Patents by Inventor Yaser Azizi

Yaser Azizi 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).

  • Publication number: 20180182293
    Abstract: A system for driving a display that includes a plurality of pixel circuits arranged in an array, each of the pixel circuits including a light emitting device and a driving transistor for conveying a driving current through the light emitting device. Methods of measuring characteristics of circuit elements of pixels sharing a monitor line include the control of biasing to selectively turn off circuit elements or render their response known while measuring other circuit elements of interest.
    Type: Application
    Filed: February 23, 2018
    Publication date: June 28, 2018
    Inventors: Gholamreza Chaji, Yaser Azizi
  • Publication number: 20180158415
    Abstract: What is disclosed are display systems and methods of compensation of images produced by active matrix light emitting diode device (AMOLED) and other emissive displays. Anomalies in luminance produced by pixel circuits due to hysteresis effects are corrected through in-pixel compensation and resetting of the driving transistor.
    Type: Application
    Filed: December 6, 2017
    Publication date: June 7, 2018
    Inventors: Gholamreza Chaji, Yaser Azizi
  • Publication number: 20180158411
    Abstract: The OLED voltage of a selected pixel is extracted from the pixel produced when the pixel is programmed so that the pixel current is a function of the OLED voltage. One method for extracting the OLED voltage is to first program the pixel in a way that the current is not a function of OLED voltage, and then in a way that the current is a function of OLED voltage. During the latter stage, the programming voltage is changed so that the pixel current is the same as the pixel current when the pixel was programmed in a way that the current was not a function of OLED voltage. The difference in the two programming voltages is then used to extract the OLED voltage.
    Type: Application
    Filed: February 5, 2018
    Publication date: June 7, 2018
    Inventors: Yaser Azizi, Gholamreza Chaji
  • Publication number: 20180137821
    Abstract: A system for driving a display that includes a plurality of pixel circuits arranged in an array, each of the pixel circuits including a light emitting device and a driving transistor for conveying a driving current through the light emitting device. Each of a first plurality of supply lines is associated with at least one pixel circuit in a preselected segment of the array, the first plurality of supply lines providing driving currents to the at least one pixel circuit in the preselected segment. Each of a plurality of voltage supplies is configured to provide a supply voltage to the at least one pixel circuit in the preselected segment of the array, the voltage supplies being controllably coupled to the pixel circuits in the preselected segment of the array. A controller determines which of the plurality of voltage supplies to connect to the preselected segment of the array.
    Type: Application
    Filed: January 11, 2018
    Publication date: May 17, 2018
    Inventors: Yaser Azizi, Gholamreza Chaji
  • Patent number: 9940861
    Abstract: A method for characterizing and eliminating the effect of propagation delay on data and monitor lines of AMOLED panels is introduced. A similar technique may be utilized to cancel the effect of incomplete settling of select lines that control the write and read switches of pixels on a row.
    Type: Grant
    Filed: July 13, 2017
    Date of Patent: April 10, 2018
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Yaser Azizi
  • Patent number: 9934725
    Abstract: A system for driving a display that includes a plurality of pixel circuits arranged in an array, each of the pixel circuits including a light emitting device and a driving transistor for conveying a driving current through the light emitting device. Methods of measuring characteristics of circuit elements of pixels sharing a monitor line include the control of biasing to selectively turn off circuit elements or render their response known while measuring other circuit elements of interest.
    Type: Grant
    Filed: June 28, 2017
    Date of Patent: April 3, 2018
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Yaser Azizi
  • Patent number: 9922596
    Abstract: The OLED voltage of a selected pixel is extracted from the pixel produced when the pixel is programmed so that the pixel current is a function of the OLED voltage. One method for extracting the OLED voltage is to first program the pixel in a way that the current is not a function of OLED voltage, and then in a way that the current is a function of OLED voltage. During the latter stage, the programming voltage is changed so that the pixel current is the same as the pixel current when the pixel was programmed in a way that the current was not a function of OLED voltage. The difference in the two programming voltages is then used to extract the OLED voltage.
    Type: Grant
    Filed: April 24, 2017
    Date of Patent: March 20, 2018
    Assignee: Ignis Innovation Inc.
    Inventors: Yaser Azizi, Gholamreza Chaji
  • Publication number: 20180068611
    Abstract: What is disclosed are systems and methods of compensation of images produced by active matrix light emitting diode device (AMOLED) and other emissive displays. Anomalies in luminance produced by pixel circuits and bias currents produced by current biasing circuits for driving current biased voltage programmed pixels are corrected through calibration and compensation while re-using existing data or other lines that can be controlled individually to perform said calibration and compensation.
    Type: Application
    Filed: October 30, 2017
    Publication date: March 8, 2018
    Inventors: Gholamreza Chaji, Yaser Azizi, Arash Moradi, Hongxin Liu
  • Patent number: 9886899
    Abstract: A system for driving a display that includes a plurality of pixel circuits arranged in an array, each of the pixel circuits including a light emitting device and a driving transistor for conveying a driving current through the light emitting device. Each of a first plurality of supply lines is associated with at least one pixel circuit in a preselected segment of the array, the first plurality of supply lines providing driving currents to the at least one pixel circuit in the preselected segment. Each of a plurality of voltage supplies is configured to provide a supply voltage to the at least one pixel circuit in the preselected segment of the array, the voltage supplies being controllably coupled to the pixel circuits in the preselected segment of the array. A controller determines which of the plurality of voltage supplies to connect to the preselected segment of the array.
    Type: Grant
    Filed: September 19, 2014
    Date of Patent: February 6, 2018
    Assignee: Ignis Innovation Inc.
    Inventors: Yaser Azizi, Gholamreza Chaji
  • Publication number: 20180033368
    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: Application
    Filed: October 12, 2017
    Publication date: February 1, 2018
    Inventors: Gholamreza Chaji, Yaser Azizi, Maran Ran Ma, Arokia Nathan
  • Patent number: 9881587
    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. The present disclosure provides driving schemes for decreasing flickering perceived while displaying video content by introducing idle phases in between in emission phases to increase the effective refresh rate of a display. Driving schemes are also disclosed for reducing the effects of cross-talk by ensuring that programming information is refreshed in a display array that utilizes a driver connected to multiple data lines via a multiplexer.
    Type: Grant
    Filed: May 26, 2012
    Date of Patent: January 30, 2018
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Jackson Chi Sun Lai, Yaser Azizi, Maran Ran Ma
  • Publication number: 20180005557
    Abstract: Methods and systems to provide baseline measurements for aging compensation for a display device are disclosed. An example display system has a plurality of active pixels and a reference pixel. Common input signals are provided to the reference pixel and the plurality of active pixels. The outputs of the reference pixel is measured and compared to the output of the active pixels to determine aging effects. The display system may also be tested applying a first known reference current to a current comparator with a second variable reference current and the output of a device under test such as one of the pixels. The variable reference current is adjusted until the second current and the output of the device under test is equivalent of the first current. The resulting current of the device under test is stored in a look up table for a baseline for aging measurements during the display system operation.
    Type: Application
    Filed: September 13, 2017
    Publication date: January 4, 2018
    Inventors: Gholamreza Chaji, Joseph Marcel Dionne, Yaser Azizi, Javid Jaffari, Abbas Hormati, Tong Liu, Stefan Alexander
  • Publication number: 20180005558
    Abstract: A system reads a desired circuit parameter from a pixel circuit that includes a light emitting device, a drive device to provide a programmable drive current to the light emitting device, a programming input, and a storage device to store a programming signal. One embodiment of the extraction system turns off the drive device and supplies a predetermined voltage from an external source to the light emitting device, discharges the light emitting device until the light emitting device turns off, and then reads the voltage on the light emitting device while that device is turned off. The voltages on the light emitting devices in a plurality of pixel circuits may be read via the same external line, at different times.
    Type: Application
    Filed: September 14, 2017
    Publication date: January 4, 2018
    Inventors: Gholamreza Chaji, Ricky Yik Hei Ngan, Nino Zahirovic, Yaser Azizi
  • Publication number: 20180005559
    Abstract: Disclosed is a system and method to improve the extraction of transistor and OLED parameters in an AMOLED display for compensation of programming voltages to improve image quality. A pixel circuit includes an organic light emitting device, a drive device to provide a programmable drive current to the light emitting device, a programming input to provide the programming signal, and a storage device to store the programming signal. A charge-pump amplifier has a current input and a voltage output. The charge-pump amplifier includes an operational amplifier in negative feedback configuration. The feedback is provided by a capacitor connected between the output and the inverting input of the operational amplifier. A common-mode voltage source drives the non-inverting input of the operational amplifier. An electronic switch is coupled across the capacitor to reset the capacitor.
    Type: Application
    Filed: September 19, 2017
    Publication date: January 4, 2018
    Inventors: Gholamreza Chaji, Yaser Azizi
  • 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
  • Publication number: 20170309210
    Abstract: A method for characterizing and eliminating the effect of propagation delay on data and monitor lines of AMOLED panels is introduced. A similar technique may be utilized to cancel the effect of incomplete settling of select lines that control the write and read switches of pixels on a row.
    Type: Application
    Filed: July 13, 2017
    Publication date: October 26, 2017
    Inventors: Gholamreza Chaji, Yaser Azizi
  • Patent number: 9799246
    Abstract: A system reads a desired circuit parameter from a pixel circuit that includes a light emitting device, a drive device to provide a programmable drive current to the light emitting device, a programming input, and a storage device to store a programming signal. One embodiment of the extraction system turns off the drive device and supplies a predetermined voltage from an external source to the light emitting device, discharges the light emitting device until the light emitting device turns off, and then reads the voltage on the light emitting device while that device is turned off. The voltages on the light emitting devices in a plurality of pixel circuits may be read via the same external line, at different times.
    Type: Grant
    Filed: December 2, 2013
    Date of Patent: October 24, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Ricky Yik Hei Ngan, Nino Zahirovic, Yaser Azizi
  • Patent number: 9799248
    Abstract: A system to improve the extraction of transistor and OLED parameters in an AMOLED display includes a pixel circuit having an organic light emitting device, a drive device to provide a programmable drive current to the light emitting device, a programming input to provide the programming signal, and a storage device to store the programming signal. A charge-pump amplifier has a current input and a voltage output. The charge-pump amplifier includes an operational amplifier in negative feedback configuration. The feedback is provided by a capacitor connected between the output and the inverting input of the operational amplifier. A common-mode voltage source drives the non-inverting input of the operational amplifier. An electronic switch is coupled across the capacitor to reset the capacitor. A switch module including the input is coupled to the output of the pixel circuit and an output is coupled to the input of the charge-pump amplifier.
    Type: Grant
    Filed: January 31, 2017
    Date of Patent: October 24, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Yaser Azizi
  • Publication number: 20170301292
    Abstract: A system for driving a display that includes a plurality of pixel circuits arranged in an array, each of the pixel circuits including a light emitting device and a driving transistor for conveying a driving current through the light emitting device. Methods of measuring characteristics of circuit elements of pixels sharing a monitor line include the control of biasing to selectively turn off circuit elements or render their response known while measuring other circuit elements of interest.
    Type: Application
    Filed: June 28, 2017
    Publication date: October 19, 2017
    Inventors: Gholamreza Chaji, Yaser Azizi
  • Patent number: 9786209
    Abstract: Methods and systems to provide baseline measurements for aging compensation for a display device are disclosed. An example display system has a plurality of active pixels and a reference pixel. Common input signals are provided to the reference pixel and the plurality of active pixels. The outputs of the reference pixel is measured and compared to the output of the active pixels to determine aging effects. The display system may also be tested applying a first known reference current to a current comparator with a second variable reference current and the output of a device under test such as one of the pixels. The variable reference current is adjusted until the second current and the output of the device under test is equivalent of the first current. The resulting current of the device under test is stored in a look up table for a baseline for aging measurements during the display system operation.
    Type: Grant
    Filed: September 5, 2014
    Date of Patent: October 10, 2017
    Assignee: Ignis Innovation Inc.
    Inventors: Gholamreza Chaji, Joseph Marcel Dionne, Yaser Azizi, Javid Jaffari, Abbas Hormati, Tong Liu, Stefan Alexander