Patents by Inventor Kingsuk Brahma

Kingsuk Brahma 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: 11127357
    Abstract: Techniques for implementing and/or operating an electronic device, which includes a display pixel that emits light to facilitate displaying an image during an emission period and a data driver coupled to the display pixel via a data line. The data driver generates a data line voltage signal based on image data that indicates target luminance of the display pixel in the image and supplies the data line voltage signal to the data line during a non-emission period preceding the emission period to facilitate writing the image to the display pixel. Additionally, the data driver supplies an intermediate voltage greater than a ground voltage to the data line during the emission period in which the image is displayed to facilitate reducing luminance variation in the image resulting from a leakage current flowing between an internal node of the display pixel and the data line during the emission period.
    Type: Grant
    Filed: April 16, 2020
    Date of Patent: September 21, 2021
    Assignee: APPLE INC.
    Inventors: Jie Won Ryu, Myungjoon Choi, Hyunsoo Kim, Hyunwoo Nho, Chin-Wei Lin, Shiping Shen, Kingsuk Brahma, Chaohao Wang, Shinya Ono, Alex H. Pai, Hassan Edrees
  • Publication number: 20210150950
    Abstract: Electronic devices and methods for compensating for aging or other effects in a display during a non-transmitting state (off state) of the display. Sensing may include emissive element sensing of the display and/or thin film transistor sensing of the display. Compensating for the effects may preserve or increase a uniformity of transmission of the display.
    Type: Application
    Filed: August 31, 2018
    Publication date: May 20, 2021
    Inventors: Chin-Wei Lin, Hung Sheng Lin, Hyunsoo Kim, Hyunwoo Nho, Injae Hwang, Jesse A. Richmond, Jie Won Ryu, Junhua Tan, Kavinaath Murugan, Kingsuk Brahma, Shengkui Gao, Shiping Shen, Sun-Il Chang, Myung-Je Cho, Yafei Bi
  • Patent number: 10997914
    Abstract: A system may include a display panel that includes number of pixels that display image data on a display. The system may also include a circuit that measures a voltage associated with a light-emitting diode (LED) of a pixel of the number of pixels in response to the LED receiving a current. In addition to the circuit, the system may employ data processing circuitry that may generate a calibrated prediction model based at least in part on the voltage and the current, such that the calibrated prediction model predicts a change in voltage performance of the LED as the LED ages.
    Type: Grant
    Filed: September 6, 2019
    Date of Patent: May 4, 2021
    Assignee: Apple Inc.
    Inventors: Injae Hwang, Jiye Lee, Yifan Zhang, Hyunwoo Nho, Sun-Il Chang, Junhua Tan, Jie Won Ryu, Hyunsoo Kim, Myungjoon Choi, Shiping Shen, Kingsuk Brahma, Jesse A. Richmond
  • Publication number: 20210118349
    Abstract: An electronic display may include pixel circuitry to display an image based on image data compensated for voltage variations within the pixel circuitry. Image processing circuitry may generate a compensation value to compensate the image data for cross-talk (e.g., electromagnetic coupling between an electrode of touch sensor circuitry and an electrode of the pixel circuitry) that may cause the voltage variations. Additionally or alternatively, the image processing circuitry may generate another compensation value to compensate the image data for another cross-talk (e.g., electromagnetic coupling between two electrodes of the pixel circuitry). The image processing circuitry may generate the compensated image data based on the first compensation value and/or the second compensation value.
    Type: Application
    Filed: September 9, 2020
    Publication date: April 22, 2021
    Inventors: Myungjoon Choi, Kingsuk Brahma, Li-Xuan Chuo, Mohammad Ali Jangda, Hyunsoo Kim, Hyunwoo Nho, Alex H. Pai, Jesse Aaron Richmond, Jie Won Ryu, Shiping Shen, Chaohao Wang
  • Publication number: 20210082349
    Abstract: An electronic device comprises a controller. The controller is configured to provide a first signal to a display of the electronic device to turn off the display. The controller is also configured to provide a second signal to the display to alter a gate source voltage of a drive transistor coupled to a light emitting diode (LED) of a pixel of the display while the display is turned off.
    Type: Application
    Filed: March 27, 2018
    Publication date: March 18, 2021
    Inventors: Junhua Tan, Kingsuk Brahma, Jie Won Ryu, Shengkui Gao, Shiping Shen, Majid Gharghi, Hyunwoo Nho, Injae Hwang, Kavinaath Murugan, Sun-II Chang, Chin-Wei Lin, Hyunsoo Kim, Rui Zhang, Jesse Aaron Richmond, Yun Wang, Hung Sheng Lin
  • Patent number: 10950182
    Abstract: The present disclosure relates generally to systems and methods that may reduce a reduction in visual artifacts related to hysteresis of a light emitting diode (LED) electronic display. In one example, an electronic device may include a controller. The controller is may provide a signal to a pixel of a display of the electronic device while at least a portion of the display is turned off. The signal may include a first current and a second current. The first current may be designed to increase an ambient temperature corresponding to the pixel. The second current may be generated as part of an active panel conditioning operation. By applying the first current and the second current, hysteresis settling times from the pixel may improve, therefore improving speeds of sensing and compensation operations of the electronic device.
    Type: Grant
    Filed: September 11, 2019
    Date of Patent: March 16, 2021
    Assignee: Apple Inc.
    Inventors: Junhua Tan, Kingsuk Brahma, Jie Won Ryu, Shengkui Gao, Shiping Shen, Majid Gharghi, Hyunwoo Nho, Injae Hwang, Kavinaath Murugan, Sun-Il Chang, Chin-Wei Lin, Hyunsoo Kim, Rui Zhang, Jesse Aaron Richmond, Yun Wang, Hung Sheng Lin, Alex H. Pai, Chaohao Wang, Wei H. Yao
  • Patent number: 10943541
    Abstract: Current-voltage shift determination circuitry of a processing core complex coupled to the electronic display determines total current-voltage shift values at a pixel. The current-voltage shift determination circuitry then determines temperature-based current-voltage shift values at the pixel. The current-voltage shift determination circuitry extracts the temperature-based current-voltage shift values from the total current-voltage shift values to determine age-based voltage degradation values. Display compensation circuitry of the processing core complex adjusts display of image data by the pixel based on the age-based voltage degradation values. In this manner, voltage degradation due to pixel aging may be determined separately from current-voltage shift due to temperature, and, as such, be more accurately compensated for, resulting in better display of image data.
    Type: Grant
    Filed: August 29, 2019
    Date of Patent: March 9, 2021
    Assignee: Apple Inc.
    Inventors: Junhua Tan, Hsin-Ying Chiu, Sun-Il Chang, Yunhui Hou, Jie Won Ryu, Hyunwoo Nho, Weichuan Yao, Shiping Shen, Injae Hwang, Hyunsoo Kim, Myungjoon Choi, Shengkui Gao, Chaohao Wang, Kingsuk Brahma, Jesse Aaron Richmond, Myung-Je Cho, Changki Min, Wei H. Yao
  • Publication number: 20210056930
    Abstract: An electronic device may include an electronic display having multiple display pixels. The display pixels may illuminate at a target luminance based at least in part on a first analog voltage signal. The electronic device may also include an electrical bus configured to generate multiple analog voltage signals including the first analog voltage signal, which is output on an output of the electrical bus. The electrical bus may include a digital to analog converter to generate at least some of the analog voltage signals and multiple output buffers to buffer the analog voltage signals. The outputs may be buffered by an output buffer of the output buffers.
    Type: Application
    Filed: July 14, 2020
    Publication date: February 25, 2021
    Inventors: Jaeyoung Kang, Jesse Aaron Richmond, Mahdi Farrokh Baroughi, Hopil Bae, John T. Wetherell, Kingsuk Brahma, Yuichi Okuda, Shingo Hatanaka, Baris Cagdaser, Myungjoon Choi, Jie Won Ryu, Hyunwoo Nho, Yafei Bi, Wei H. Yao, Henry C. Jen, Derek Keith Shaeffer
  • Publication number: 20210012712
    Abstract: A display may include an array of organic light-emitting diode display pixels having transistors characterized by threshold voltages subject to transistor variations. Compensation circuitry may be used to sense a current from selected display pixels. A display pixel may include a drive transistor, a gate setting transistor for driving a reference voltage onto the gate terminal of the drive transistor, a data loading and current sensing transistor for connecting the drive transistor to a data/current-sensing line, a light-emitting diode, an emission control transistor coupled between the drive transistor and the diode, and an anode resetting transistor for selectively resetting the anode terminal of the diode. During in-frame current sensing operations, the emission control transistor may be turned off to decouple the drive transistor from the diode, thereby blocking off any residue current and lateral leakage current that may be present at the diode.
    Type: Application
    Filed: September 28, 2018
    Publication date: January 14, 2021
    Inventors: Chin-Wei Lin, Fan Gui, Hung Sheng Lin, Hyunwoo Nho, Jie Won Ryu, Junhua Tan, Kingsuk Brahma, Majid Gharghi, Mohammad Reza Esmaeili Rad, Shinya Ono, Yun Wang, Zino Lee
  • Patent number: 10878747
    Abstract: Methods and systems for compensating a display of an electronic device using internal sensing and external compensation. The external compensation uses a generated compensation map that then is used to compensate for variations that occur outside of display circuitry. The internal sensing compensation is used to compensate for internally sensed parameters (e.g., aging) of the display.
    Type: Grant
    Filed: July 9, 2019
    Date of Patent: December 29, 2020
    Assignee: Apple Inc.
    Inventors: Shengkui Gao, Chaohao Wang, Hung Sheng Lin, Hyunsoo Kim, Hyunwoo Nho, Injae Hwang, Jesse Aaron Richmond, Jie Won Ryu, Junhua Tan, Kingsuk Brahma, Myung-Je Cho, Myungjoon Choi, Shiping Shen, Sun-Il Chang, Wei H. Yao, Yi Qiao
  • Publication number: 20200388225
    Abstract: Systems and methods are presently disclosed that compensate for temperature-based parasitic capacitance variation of a pixel of a display by causing a driver transistor of the pixel to enter an ohmic or linear region. A lookup table is generated based on temperatures at the pixel, diode voltages, and target diode currents or luminances at a diode of the pixel. A correction voltage is determined based on a target diode current or luminance, a temperature at the pixel, and the lookup table. A data voltage is applied corresponding to the target diode current or luminance and the correction voltage to the driver transistor.
    Type: Application
    Filed: June 9, 2020
    Publication date: December 10, 2020
    Inventors: Hyunsoo Kim, Injae Hwang, Jesun Kim, Jesse A. Richmond, Junhua Tan, Jie Won Ryu, Hyunwoo Nho, Kingsuk Brahma, Chaohao Wang, Shiping Shen, Myungjoon Choi, Myung-Je Cho, Rebecca Park, Sun-Il Chang
  • Publication number: 20200365082
    Abstract: A current-voltage (IV) relationship of a pixel having a diode is initially determined. A first voltage is determined that does not cause the diode to emit light, and a first current across the diode is sensed by applying the first voltage. A predetermined current is determined based on the first voltage and the IV relationship. A ratio is determined based on the first current, a target current, and the predetermined current. A ratio voltage is determined by applying the ratio to a predetermined target voltage. If the first current is less than the predetermined current, then the ratio voltage is applied to supply a target current to the diode. If the first current is greater than the predetermined current, then a second voltage is determined by averaging the first test voltage and the ratio voltage, and the second voltage is applied to supply the target current to the diode.
    Type: Application
    Filed: April 15, 2020
    Publication date: November 19, 2020
    Inventors: Injae Hwang, Jesun Kim, Hyunwoo Nho, Jie Won Ryu, Hyunsoo Kim, Junhua Tan, Myungjoon Choi, Rebecca Park, Shiping Shen, Sun-Il Chang, Shengkui Gao, Kingsuk Brahma, Jesse Aaron Richmond, Changki Min, Yifan Zhang, Jiye Lee, Chaohao Wang
  • Patent number: 10839753
    Abstract: A display may have rows and columns of pixels. Gate lines may be used to supply gate signals to rows of the pixels. Data lines may be used to supply data signals to columns of the pixels. The data lines may include alternating even and odd data lines. Data lines may be organized in pairs each of which includes one of the odd data lines and an adjacent one of the even data lines. Demultiplexer circuitry may be configured dynamically during data loading and pixel sensing operations. During data loading, data from display driver circuitry may be supplied, alternately to odd pairs of the data lines and even pairs of the data lines. During sensing, the demultiplexer circuitry may couple a pair of the even data lines to sensing circuitry in the display driver circuitry and then may couple a pair of the odd data lines to the sensing circuitry.
    Type: Grant
    Filed: September 18, 2018
    Date of Patent: November 17, 2020
    Assignee: Apple Inc.
    Inventors: Chin-Wei Lin, Majid Gharghi, Mohammad Reza Esmaeili Rad, Yun Wang, Jie Won Ryu, Kingsuk Brahma, Shingo Hatanaka, Shinya Ono, Ting-Kuo Chang
  • Publication number: 20200335040
    Abstract: An electronic device includes a display having multiple regions of pixels. Each pixel includes a diode that emits light based on an amount of current through the diode and a transistor that controls the amount of current flowing through the diode. The electronic device includes driver-integrated circuitry that reduces hysteresis in a first transistor of a first pixel of a region of pixels, settles a threshold voltage of the first transistor, applies a test voltage to the first transistor, and senses a current across the first transistor. The electronic device includes processing circuitry that determines a predetermined voltage based on the current and a predetermined current-voltage relationship determined at an initial temperature, determines a voltage difference between the test voltage and the predetermined voltage, and applies the predetermined voltage and the voltage difference to a second transistor of a second pixel of the region of pixels.
    Type: Application
    Filed: February 26, 2020
    Publication date: October 22, 2020
    Inventors: Hyunwoo Nho, Myungjoon Choi, Hyunsoo Kim, Mohammad Ali Jangda, Jie Won Ryu, Shiping Shen, Kingsuk Brahma, Chaohao Wang, Wei H. Yao, Alex H. Pai
  • Publication number: 20200335046
    Abstract: Techniques for implementing and/or operating an electronic device, which includes a display pixel that emits light to facilitate displaying an image during an emission period and a data driver coupled to the display pixel via a data line. The data driver generates a data line voltage signal based on image data that indicates target luminance of the display pixel in the image and supplies the data line voltage signal to the data line during a non-emission period preceding the emission period to facilitate writing the image to the display pixel. Additionally, the data driver supplies an intermediate voltage greater than a ground voltage to the data line during the emission period in which the image is displayed to facilitate reducing luminance variation in the image resulting from a leakage current flowing between an internal node of the display pixel and the data line during the emission period.
    Type: Application
    Filed: April 16, 2020
    Publication date: October 22, 2020
    Inventors: Jie Won Ryu, Myungjoon Choi, Hyunsoo Kim, Hyunwoo Nho, Chin-Wei Lin, Shiping Shen, Kingsuk Brahma, Chaohao Wang, Shinya Ono, Alex H. Pai, Hassan Edrees
  • Publication number: 20200302856
    Abstract: A system includes an electronic display panel that has a plurality of pixels configured to depict frames of image data. The electronic display also includes display driver circuitry configured to, for a first frame of image data representing first image content, modify a gate-to-source voltage of a transistor of a first pixel of the plurality of pixels to a content-dependent first gate-to-source voltage. Additionally, after modifying the gate-to-source voltage to the first gate-to-source voltage, the display driver circuitry is configured to program the first pixel by modifying the gate-to-source voltage to a gate-to-source programming voltage that differs from the first gate-to-source voltage and is based on image data associated with the pixel from the first frame of the image data. Furthermore, the display driver circuitry is configured to cause the plurality of pixels to emit light.
    Type: Application
    Filed: January 17, 2020
    Publication date: September 24, 2020
    Inventors: Xin Lin, Yun Wang, Chin-Wei Lin, Majid Gharghi, Fan Gui, Chen-Ming Chen, Jie Won Ryu, Hyunwoo Nho, Alex H. Pai, Kingsuk Brahma, Junhua Tan, Szu Heng Tseng
  • Patent number: 10777106
    Abstract: An electronic device includes a display having a number of pixels, source driving circuitry that drives data to the pixels, and data lines that communicatively couple the source driving circuitry with the pixels. The electronic device also includes quality monitoring and calibration circuitry that identifies degradation in the source driving circuitry, one or more of the data lines, or both. The electronic device may be controlled based at least in part upon identification of the degradation.
    Type: Grant
    Filed: September 27, 2017
    Date of Patent: September 15, 2020
    Assignee: Apple Inc.
    Inventors: Hung Sheng Lin, Jie Won Ryu, Kingsuk Brahma, Hyunwoo Nho, Baris Cagdaser, Junhua Tan, Sun-Il Chang, Luigi Panseri, Injae Hwang, Jesse A. Richmond, Toshiaki Sawada, Hyuck-Jae Lee
  • Patent number: 10755618
    Abstract: Systems and methods are provided for differential sensing (DS), difference-differential sensing (DDS), correlated double sampling (CDS), correlated-correlated double sampling (CDS-CDS) and/or programmable capacitor matching to reduce display panel sensing noise. An electronic device may include one or more processors that generate image data according to sensing operations. The one or more processors may reference a sensing pattern as part of sensing operations. Applying test sensing signals based on the sensing pattern may help reduce error associated with sensing operations.
    Type: Grant
    Filed: April 19, 2019
    Date of Patent: August 25, 2020
    Assignee: Apple Inc.
    Inventors: Hung Sheng Lin, Shengkui Gao, Hyunwoo Nho, Chin-Wei Lin, Mohammad B. Vahid Far, Jie Won Ryu, Kingsuk Brahma, Junhua Tan, Sun-Il Chang, Shinya Ono, Jesse Aaron Richmond, Yafei Bi, Derek K. Shaeffer, Myungjoon Choi, Shiping Shen
  • Patent number: 10642083
    Abstract: Electronic devices and methods for compensating for temperature-dependent fluctuations in a display include receiving a temperature index may be received from a sensor and/or calculations that indicates a temperature of the system, a pixel, a panel, a grid of a panel, or a combination thereof. The temperature is used to predict a voltage change across an emissive element (VHILO), such as an organic light emitting diode (OLED). This predicted voltage change is then compensated for before emission.
    Type: Grant
    Filed: June 14, 2018
    Date of Patent: May 5, 2020
    Assignee: Apple Inc.
    Inventors: Injae Hwang, Rui Zhang, Hung Sheng Lin, Hyunsoo Kim, Hyunwoo Nho, Jesse A. Richmond, Jie Won Ryu, Junhua Tan, Kingsuk Brahma, Shengkui Gao, Shiping Shen, Sun-Il Chang
  • Publication number: 20200118486
    Abstract: An electronic device comprises an electronic display having an active area having a pixel. The electronic device also comprises processing circuitry configured to receive image data to send to the pixel and adjust the image data to generate corrected image data based at least in part on a stored correction value for the pixel. The processing circuitry also is configured to generate a test data to send to the pixel subsequent to sending corrected image data to the pixel, wherein the test data is selected based upon a comparison of at least one aspect of the corrected image data with a threshold value.
    Type: Application
    Filed: March 27, 2018
    Publication date: April 16, 2020
    Inventors: Hung Sheng Lin, Hyunwoo Nho, Sun-Il Chang, Junhua Tan, Jie Won Ryu, Shengkui Gao, Rui Zhang, Injae Hwang, Kingsuk Brahma, Jesse Aaron Richmond, Shiping Shen, Hyunsoo Kim