Patents by Inventor Yafei Bi

Yafei Bi 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: 10223965
    Abstract: Provided herein are systems and methods for measurement and compensation of display panel current leakage and/or display panel noise. A pixel data signal is received at sensing and compensation circuitry. Current leakage compensation circuitry compensates for current leakage of the display panel in the data signal, while panel noise mitigation circuitry configured to reduce panel noise from the data signal. After compensating for the current leakage and reducing the panel noise, the data signal is provided to downstream circuitry for subsequent processing.
    Type: Grant
    Filed: September 21, 2016
    Date of Patent: March 5, 2019
    Assignee: APPLE INC.
    Inventors: Yafei Bi, Mohammad B. Vahid Far
  • Patent number: 10217402
    Abstract: Methods and devices useful in compensating for VDD and VTH variations in a micro light-emitting diode (micro-LED) display are provided. By way of example, an LED driver includes a first transistor having a first source coupled to an upper voltage rail (VDD), a first gate, and a first drain. The LED driver includes a second transistor having a second source coupled to the first drain of the first transistor, a second gate, and a second drain coupled to the LED. The second transistor is configured to receive the drive current signal from the first transistor and supply the drive current signal to the LED. The LED driver includes compensation circuitry configured to adjust the drive current signal such that the drive current signal is independent of the upper voltage rail (VDD) and a threshold voltage (VTH) of the first transistor or the second transistor.
    Type: Grant
    Filed: August 25, 2016
    Date of Patent: February 26, 2019
    Assignee: Apple Inc.
    Inventors: Mohammad B. Vahid Far, Yafei Bi, Shinya Ono, Hopil Bae, Chieh-Chien Lin, Hasan Akyol, Xiaofeng Wang
  • Patent number: 10200059
    Abstract: A device includes a resistor string that includes a plurality resistors with voltage taps disposed therebetween. The device may select one particular voltage tap of the plurality of voltage taps based on received gray level data for a pixel of a display. The device also includes a first amplifier that may be coupled to a first terminal end of the resistor string. The device additionally includes a second amplifier that may be coupled to a second terminal end of the resistor string, wherein the plurality of voltage taps may each supply a tap voltage derived from a voltage between the first amplifier and the second amplifier, wherein any tap amplifier of the device coupled to a voltage tap of the plurality of voltage taps provides a reference voltage thereto.
    Type: Grant
    Filed: September 6, 2017
    Date of Patent: February 5, 2019
    Assignee: APPLE INC.
    Inventors: Baris Cagdaser, Derek K. Shaeffer, Hopil Bae, Jesse Aaron Richmond, Jie Won Ryu, Kingsuk Brahma, Mohammad B. Vahid Far, Shingo Hatanaka, Yafei Bi, Yuichi Okuda
  • Publication number: 20190027114
    Abstract: In situations with reduced image changes, display panels, such as the ones disclosed herein, may reduce their power consumption by performing self-refresh cycles, in which they may display locally stored data in the display panel instead of retrieving it from an image buffer. Methods and circuitry for management of the self-refresh cycle may reduce jitter, luminance errors, and/or flickers that may be caused by untimely self-refresh cycles that may occur as a result of latency in the image buffer. In some implementations, the display panel may have a dedicated low latency input that notifies an arrival of an incoming image. In some implementations, the self-refresh cycles of the panel may be managed by a host or a buffer that is responsible for sending the images.
    Type: Application
    Filed: September 27, 2017
    Publication date: January 24, 2019
    Inventors: Yue Jack Chu, Christopher P. Tann, Arthur L. Spence, Brad W. Simeral, Yafei Bi, Jiayi Jin, Ruo-Gu Huang, Haifeng Li, Weijun Yao, Chaohao Wang
  • Publication number: 20190019459
    Abstract: An electronic device includes a display panel. The display panel includes a number of pixels, each of which includes a driving thin-film-transistor (TFT) and a light-emitting diode. Compensation circuitry external to the display panel applies offset data to pixel data for each pixel of the plurality of pixels before the pixel data is provided to the plurality of pixels.
    Type: Application
    Filed: September 19, 2018
    Publication date: January 17, 2019
    Inventors: Mohammad B. Vahid Far, Jesse A. Richmond, Yafei Bi
  • Patent number: 10157590
    Abstract: An electronic device may have a display with an array of pixels. The device may have an array of components such as an array of light sensors for capturing fingerprints of a user through an array of corresponding transparent windows in the display. A capacitive touch sensor, proximity sensor, force sensor, or other sensor may be used by control circuitry in the device to monitor for the presence of a user's finger over the array of light sensors. In response, the control circuitry can direct the display to illuminate a subset of the pixels, thereby illuminating the user's finger and causing reflected light from the finger to illuminate the array of light sensors for a fingerprint capture operation. The display may have display driver circuitry that facilitates the momentary illumination of the subset of pixels with uniform flash data while image data is displayed in other portions of the display.
    Type: Grant
    Filed: September 6, 2016
    Date of Patent: December 18, 2018
    Assignee: Apple Inc.
    Inventors: Koorosh Aflatooni, Minhyuk Choi, Mohammad Ali Jangda, Sang Y. Youn, Yafei Bi, Jean-Pierre Guillou, Wei Y. Yao
  • Publication number: 20180322823
    Abstract: Systems and methods for improving perceived image quality of an electronic display communicatively coupled to an image data source that outputs a synchronization control signal, which indicates when an image frame is expected to stop being written, based on a source clock signal. The electronic display includes a display pixel row, a display driver, and a timing controller. The timing controller determines a target scan time to be used to write the image frame to the display pixel row and instructs the display driver to write the image frame to the display pixel row based on the target scan time and a display block signal, in which the timing controller instructs the display driver to continue writing the image frame to display pixel row after the electronic display receives the synchronization control signal when the synchronization control signal is received before the target scan time is reached.
    Type: Application
    Filed: September 21, 2017
    Publication date: November 8, 2018
    Inventors: Sinan Alousi, Haifeng Li, Mohammad Hajirostam, Yafei Bi
  • Patent number: 10096284
    Abstract: An electronic device includes a display panel. The display panel includes a number of pixels, each of which includes a driving thin-film-transistor (TFT) and a light-emitting diode. Compensation circuitry external to the display panel applies offset data to pixel data for each pixel of the plurality of pixels before the pixel data is provided to the plurality of pixels.
    Type: Grant
    Filed: September 20, 2016
    Date of Patent: October 9, 2018
    Assignee: Apple Inc.
    Inventors: Mohammad B. Vahid Far, Jesse A. Richmond, Yafei Bi
  • Patent number: 10089931
    Abstract: An electronic device that includes a display is provided. The display may have a brightness that is controlled using a series of cascaded digital-to-analog converter circuits. The display may be calibrated at a series of predetermined display brightness settings. For display brightness settings that fall between two consecutive display brightness settings in the series of predetermined display brightness settings, voltage interpolation operations may be performed to obtain the corresponding display brightness settings. Performing voltage interpolations instead of digital brightness setting interpolation helps minimize luminance jumps and unexpected color shifts when adjusting the brightness of the display.
    Type: Grant
    Filed: January 7, 2016
    Date of Patent: October 2, 2018
    Assignee: Apple Inc.
    Inventors: Koorosh Aflatooni, Yafei Bi, Hung Sheng Lin, Mohammad Ali Jangda
  • Patent number: 10089959
    Abstract: A display may have an array of display pixels. Digital display data may be received by a digital-to-analog converter that converts the digital display data to analog display data. The magnitudes of the analog display data signals can be controlled by a regulated voltage received by the digital-to-analog converter. A brightness controller may have multiple peak luminance control (PLC) profiles. In accordance with an embodiment, a brightness setting may be processed by a lookup table to identify a pair of PLC profiles that is interpolated in order to obtain the desired regulated voltage. In accordance with another embodiment, a single PLC profile may be used that is a function of a combined parameter that takes into account both average frame luminance and the brightness setting. In accordance with yet another embodiment, a lookup table that specifies brightness setting offset values may be used to directly modulate the brightness setting.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: October 2, 2018
    Assignee: Apple Inc.
    Inventors: Mohammad Ali Jangda, Koorosh Aflatooni, Yafei Bi
  • Publication number: 20180247586
    Abstract: Systems and apparatuses for hybrid micro-driver architectures having time multiplexing for driving displays are described. In one embodiment, a display (e.g., hybrid display architecture) includes a backplane and a micro-driver circuitry that is coupled to the backplane. The backplane includes circuitry (e.g., sample and hold circuitry) for sampling and holding analog data and for time multiplexing analog data. The micro-driver circuitry includes at least a capacitor of a ramp generator for generating a ramp voltage based on the analog data of the backplane and drive circuitry to cause at least one emission pulse for emitting a display element.
    Type: Application
    Filed: September 21, 2016
    Publication date: August 30, 2018
    Inventors: Mohammad B. Vahid Far, Yafei Bi, Kapil V. Sakariya, Hopil Bae, Shinya Ono, Thomas Charisoulis, Chin-Wei Lin
  • Patent number: 10042459
    Abstract: The disclosed embodiments relate to a system that provides power for a touch-enabled display, wherein the touch-enabled display cycles between a display mode and a touch mode. During the display mode, the system drives a display-mode voltage to the touch-enabled display through a power output, wherein the power output is coupled through a display-mode capacitor CD to ground. Next, during a transition from the display mode to the touch mode, the system couples the power output through a touch-mode capacitor CT to ground, wherein CT was previously charged to a touch-mode voltage, which causes the power output to rapidly transition to the touch-mode voltage. Then, during the touch mode, the system drives the touch-mode voltage through the power output.
    Type: Grant
    Filed: September 8, 2015
    Date of Patent: August 7, 2018
    Assignee: Apple Inc.
    Inventors: Christoph H. Krah, Yafei Bi, Kevin J. White
  • Patent number: 10019968
    Abstract: Systems and methods for synchronizing a video source and display circuitry using a dynamic tearing effect (TE) signal are provided. In one embodiment, an electronic display device includes: variable refresh rate circuitry that, when no new frame data is provided to the electronic display device, extends a vertical blanking period and reduces a refresh rate of the electronic display device. A tearing effect signal is generated, which is selectively set to a first logical level at a first period of time and a second logical level at a second period of time. The tearing effect signal is provided to the host electronic device that provides frame data to the electronic display device and upon receipt of new frame data, an un-extended vertical blanking period is returned to and the frame data at the next frame boundary is displayed.
    Type: Grant
    Filed: September 20, 2016
    Date of Patent: July 10, 2018
    Assignee: APPLE INC.
    Inventors: Yafei Bi, Arthur L. Spence, Vanessa C. Heppolette, Eran Tamari, Josh P. DeCesare
  • Patent number: 10002570
    Abstract: Systems and method for improving display quality of an electronic display. In one embodiment the electronic display includes a first display pixel that facilitates displaying a first image frame using first amplified image data and facilitates displaying a second image frame using second amplified image data; a second display pixel that facilitates displaying the first image frame using third amplified image data; a first amplifier that operates in a first operational mode to generate the first amplified image data based on image data corresponding with the first image frame and operates in a second operational mode to generate the second amplified image data based on image data corresponding with the second image frame; and a second amplifier that operates in the second operational mode to generate the third amplified image data based on the image data corresponding with the first image frame.
    Type: Grant
    Filed: December 18, 2015
    Date of Patent: June 19, 2018
    Assignee: APPLE INC.
    Inventors: Chin-Wei Lin, Vasudha Gupta, Yafei Bi
  • Publication number: 20180158173
    Abstract: A display device may include a display having a pixels and a processor. The processor may receive image data, determine a digital offset value for a pixel based on a location of the pixel, such that the digital offset value compensates for one or more non-uniformity properties of the pixel. The processor may determine a scale factor associated with the pixel based on at least two of a luminance setting for the display, a driving mode of the display, and a gray level value for the pixel. The processor may then generate correction image data by applying the scale factor to the digital offset value, generate compensated image data based on the correction image data and the image data, and provide the compensated image data to the display.
    Type: Application
    Filed: September 21, 2017
    Publication date: June 7, 2018
    Inventors: Shengkui GAO, Hung Sheng LIN, Hyunsoo KIM, Hyunwoo NHO, Katherine W. SONG, Mohammad HAJIROSTAM, Myung-Je CHO, Rui ZHANG, Sang Y. YOUN, Wei H. YAO, Yafei BI
  • Publication number: 20180090042
    Abstract: Electronic displays, systems, and methods that perform display panel sensing are provided. An electronic device may include processing circuitry that generates image data based at least in part on display panel sensing feedback and an electronic display. The electronic display may display the image data on pixels coupled to one of several sense lines. There may be an odd number of sense lines with common electrical characteristics. The electronic display may obtain display panel sense feedback at least in part by differentially sensing each one of the sense lines with sense lines with common electrical characteristics with another one of the sense lines the common electrical characteristics.
    Type: Application
    Filed: September 1, 2017
    Publication date: March 29, 2018
    Inventors: Hung Sheng Lin, Hyunwoo Nho, Shengkui Gao, Jesse A. Richmond, Jie Won Ryu, Junhua Tan, Kingsuk Brahma, Mohammad B. Vahid Far, Sun-Il Chang, Yafei Bi
  • Publication number: 20180082621
    Abstract: Systems and methods are provided for differential sensing (DS), difference-differential sensing (DDS), correlated double sampling (CDS), and/or programmable capacitor matching to reduce display panel sensing noise. An electronic device may include one or more processors and an electronic display. The one or more processors may generate image data and adjust the image data based at least in part on display sensing feedback. The electronic display may employ sensing circuitry that obtains the display sensing feedback at least in part by applying test data to a pixel of a column of an active area of the display and differentially senses an electrical value of the pixel in comparison to a reference signal from a different column. This reference signal may provide a common mode noise reference, which is removed by the differential sensing and thereby enhances a quality of the sensed electrical value of the pixel.
    Type: Application
    Filed: September 7, 2017
    Publication date: March 22, 2018
    Inventors: Hung Sheng Lin, Shengkui Gao, Hyunwoo Nho, Chin-Wei Lin, Mohammad B. Vahid Far, Jie Won Ryu, Kingsuk Brahma, Junhua Tan, Sun-II Chang, Shinya Ono, Jesse A. Richmond, Yafei Bi, Derek K. Shaeffer
  • Publication number: 20180083648
    Abstract: A device includes a resistor string that includes a plurality resistors with voltage taps disposed therebetween. The device may select one particular voltage tap of the plurality of voltage taps based on received gray level data for a pixel of a display. The device also includes a first amplifier that may be coupled to a first terminal end of the resistor string. The device additionally includes a second amplifier that may be coupled to a second terminal end of the resistor string, wherein the plurality of voltage taps may each supply a tap voltage derived from a voltage between the first amplifier and the second amplifier, wherein any tap amplifier of the device coupled to a voltage tap of the plurality of voltage taps provides a reference voltage thereto.
    Type: Application
    Filed: September 6, 2017
    Publication date: March 22, 2018
    Inventors: Baris Cagdaser, Derek K. Shaeffer, Hopil Bae, Jesse Aaron Richmond, Jie Won Ryu, Kingsuk Brahma, Mohammad B. Vahid Far, Shingo Hatanaka, Yafei Bi, Yuichi Okuda
  • Publication number: 20180082638
    Abstract: A display device may include a plurality of pixels that display image data on a display, a digital-to-analog converter that outputs a voltage that corresponds to a luminance value to be depicted on a first pixel, and a circuit that amplifies the voltage and outputs an amplified voltage to the first pixel. The circuit may include a capacitor that receives the voltage via the digital-to-analog converter and an amplifier coupled to the capacitor. The amplifier generates the amplified voltage based on the voltage stored the capacitor. The circuit also include switches that couple a first terminal of the capacitor to an output of the amplifier during a first amount of time and couples a second terminal of the capacitor to the output of the amplifier after the first amount of time expires.
    Type: Application
    Filed: September 6, 2017
    Publication date: March 22, 2018
    Inventors: Derek K. Shaeffer, Jesse A. Richmond, Kenichi Ueno, Kingsuk Brahma, Mohammad B. Vahid Far, Shingo Hatanaka, Yafei Bi
  • Publication number: 20180082620
    Abstract: Electronic devices and methods pertain to reducing artifacts resulting from a thermal profile preexisting a boot up of an electronic device are disclosed. Scanning driving circuitry of the electronic device scans at least a portion of one or more pixels of an active area of a display using a boot up scan before a boot up sequence of at least a portion of an electronic device completes. The results of the boot up scan are stored in local buffers and transferred to one or more processors upon connection to the one or more processors. The results of the boot up scan cause the one or more processors to modify image data to reduce or eliminate artifacts that may result during boot up due to thermal profiles or other parameters that may cause artifacts.
    Type: Application
    Filed: September 6, 2017
    Publication date: March 22, 2018
    Inventors: Sun-Il Chang, Hyunwoo Nho, Hung Sheng Lin, Junhua Tan, Jie Won Ryu, Kingsuk Brahma, Jesse A. Richmond, Mohammad B. Vahid Far, Yafei Bi