Patents by Inventor Arokia Nathan

Arokia Nathan 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: 9842544
    Abstract: A method and system for operating a pixel array having at least one pixel circuit is provided. The method includes repeating an operation cycle defining a frame period for a pixel circuit, including at each frame period, programming the pixel circuit, driving the pixel circuit, and relaxing a stress effect on the pixel circuit, prior to a next frame period. The system includes a pixel array including a plurality of pixel circuits and a plurality of lines for operation of the plurality of pixel circuits. Each of the pixel circuits includes a light emitting device, a storage capacitor, and a drive circuit connected to the light emitting device and the storage capacitor. The system includes a drive for operating the plurality of lines to repeat an operation cycle having a frame period so that each of the operation cycle comprises a programming cycle, a driving cycle and a relaxing cycle for relaxing a stress on a pixel circuit, prior to a next frame period.
    Type: Grant
    Filed: March 17, 2017
    Date of Patent: December 12, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Patent number: 9824632
    Abstract: Circuits for programming a circuit with decreased programming time are provided. Such circuits include a storage device such as a capacitor for storing display information and for ensuring a driving device such as a driving transistor drives a light emitting device according to the display information. To increase programming time, the pixel circuits may be pre-charged or a biasing current may be applied to charge and/or discharge a data line and/or the driving device. Aspects of the present disclosure allow for the biasing current to drain partially through the storage device to allow the portion of the biasing current applied to the driving device to remain small while the data line discharges. Furthermore, the present disclosure provides display architectures and operation schemes for display arranged in segments each including a plurality of pixel circuits.
    Type: Grant
    Filed: May 16, 2016
    Date of Patent: November 21, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Yaser Azizi, Maran Ran Ma, Arokia Nathan
  • Patent number: 9818376
    Abstract: A technique for improving the spatial and/or temporal uniformity of a light-emitting display by providing a faster calibration of reference current sources and reducing the noise effect by improving the dynamic range, despite instability and non-uniformity of the transistor devices. A calibration circuit for a display panel having an active area having a plurality of light emitting devices arranged on a substrate, and a peripheral area of the display panel separate from the active area is provided. The calibration circuit includes a first row of calibration current source or sink circuits and a second row of calibration current source or sink circuits. A first calibration control line is configured to cause the first row of calibration current source or sink circuits to calibrate the display panel with a bias current while the second row of calibration current source or sink circuits is being calibrated by a reference current.
    Type: Grant
    Filed: April 29, 2015
    Date of Patent: November 14, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Arokia Nathan
  • Patent number: 9805653
    Abstract: A method and system for driving a light emitting device display is provided. The system provides a timing schedule which increases accuracy in the display. The system may provide the timing schedule by which an operation cycle is implemented consecutively in a group of rows. The system may provide the timing schedule by which an aging factor is used for a plurality of frames.
    Type: Grant
    Filed: April 5, 2016
    Date of Patent: October 31, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Patent number: 9792857
    Abstract: Raw grayscale image data, representing images to be displayed in successive frames, is used to drive a display having pixels that include a drive transistor and an organic light emitting device by dividing each frame into at least first and second-frames, and supplying each pixel with a drive current that is higher in the first sub-frame than in the second sub-frame for raw grayscale values in a first preselected range, and higher in the second sub-frame than in the first sub-frame for raw grayscale values in a second preselected range. The display may be an active matrix display, such as an AMOLED display.
    Type: Grant
    Filed: April 15, 2016
    Date of Patent: October 17, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Kongning Li, Vasudha Gupta, Gholamreza Chaji, Arokia Nathan
  • Patent number: 9773441
    Abstract: A system and method for determining and applying characterization correlation curves for aging effects on an organic light organic light emitting device (OLED) based pixel is disclosed. A first stress condition is applied to a reference pixel having a drive transistor and an OLED. An output voltage based on a reference current is measured periodically to determine an electrical characteristic of the reference pixel under the first predetermined stress condition. The luminance of the reference pixel is measured periodically to determine an optical characteristic of the reference pixel. A characterization correlation curve corresponding to the first stress condition including the determined electrical and optical characteristic of the reference pixel is stored. The stress condition of an active pixel is determined and a compensation voltage is determined by correlating the stress condition of the active pixel with curves of the predetermined stress conditions.
    Type: Grant
    Filed: July 29, 2016
    Date of Patent: September 26, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Javid Jaffari, Arokia Nathan
  • Publication number: 20170262099
    Abstract: A device (48) for combined capacitance and pressure measurements includes a number of first input/output terminals for a projected capacitance touch panel wherein the projected capacitance touch panel includes a layer of piezoelectric material disposed between a plurality of first electrodes and at least one second electrode. The device also includes a plurality of second input/output terminals for a capacitive touch controller. The device also includes a plurality of separation stages, each separation stage connecting at least one first input/output terminal to a corresponding second input/output terminal, and each separation stage including a first frequency-dependent filter for filtering signals between first and second input/output terminals.
    Type: Application
    Filed: May 16, 2017
    Publication date: September 14, 2017
    Inventors: Arokia Nathan, Simon Banks
  • Patent number: 9741292
    Abstract: Method and system for programming and driving active matrix light emitting device pixel is provided. The pixel is a voltage programmed pixel circuit, and has a light emitting device, a driving transistor and a storage capacitor. The pixel has a programming cycle having a plurality of operating cycles, and a driving cycle. During the programming cycle, the voltage of the connection between the OLED and the driving transistor is controlled so that the desired gate-source voltage of a driving transistor is stored in a storage capacitor.
    Type: Grant
    Filed: September 2, 2015
    Date of Patent: August 22, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Gholamreza Chaji, Peyman Servati
  • Publication number: 20170228096
    Abstract: A method for processing signals from a touchscreen panel includes obtaining a partial frame by sampling parts of a frame from a touch panel which comprises an array of sensor areas (step S1). The method also includes generating, based on the partial frame, a new frame which comprises estimates of the un-sampled parts (step S2). The method also includes determining whether at least one touch event is present in the new frame (step S3), and upon a positive determination, for each touch event, determining a location of the touch event in the new frame and obtaining a sub-frame by sampling a region of a subsequent frame from the touch panel frame at and around the location (step S4). The method also includes outputting touch information based on one or more sub-frames (step S7).
    Type: Application
    Filed: February 1, 2017
    Publication date: August 10, 2017
    Inventors: Arokia Nathan, Jackson Lai, Shuo Gao
  • Patent number: 9728135
    Abstract: A voltage programmed pixel circuit, display system having the pixel circuit and driving method thereof is provided. The pixel circuit includes a light emitting device, a driving transistor connected to the light emitting device and a programming circuit. The programming circuit adjusts a pixel current during a programming cycle of the pixel circuit.
    Type: Grant
    Filed: May 23, 2016
    Date of Patent: August 8, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Gholamreza Chaji, Peyman Servati
  • Publication number: 20170199624
    Abstract: A device for combined capacitance and pressure measurements includes a plurality of first input/output terminals for a projected capacitance touch panel wherein the projected capacitance touch panel includes a layer of piezoelectric material disposed between a plurality of sensing electrodes and a common electrode. The device also includes a plurality of second input/output terminals for a capacitive touch controller. The device also includes a plurality of separation stages, each separation stage connecting one first input/output terminal to a corresponding second input/output terminal, and each separation stage includes a first frequency-dependent filter for filtering signals between respective first and second input/output terminals.
    Type: Application
    Filed: December 21, 2016
    Publication date: July 13, 2017
    Inventors: Arokia Nathan, Simon Banks
  • Publication number: 20170193915
    Abstract: A method and system for operating a pixel array having at least one pixel circuit is provided. The method includes repeating an operation cycle defining a frame period for a pixel circuit, including at each frame period, programming the pixel circuit, driving the pixel circuit, and relaxing a stress effect on the pixel circuit, prior to a next frame period. The system includes a pixel array including a plurality of pixel circuits and a plurality of lines for operation of the plurality of pixel circuits. Each of the pixel circuits includes a light emitting device, a storage capacitor, and a drive circuit connected to the light emitting device and the storage capacitor. The system includes a drive for operating the plurality of lines to repeat an operation cycle having a frame period so that each of the operation cycle comprises a programming cycle, a driving cycle and a relaxing cycle for relaxing a stress on a pixel circuit, prior to a next frame period.
    Type: Application
    Filed: March 17, 2017
    Publication date: July 6, 2017
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Publication number: 20170139527
    Abstract: A method is described including receiving (S3) a first array of values obtained from measuring an array of touch panel sensor areas (FIG. 4; In,m). The method also includes generating (S4) a second array of values based on subtracting a reference array of values from the first array of values. The method also includes determining (S5) presence of at least one touch event in dependence upon the second array of value and, upon a negative determination (S8) generating a new reference array based on exponential smoothing of the reference array and the first array using a weighting factor, wherein the weighting factor is zero, and storing the new reference matrix and, upon a positive determination (S6) outputting the second array (FIG. 9).
    Type: Application
    Filed: November 8, 2016
    Publication date: May 18, 2017
    Inventors: Arokia Nathan, Jackson Chi-Sun Lai, Gao Shuo
  • Publication number: 20170125498
    Abstract: A pixel having an organic light emitting diode (OLED) and method for fabricating the pixel is provided. A planarization dielectric layer is provided between a thin-film transistor (TFT) based backplane and OLED layers. A through via between the TFT backplane and the OLED layers forms a sidewall angle of less than 90 degrees to the TFT backplane. The via area and edges of an OLED bottom electrode pattern may be covered with a dielectric cap.
    Type: Application
    Filed: January 11, 2017
    Publication date: May 4, 2017
    Inventors: Denis Striakhilev, Arokia Nathan, Yuri Vygranenko, Sheng Tao
  • Patent number: 9633597
    Abstract: A method and system for operating a pixel array having at least one pixel circuit is provided. The method includes repeating an operation cycle defining a frame period for a pixel circuit, including at each frame period, programming the pixel circuit, driving the pixel circuit, and relaxing a stress effect on the pixel circuit, prior to a next frame period. The system includes a pixel array including a plurality of pixel circuits and a plurality of lines for operation of the plurality of pixel circuits. Each of the pixel circuits includes a light emitting device, a storage capacitor, and a drive circuit connected to the light emitting device and the storage capacitor. The system includes a drive for operating the plurality of lines to repeat an operation cycle having a frame period so that each of the operation cycle comprises a programming cycle, a driving cycle and a relaxing cycle for relaxing a stress on a pixel circuit, prior to a next frame period.
    Type: Grant
    Filed: April 28, 2014
    Date of Patent: April 25, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Publication number: 20170069266
    Abstract: A system and method are disclosed for determining a pixel capacitance. The pixel capacitance is correlated to a pixel age to determine a current correction factor used for compensating the pixel drive current to account for luminance degradation of the pixel that results from the pixel aging.
    Type: Application
    Filed: November 18, 2016
    Publication date: March 9, 2017
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Publication number: 20170025065
    Abstract: A method and system for driving an active matrix display is provided. The system includes a drive circuit for a pixel having a light emitting device. The drive circuit includes a drive transistor for driving the light emitting device. The system includes a mechanism for adjusting the gate voltage of the drive transistor.
    Type: Application
    Filed: October 7, 2016
    Publication date: January 26, 2017
    Inventors: Arokia Nathan, Gholamreza Chaji
  • Publication number: 20170011674
    Abstract: A system and method for determining and applying characterization correlation curves for aging effects on an organic light organic light emitting device (OLED) based pixel is disclosed. A first stress condition is applied to a reference pixel having a drive transistor and an OLED. An output voltage based on a reference current is measured periodically to determine an electrical characteristic of the reference pixel under the first predetermined stress condition. The luminance of the reference pixel is measured periodically to determine an optical characteristic of the reference pixel. A characterization correlation curve corresponding to the first stress condition including the determined electrical and optical characteristic of the reference pixel is stored. The stress condition of an active pixel is determined and a compensation voltage is determined by correlating the stress condition of the active pixel with curves of the predetermined stress conditions.
    Type: Application
    Filed: July 29, 2016
    Publication date: January 12, 2017
    Inventors: Gholamreza Chaji, Javid Jaffari, Arokia Nathan
  • Publication number: 20170004769
    Abstract: A technique for driving a column of pixels that include light emitting elements. The technique incorporates feedback data provided from feedback data sources connected to the data line and to feedback line of the array, pixel driving circuit with feedback path. The technique can also include block of the reference elements for input signal corrections.
    Type: Application
    Filed: September 15, 2016
    Publication date: January 5, 2017
    Inventors: Arokia Nathan, Yuriy Vygranenko, Shahin Jafarabadiashtiani, Peyman Servati
  • Patent number: RE46561
    Abstract: A display system includes a driver for operating a panel having a plurality of pixels arranged by a plurality of first lines and at least one second line The driver includes a driver output unit for providing to the panel a single driver output for activating the plurality of first lines, the single driver output being demultiplexed on the panel to activate each first line.
    Type: Grant
    Filed: September 4, 2014
    Date of Patent: September 26, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Kongning Li, Vasudha Gupta, Arokia Nathan