Patents by Inventor Tae-Wook Koh

Tae-Wook Koh 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).

  • Patent number: 12154487
    Abstract: Image processing circuitry may include burn-in compensation circuitry that receives image data indicative of luminance outputs for display pixels of an electronic display and compensates the image data for burn-in related aging associated with the display pixels, generating compensated image data. Moreover, compensating the image data may include applying gains based on estimated amounts of aging associated with the display pixels and estimated amounts of current to be delivered to the display pixels. The image processing circuitry may also include burn-in statistics circuitry that tracks the estimated amounts of aging based on the compensated image data.
    Type: Grant
    Filed: March 8, 2023
    Date of Patent: November 26, 2024
    Assignee: Apple Inc.
    Inventors: Vincent Z Young, Mahesh B Chappalli, Tae-Wook Koh, Yifan Zhang, Jared S Price
  • Patent number: 12142219
    Abstract: An electronic device may include an electronic display having a pixel and that displays an image based on compensated image data. The electronic device may also include image processing circuitry communicatively coupled to the electronic display. The image processing circuitry may receive image data and determine a gain value for the pixel based on an aging value of the pixel that is based on previously displayed pixel values of the pixel. The image processing circuitry may also adjust the gain value based on a pixel value of the image data corresponding to the pixel to generate an updated gain value and adjust the pixel value of the image data based on the updated gain value to generate, at least in part, the compensated image data.
    Type: Grant
    Filed: September 12, 2023
    Date of Patent: November 12, 2024
    Assignee: Apple Inc.
    Inventors: Tae-Wook Koh, Mahesh B Chappalli, Jared S Price, Vincent Z Young, Yifan Zhang
  • Patent number: 12125436
    Abstract: An electronic device may include an electronic display having display pixels that display an image based on compensated image data. The electronic display may also include pixel drive circuitry that provides power to the display pixels in accordance with the compensated image data. Additionally, the electronic device may include burn-in compensation circuitry communicatively coupled to the electronic display that receives input image data and generates the compensated input image data based on the input image data, a pixel aging history corresponding to the display pixels, and a driver aging history corresponding to the pixel drive circuitry.
    Type: Grant
    Filed: May 30, 2023
    Date of Patent: October 22, 2024
    Assignee: Apple Inc.
    Inventors: Tae-Wook Koh, Mahesh B Chappalli, Vincent Z Young, Yifan Zhang, Jared S Price
  • Publication number: 20240304133
    Abstract: Image processing circuitry may include burn-in compensation circuitry that receives image data indicative of luminance outputs for display pixels of an electronic display and compensates the image data for burn-in related aging associated with the display pixels, generating compensated image data. Moreover, compensating the image data may include applying gains based on estimated amounts of aging associated with the display pixels and estimated amounts of current to be delivered to the display pixels. The image processing circuitry may also include burn-in statistics circuitry that tracks the estimated amounts of aging based on the compensated image data.
    Type: Application
    Filed: March 8, 2023
    Publication date: September 12, 2024
    Inventors: Vincent Z Young, Mahesh B Chappalli, Tae-Wook Koh, Yifan Zhang, Jared S Price
  • Patent number: 12027105
    Abstract: Image processing circuitry may include burn-in compensation circuitry that receives image data indicative of luminance outputs for display pixels of an electronic display and compensates the image data for burn-in related aging associated with the display pixels, generating compensated image data. Moreover, compensating the image data may include applying gains based on estimated amounts of aging associated with the display pixels and estimated amounts of current to be delivered to the display pixels. The image processing circuitry may also include burn-in statistics circuitry that tracks the estimated amounts of aging based on the compensated image data.
    Type: Grant
    Filed: March 8, 2023
    Date of Patent: July 2, 2024
    Assignee: Apple Inc.
    Inventors: Vincent Z Young, Mahesh B Chappalli, Tae-Wook Koh, Yifan Zhang, Jared S Price
  • Patent number: 11688363
    Abstract: An electronic device may include an electronic display including display pixels to display an image based on compensated image data. The electronic display may also include a stressed reference pixel to exhibit burn-in related aging in response to one or more stress sessions and a non-stressed reference pixel configured to not undergo the one or more stress sessions. Additionally, the electronic device may include image processing circuitry to determine a panel-specific aging profile based on a comparison between one or more properties of the stressed reference pixel and the one or more properties of the non-stressed reference pixel. The image processing circuitry may also generate one or more gain maps based on the panel-specific aging profile and generate the compensated image data by applying the one or more gain maps to input image data.
    Type: Grant
    Filed: July 14, 2021
    Date of Patent: June 27, 2023
    Assignee: Apple Inc.
    Inventors: Maofeng Yang, Jiayi Jin, David A. Doyle, Yifan Zhang, Weijun Yao, Jiye Lee, Tae-Wook Koh, Mathew K. Mathai, Chuang Qian, Tsung-Ting Tsai, James P. Landry, Kiran S. Pillai, Injae Hwang, Yongjun Li
  • Publication number: 20220093059
    Abstract: An electronic device may include an electronic display including display pixels to display an image based on compensated image data. The electronic display may also include a stressed reference pixel to exhibit burn-in related aging in response to one or more stress sessions and a non-stressed reference pixel configured to not undergo the one or more stress sessions. Additionally, the electronic device may include image processing circuitry to determine a panel-specific aging profile based on a comparison between one or more properties of the stressed reference pixel and the one or more properties of the non-stressed reference pixel. The image processing circuitry may also generate one or more gain maps based on the panel-specific aging profile and generate the compensated image data by applying the one or more gain maps to input image data.
    Type: Application
    Filed: July 14, 2021
    Publication date: March 24, 2022
    Inventors: Maofeng Yang, Jiayi Jin, David A. Doyle, Yifan Zhang, Weijun Yao, Jiye Lee, Tae-Wook Koh, Mathew K. Mathai, Chuang Qian, Tsung-Ting Tsai, James P. Landry, Kiran S. Pillai, Injae Hwang, Yongjun Li
  • Patent number: 11276369
    Abstract: Systems, methods, and devices are provided to reduce a likelihood of image burn-in on an electronic display. Such an electronic device may include image processing circuitry and an electronic display. The image processing circuitry may receive image data and analyze the image data for risk of image burn-in and, based at least in part on the analysis of the image data, reduce a risk of image burn-in at least in part by reducing a local maximum pixel luminance value in at least one of a plurality of regions of the image data over time or by reducing a dynamic range headroom of the image data. The electronic display may display the image data with a reduced risk of image burn-in on the pixels of the electronic display.
    Type: Grant
    Filed: April 9, 2018
    Date of Patent: March 15, 2022
    Assignee: Apple Inc.
    Inventors: Tobias Jung, Marc Albrecht, Paul S. Drzaic, Tae-Wook Koh, Teun R. Baar, Yifan Zhang, Ramin Samadani, Nicolas P. Bonnier
  • Patent number: 11171313
    Abstract: Display panel stack-up structures are described. In an embodiment, a display panel includes a substrate, a light source, and a multiple layer thin film encapsulation over the light source. In an embodiment, the display panel additionally includes an anti-reflection layer over the light source. In an embodiment, an incoherence layer is located within the thin film encapsulation.
    Type: Grant
    Filed: June 21, 2019
    Date of Patent: November 9, 2021
    Assignee: Apple Inc.
    Inventors: Yifan Zhang, Amin Salehi, Yun Liu, Paul S. Drzaic, Tae-Wook Koh, Chih Jen Yang, Bhadrinarayana Lalgudi Visweswaran, Chieh-Wei Chen
  • Patent number: 11164540
    Abstract: An electronic device may include an electronic display and a display pipeline. The electronic display may include multiple pixels to display images based at least in part on pixel data. The display pipeline may receive image data and process the image data to determine the pixel data. The display pipeline may include burn-in compensation circuitry to apply gains to the image data based at least in part on burn-in statistics to generate the pixel data. The gain to be applied to the image data for a pixel of the electronic display is determined by the burn-in compensation circuitry, based at least in part on an emission duty cycle of the pixel, to compensate the image data for the pixel for burn-in related aging of the pixel.
    Type: Grant
    Filed: December 11, 2019
    Date of Patent: November 2, 2021
    Assignee: Apple, Inc.
    Inventors: Peter F. Holland, Mahesh B. Chappalli, Yifan Zhang, Tae-Wook Koh
  • Patent number: 11145249
    Abstract: A display may include pixels (such as light-emitting diode pixels) that are susceptible aging effects (burn-in). To help avoid visible artifacts caused by burn-in during operation of the display, compensation circuitry may be used to compensate image data for the display. An optical sensor may be included behind the pixels to directly measure pixel brightness levels. The optical sensor may provide optical sensor data from testing operations to the compensation circuitry. The optical sensor may gather data during burn-in testing operations. During the burn-in testing operations, pixel groups including both high-usage pixels and low-usage pixels may sequentially emit light while the optical sensor gathers data. Brightness differences between the high-usage pixels and low-usage pixels may be used to characterize pixel aging in the display and compensate image data to mitigate visible artifacts caused by burn-in. The optical sensor may also gather data during global brightness testing operations.
    Type: Grant
    Filed: July 15, 2020
    Date of Patent: October 12, 2021
    Inventors: Wanglei Han, Akshay Bhat, Michael H. Lim, Kyung Hoae Koo, Jiayi Jin, David A. Doyle, Tae-Wook Koh, Jared S. Price, Yifan Zhang, Mahdi Nezamabadi
  • Publication number: 20210183333
    Abstract: An electronic device may include an electronic display and a display pipeline. The electronic display may include multiple pixels to display images based at least in part on pixel data. The display pipeline may receive image data and process the image data to determine the pixel data. The display pipeline may include burn-in compensation circuitry to apply gains to the image data based at least in part on burn-in statistics to generate the pixel data. The gain to be applied to the image data for a pixel of the electronic display is determined by the burn-in compensation circuitry, based at least in part on an emission duty cycle of the pixel, to compensate the image data for the pixel for burn-in related aging of the pixel.
    Type: Application
    Filed: December 11, 2019
    Publication date: June 17, 2021
    Inventors: Peter F. Holland, Mahesh B. Chappalli, Yifan Zhang, Tae-Wook Koh
  • Patent number: 10991283
    Abstract: A flat-panel display device and method to prevent display panel burn-in through a decimated look-up table with pixel shifting in a display or an augmented reality display.
    Type: Grant
    Filed: May 3, 2019
    Date of Patent: April 27, 2021
    Assignee: Apple Inc.
    Inventors: Sheng Zhang, Chaohao Wang, Michael Slootsky, Yifan Zhang, Tae-Wook Koh
  • Patent number: 10983482
    Abstract: An electronic device such as a wristwatch device or other device may have a display. The display may be used to continuously display information such as watch face information. A watch face image on the display may contain watch face elements such as watch face hands, watch face indices, and complications. To reduce burn-in risk for watch face elements, control circuitry in the electronic device may impose burn-in constraints on attributes of the watch face elements such as peak luminance constraints, dwell time constraints, color constraints, constraints on the shape of each element, and constraints on element style. These constraints may help avoid situations in which static elements such as watch face indices create more burn-in than dynamic elements such as watch face hands.
    Type: Grant
    Filed: February 15, 2019
    Date of Patent: April 20, 2021
    Assignee: Apple Inc.
    Inventors: Tae-Wook Koh, Yiqiang Nie, Yifan Zhang, Giovanni M. Agnoli, Paul S. Drzaic, David A. Doyle
  • Publication number: 20200218204
    Abstract: An electronic device such as a wristwatch device or other device may have a display. The display may be used to continuously display information such as watch face information. A watch face image on the display may contain watch face elements such as watch face hands, watch face indices, and complications. To reduce burn-in risk for watch face elements, control circuitry in the electronic device may impose burn-in constraints on attributes of the watch face elements such as peak luminance constraints, dwell time constraints, color constraints, constraints on the shape of each element, and constraints on element style. These constraints may help avoid situations in which static elements such as watch face indices create more burn-in than dynamic elements such as watch face hands.
    Type: Application
    Filed: February 15, 2019
    Publication date: July 9, 2020
    Inventors: Tae-Wook Koh, Yiqiang Nie, Yifan Zhang, Giovanni M. Agnoli, Paul S. Drzaic, David A. Doyle
  • Publication number: 20200099012
    Abstract: Display panel stack-up structures are described. In an embodiment, a display panel includes a substrate, a light source, and a multiple layer thin film encapsulation over the light source. In an embodiment, the display panel additionally includes an anti-reflection layer over the light source. In an embodiment, an incoherence layer is located within the thin film encapsulation.
    Type: Application
    Filed: June 21, 2019
    Publication date: March 26, 2020
    Inventors: Yifan Zhang, Amin Salehi, Yun Liu, Paul S. Drzaic, Tae-Wook Koh, Chih Jen Yang, Bhadrinarayana Lalgudi Visweswaran, Chieh-Wei Chen
  • Publication number: 20200074900
    Abstract: A flat-panel display device and method to prevent display panel burn-in through a decimated look-up table with pixel shifting in a display or an augmented reality display.
    Type: Application
    Filed: May 3, 2019
    Publication date: March 5, 2020
    Inventors: Sheng Zhang, Chaohao Wang, Michael Slootsky, Yifan Zhang, Tae-Wook Koh
  • Patent number: 10453388
    Abstract: An electronic device may be provided with a display. A content generator may generate frames of image data to be displayed on the display. The display may have an array of pixels that emit light to display images. The pixels may contain light-emitting devices such as organic light-emitting diodes, quantum dot light-emitting diodes, and light-emitting diodes formed from discrete semiconductor dies. As a result of aging, the light producing capabilities of the light-emitting devices may degrade over time. The electronic device may have a temperature sensor that gathers temperature measurements and an ambient light sensor. A pixel luminance degradation compensator may apply compensation factors to uncorrected pixel luminance values associated with the frames of image data to produce corresponding corrected pixel luminance values for the display. The compensation factors may be based on aging history information such as pixel luminance history, ambient light exposure, and temperature measurements.
    Type: Grant
    Filed: April 30, 2018
    Date of Patent: October 22, 2019
    Assignee: Apple Inc.
    Inventors: Jiye Lee, Yifan Zhang, Chieh-Wei Chen, Tae-Wook Koh, Hongwei Chang, Paul S. Drzaic
  • Patent number: 10453375
    Abstract: A data processing system can store a long-term history of pixel luminance values in a secure memory and use those values to create burn-in compensation values that are used to mitigate burn-in effect on a display. The long-term history can be updated over time with new, accumulated pixel luminance values.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: October 22, 2019
    Assignee: Apple Inc.
    Inventors: Paul S. Drzaic, Tae-Wook Koh, Ross Thompson, Guy Cote, Christopher P. Tann, Jerrold V. Hauck, Yifan Zhang, Jean-Pierre Guillou, Ian C. Hendry, Vanessa C. Heppolette, Arthur L. Spence
  • Patent number: 10410569
    Abstract: A data processing system can store a long-term history of pixel luminance values in a secure memory and use those values to create burn-in compensation values that are used to mitigate burn-in effect on a display. The long-term history can be updated over time with new, accumulated pixel luminance values.
    Type: Grant
    Filed: January 18, 2018
    Date of Patent: September 10, 2019
    Assignee: Apple Inc.
    Inventors: Paul S. Drzaic, Ross Thompson, Guy Cote, Christopher P. Tann, Jerrold V. Hauck, Yifan Zhang, Jean-Pierre Guillou, Ian C. Hendry, Vanessa C. Heppolette, Tae-Wook Koh, Arthur L. Spence