cagdaser, John T. Wetherell, Xuebei Yang, Ali Tabatabaei, Patrick Bryce Bennett, Yingkan Lin, Chun-Ming Tang, Xiaofeng Wang, Hopil Bae
  • Patent number: 11651719
    Abstract: An electronic device may include an electronic display panel having multiple display pixels for displaying an image based on analog voltage signals. The electronic device may also include interpolation circuitry to generate the analog voltage signals based on digital image data corresponding to the image. The interpolation circuitry may also receive analog reference voltages and interpolate between sets of the analog reference voltages to generate intermediate voltages, which may be a part of the analog voltage signals. Interpolating between the sets analog reference voltages may include performing a first level interpolation of a first set of the analog reference voltages to generate a first intermediate voltage and performing a second level interpolation of a second set of the analog reference voltages to generate a second intermediate voltage, wherein the first level interpolation is different from the second level interpolation.
    Type: Grant
    Filed: July 14, 2021
    Date of Patent: May 16, 2023
    Assignee: Apple Inc.
    Inventors: John T. Wetherell, Mahdi Farrokh Baroughi, Jaeyoung Kang, Shingo Hatanaka, Hasan Akyol, Hopil Bae
  • Patent number: 11645957
    Abstract: Embodiments disclosed herein provide systems and methods for testing and repairing various aspects of an electronic display. The electronic display includes a reference array and an active array. The electronic display also includes test circuitry used to test individual or any combination of pixels of the electronic display. Switches may be disposed between the pixels and the test circuitry to be to repair the various components of the electronic display.
    Type: Grant
    Filed: August 11, 2021
    Date of Patent: May 9, 2023
    Assignee: Apple Inc.
    Inventors: John T. Wetherell, Hasan Akyol, Xuebei Yang, Xiaofeng Wang, Hopil Bae
  • Patent number: 11645976
    Abstract: Local passive matrix displays and methods of operation are described. In an embodiment, the display includes a pixel driver chip coupled with a matrix of rows and columns of LEDs. The pixel driver chips may be arranged in rows across the display with separate portions to operate separate matrices of LEDs.
    Type: Grant
    Filed: January 14, 2022
    Date of Patent: May 9, 2023
    Assignee: Apple Inc.
    Inventors: Derek K. Shaeffer, Mahdi Farrokh Baroughi, Xiaofeng Wang, Sam S. Li, John T. Wetherell, Henry C. Jen, Xiang Lu, Hasan Akyol, Hopil Bae, Xiang Fang, Hjalmar Edzer Ayco Huitema, Tore Nauta
  • Publication number: 20220208091
    Abstract: Local passive matrix displays and methods of operation are described. In an embodiment, the display includes a pixel driver chip coupled with a matrix of rows and columns of LEDs. The pixel driver chips may be arranged in rows across the display with separate portions to operate separate matrices of LEDs.
    Type: Application
    Filed: January 14, 2022
    Publication date: June 30, 2022
    Inventors: Derek K. Shaeffer, Mahdi Farrokh Baroughi, Xiaofeng Wang, Sam S. Li, John T. Wetherell, Henry C. Jen, Xiang Lu, Hasan Akyol, Hopil Bae, Xiang Fang, Hjalmar Edzer Ayco Huitema, Tore Nauta
  • Publication number: 20220101772
    Abstract: An electronic device may include an electronic display panel having multiple display pixels for displaying an image based on analog voltage signals. The electronic device may also include interpolation circuitry to generate the analog voltage signals based on digital image data corresponding to the image. The interpolation circuitry may also receive analog reference voltages and interpolate between sets of the analog reference voltages to generate intermediate voltages, which may be a part of the analog voltage signals. Interpolating between the sets analog reference voltages may include performing a first level interpolation of a first set of the analog reference voltages to generate a first intermediate voltage and performing a second level interpolation of a second set of the analog reference voltages to generate a second intermediate voltage, wherein the first level interpolation is different from the second level interpolation.
    Type: Application
    Filed: July 14, 2021
    Publication date: March 31, 2022
    Inventors: John T. Wetherell, Mahdi Farrokh Baroughi, Jaeyoung Kang, Shingo Hatanaka, Hasan Akyol, Hopil Bae