Patents by Inventor Christopher P. Tann

Christopher P. Tann 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: 10762820
    Abstract: System and method for improving displayed image quality of an electronic display that displays a first image frame by applying a first voltage to a display pixel and a second image frame directly before the first image frame by applying a second voltage to the display pixel. A display pipeline is communicatively coupled to the electronic display and receives first image data corresponding with the first image frame, where the image data includes a first grayscale value corresponding with the display pixel. Additionally the display pipeline determines an inversion balancing grayscale offset based at least in part on the first grayscale value when polarity of the first voltage and polarity of the second voltage are the same and determines magnitude of the first voltage by applying the inversion balancing grayscale offset to the first grayscale value to reduce likelihood of a perceivable luminance spike when displaying the first image frame.
    Type: Grant
    Filed: February 6, 2019
    Date of Patent: September 1, 2020
    Assignee: Apple Inc.
    Inventors: Christopher P. Tann, Taesung Kim, Sandro H. Pintz
  • Patent number: 10706825
    Abstract: Systems, apparatuses, and methods for implementing a timestamp based display update mechanism. A display control unit includes a timestamp queue for storing timestamps, wherein each timestamp indicates when a corresponding frame configuration set should be fetched from memory. At pre-defined intervals, the display control unit may compare the timestamp of the topmost entry of the timestamp queue to a global timer value. If the timestamp is earlier than the global timer value, the display control unit may pop the timestamp entry and fetch the frame next configuration set from memory. The display control unit may then apply the updates of the frame configuration set to its pixel processing elements. After applying the updates, the display control unit may fetch and process the source pixel data and then drive the pixels of the next frame to the display.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: July 7, 2020
    Assignee: Apple Inc.
    Inventors: Brijesh Tripathi, Arthur L. Spence, Joshua P. de Cesare, Ilie Garbacea, Guy Cote, Mahesh B. Chappalli, Malcolm D. Gray, Christopher P. Tann
  • Patent number: 10699622
    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: June 30, 2020
    Assignee: APPLE INC.
    Inventors: Ross Thompson, Guy Cote, Christopher P. Tann, Jerrold V. Hauck, Ian C. Hendry, Vanessa C. Heppolette, Adam J. Machalek, Alan M. Dunn, Ali Sazegari, Lars M. Lindberg, Arthur L. Spence
  • Patent number: 10643555
    Abstract: Devices and methods for useful in providing localized synchronized and/or dynamic in-band internal gamma code adjustment per frame period are provided. By way of example, a display panel includes a data driver, which includes a first DAC configured to provide an internal gamma voltage signal to cause a first adjustment to an image data signal. The first adjustment is configured to selectively adjust the image data signal based at least in part on a refresh rate or a frame rate of the display panel. The data driver includes a second DAC coupled to the first DAC and configured to provide an external gamma voltage signal configured to provide a second adjustment to the image data signal, and an output buffer configured to supply the image data signal to pixels of the display panel, wherein the image data signal comprises the first adjustment and the second adjustment.
    Type: Grant
    Filed: September 7, 2017
    Date of Patent: May 5, 2020
    Assignee: Apple Inc.
    Inventors: Fenghua Zheng, Christopher P. Tann, Sandro H. Pintz, David S. Zalatimo, Jun Qi, Zhibing Ge
  • Patent number: 10643572
    Abstract: An electronic device may include a display panel to display an image and a display pipeline to process image data for the image. The display pipeline may include a controller to determine a first potential presentation time based on a maximum refresh rate of the display panel. The controller may also determine if a second target presentation time of a second image is equal to the first potential presentation time before a pipeline configuration time, and if the second target presentation time of the second image is equal to a second potential presentation time that occurs after the first potential presentation time and before a first pre-notification time occurring before the pipeline configuration time. The controller may output a first pre-notification signal at the first pre-notification time that instructs the display panel to pause self-refreshes until after the second image is displayed.
    Type: Grant
    Filed: September 11, 2018
    Date of Patent: May 5, 2020
    Assignee: Apple Inc.
    Inventors: Peter F. Holland, Arthur L. Spence, Christopher P. Tann
  • Patent number: 10600379
    Abstract: The disclosure describes procedures for dynamically employing a variable refresh rate at an LCD display of a consumer electronic device, such as a laptop computer, a tablet computer, a mobile phone, or a music player device. In some configurations, the consumer electronic device can include a host system portion, having one or more processors and a display system portion, having a timing controller, a buffer circuit, a display driver, and a display panel. The display system can receive image data and image control data from a GPU of the host system, evaluate the received image control data to determine a reduced refresh rate (RRR) for employing at the display panel, and then transition to the RRR, whenever practicable, to conserve power. In some scenarios, the transition to the RRR can be a transition from a LRR of 50 hertz or above to a RRR of 40 hertz or below.
    Type: Grant
    Filed: August 14, 2018
    Date of Patent: March 24, 2020
    Assignee: Apple Inc.
    Inventors: Prasanna Nambi, Jason N. Gomez, Fenghua Zheng, Paolo Sacchetto, Sandro H. Pintz, Taesung Kim, Christopher P. Tann, Marc Albrecht, David W. Lum
  • Publication number: 20200082783
    Abstract: An electronic device may include a display panel to display an image and a display pipeline to process image data for the image. The display pipeline may include a controller to determine a first potential presentation time based on a maximum refresh rate of the display panel. The controller may also determine if a second target presentation time of a second image is equal to the first potential presentation time before a pipeline configuration time, and if the second target presentation time of the second image is equal to a second potential presentation time that occurs after the first potential presentation time and before a first pre-notification time occurring before the pipeline configuration time. The controller may output a first pre-notification signal at the first pre-notification time that instructs the display panel to pause self-refreshes until after the second image is displayed.
    Type: Application
    Filed: September 11, 2018
    Publication date: March 12, 2020
    Inventors: Peter F. Holland, Arthur L. Spence, Christopher P. Tann
  • Publication number: 20200064902
    Abstract: The configuration buffer may be divided into partitions that may effectively function as multiple linked configuration buffers. The linked partitions may each be associated with a portion of the display pipeline (e.g., an image process block) and may each be responsible for loading configuration entries into the programmable register(s) of a portion of the display pipeline. In this manner, the partitions may load the associated programmable register(s) of the display pipeline substantially simultaneously, reducing the time used to configure the entire display pipeline. Since configuration of the display pipeline may occur during the blanking period, a reduction in display pipeline configuration time may reduce the blanking period and increase the time for driving pixels of the display, thereby improving perceived image quality (e.g., pixel yield of the display panel).
    Type: Application
    Filed: August 23, 2018
    Publication date: February 27, 2020
    Inventors: Peter F. Holland, Christopher P. Tann, Malcolm D. Gray, Hari Ganesh R. Thirunageswaram, Kristan Jon Monsen
  • Patent number: 10482806
    Abstract: Devices and methods for reducing or eliminating spatiotemporal dithering image artifacts are provided. By way of example, a method includes providing positive polarity and negative polarity data signals to a plurality of pixels of a display during a first frame period, in which the first frame period corresponds a first spatiotemporal rotation phase. The method includes providing the positive polarity signals and the negative polarity signals to the plurality of pixels of the display during a second frame period, in which the second frame period corresponds a second spatiotemporal rotation phase. A spatiotemporal rotation phase sequence provided to the display comprises the first spatiotemporal rotation phase and the second spatiotemporal rotation phase. One of the first spatiotemporal rotation phase and the second spatiotemporal rotation phase of the spatiotemporal rotation phase sequence is altered during the first frame period or the second time period.
    Type: Grant
    Filed: March 2, 2015
    Date of Patent: November 19, 2019
    Assignee: Apple Inc.
    Inventors: Marc Albrecht, David S. Zalatimo, Christopher P. Tann, Sandro H. Pintz
  • 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: 10438561
    Abstract: Systems and methods for interpolating overdrive values using a lookup table to compensate for potential display artifacts. Interpolating includes applying a first interpolation type to a first portion of the lookup table when a point to be interpolated is in the first portion of the lookup table. However, interpolating includes applying a second interpolation type to a second portion of the lookup table when the point to be interpolated is in the second portion of the lookup table. The interpolated values are then used to drive pixels of a display panel.
    Type: Grant
    Filed: December 14, 2017
    Date of Patent: October 8, 2019
    Assignee: Apple Inc.
    Inventors: Shereef Shehata, Christopher P. Tann, Guy Côté
  • 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
  • Patent number: 10410568
    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
  • Patent number: 10403192
    Abstract: Devices and methods for error diffusion and spatiotemporal dithering are provided. By way of example, a method of operating a display includes receiving a pixel input, a set of pixel coordinates, and a current frame number. A kernel and a particular kernel bit of the kernel is selected from a set of kernels, based upon the pixel input, the pixel coordinates, the frame number, or any combination thereof. A dithered output is determined based at least in part upon the kernel bit. When the display is in a diamond pixel configuration, the dithered output is applied in accordance with a diamond pattern formed by red, blue, or red and blue pixel channels.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: September 3, 2019
    Assignee: Apple Inc.
    Inventors: Marc Albrecht, Mahesh B. Chappalli, Christopher P. Tann, Jim C. Chou, Guy Cote
  • Publication number: 20190189082
    Abstract: Systems and methods for interpolating overdrive values using a lookup table to compensate for potential display artifacts. Interpolating includes applying a first interpolation type to a first portion of the lookup table when a point to be interpolated is in the first portion of the lookup table. However, interpolating includes applying a second interpolation type to a second portion of the lookup table when the point to be interpolated is in the second portion of the lookup table. The interpolated values are then used to drive pixels of a display panel.
    Type: Application
    Filed: December 14, 2017
    Publication date: June 20, 2019
    Inventors: Shereef Shehata, Christopher P. Tann, Guy Côté
  • Publication number: 20190172380
    Abstract: System and method for improving displayed image quality of an electronic display that displays a first image frame by applying a first voltage to a display pixel and a second image frame directly before the first image frame by applying a second voltage to the display pixel. A display pipeline is communicatively coupled to the electronic display and receives first image data corresponding with the first image frame, where the image data includes a first grayscale value corresponding with the display pixel. Additionally the display pipeline determines an inversion balancing grayscale offset based at least in part on the first grayscale value when polarity of the first voltage and polarity of the second voltage are the same and determines magnitude of the first voltage by applying the inversion balancing grayscale offset to the first grayscale value to reduce likelihood of a perceivable luminance spike when displaying the first image frame.
    Type: Application
    Filed: February 6, 2019
    Publication date: June 6, 2019
    Inventors: Christopher P. Tann, Taesung Kim, Sandro H. Pintz
  • Patent number: 10276085
    Abstract: This application relates to systems, methods, and apparatus for compensating voltage for pixels of a display panel based on the location of the pixels within the display panel. An amount of voltage compensation is assigned to each pixel or a group of pixels within the display panel in accordance with a calibration of the display panel. During operation of the display panel, pixel data is generated for a location of the display panel, and the pixel data is modified according to the amount of voltage compensation corresponding to the location. By modifying the pixel data in this way, spatial variations in voltage across the display panel can be mitigated in order to reduce the occurrence of certain display artifacts at the display panel.
    Type: Grant
    Filed: December 17, 2015
    Date of Patent: April 30, 2019
    Assignee: Apple Inc.
    Inventors: Chaohao Wang, Paolo Sacchetto, Marc Albrecht, Christopher P. Tann, Shih-Chyuan Fan Jiang, Howard H. Tang, James E. C. Brown, Zhibing Ge
  • Patent number: 10261632
    Abstract: One embodiment describes an electronic display that includes display driver circuitry that displays at least a first image frame and a second image frame on the electronic device using a first display pixel and a second display pixel. A timing controller of the electronic display determines at least a first insertion time for a first intra-frame pause for the first image frame and a second insertion time for a second intra-frame pause for the second image frame, which pause rendering of image data to allow the touch sensing circuitry to detect user interaction. The insertion times for the first and second intra-frame pauses are varied from one another by a determined step size.
    Type: Grant
    Filed: July 20, 2017
    Date of Patent: April 16, 2019
    Assignee: APPLE INC.
    Inventors: Peter F. Holland, Christopher P. Tann, Malcolm D. Gray
  • Publication number: 20190080666
    Abstract: An electronic display pipeline may process image data for display on an electronic display. The electronic display pipeline may include burn-in compensation statistics collection circuitry and burn-in compensation circuitry. The burn-in compensation statistics collection circuitry may collect image statistics based at least in part on the image data. The statistics may estimate a likely amount of non-uniform aging of the sub-pixels of the electronic display. The burn-in compensation circuitry may apply a gain to sub-pixels of the image data to account for non-uniform aging of corresponding sub-pixels of the electronic display. The applied gain may be based at least in part on the image statistics collected by the burn-in compensation statistics collection circuitry.
    Type: Application
    Filed: January 3, 2018
    Publication date: March 14, 2019
    Inventors: Mahesh B. Chappalli, Christopher P. Tann, Peter F. Holland, Guy Côté, Stephan Lachowsky
  • Patent number: 10229622
    Abstract: System and method for improving displayed image quality of an electronic display that displays a first image frame by applying a first voltage to a display pixel and a second image frame directly before the first image frame by applying a second voltage to the display pixel. A display pipeline is communicatively coupled to the electronic display and receives first image data corresponding with the first image frame, where the image data includes a first grayscale value corresponding with the display pixel. Additionally the display pipeline determines an inversion balancing grayscale offset based at least in part on the first grayscale value when polarity of the first voltage and polarity of the second voltage are the same and determines magnitude of the first voltage by applying the inversion balancing grayscale offset to the first grayscale value to reduce likelihood of a perceivable luminance spike when displaying the first image frame.
    Type: Grant
    Filed: November 14, 2017
    Date of Patent: March 12, 2019
    Assignee: Apple Inc.
    Inventors: Christopher P. Tann, Taesung Kim, Sandro H. Pintz