Patents by Inventor Liping Ma

Liping Ma 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: 8426040
    Abstract: Compounds including optionally substituted Ring Systems 1-4 are described. These compounds may be used as hosts in light-emitting devices. A light-emitting device comprising a compound selected from optionally substituted Ring Systems 1-4 is also described.
    Type: Grant
    Filed: February 23, 2011
    Date of Patent: April 23, 2013
    Assignee: Nitto Denko Corporation
    Inventors: Shijun Zheng, Liping Ma, Amane Mochizuki
  • Publication number: 20130069044
    Abstract: Generally, the devices provided herein comprise at least a hole-transport layer, two light-emitting layers, and an electron-transport layer, each having a highest occupied molecular orbital (HOMO) energy level and a lowest unoccupied molecular orbital (LUMO) energy level, wherein at least one of the HOMO energy levels and/or the LUMO energy levels of at least one of the light-emitting layers does not decrease in a stepwise fashion.
    Type: Application
    Filed: February 1, 2011
    Publication date: March 21, 2013
    Applicant: NITTO DENKO CORPORATION
    Inventor: Liping Ma
  • Publication number: 20120223635
    Abstract: Some porous films, such as organic non-polymeric porous films, may be useful for light outcoupling to increase light-emitting device efficiency. They may also be used for light scattering in other devices and for other applications related to the transfer of light.
    Type: Application
    Filed: March 2, 2012
    Publication date: September 6, 2012
    Applicant: NITTO DENKO CORPORATION
    Inventors: Amane Mochizuki, Liping Ma, Shijun Zheng, Sazzadur Rahman Khan, Sheng Li, Qianxi Lai, David T. Sisk, Brett Harding
  • Publication number: 20120197179
    Abstract: Methods and devices related to the treatment of diseases using phototherapy are described. Some embodiments provide an organic light-emitting diode device, such as a light-emitting device for phototherapy, comprising Ring system 1, Ring system 2, Ring system 3, or Ring system 4. Methods of treating disease with phototherapy are also described.
    Type: Application
    Filed: January 26, 2012
    Publication date: August 2, 2012
    Applicant: NITTO DENKO CORPORATION
    Inventors: Sazzadur Rahman Khan, Shijun Zheng, Amane Mochizuki, Liping Ma
  • Publication number: 20120121267
    Abstract: Embodiments of the present invention provide an Optical Add-Drop Multiplexer (OADM) Branching Unit (BU) and the corresponding optical transmission method and system.
    Type: Application
    Filed: January 20, 2012
    Publication date: May 17, 2012
    Applicant: HUAWEI MARINE NETWORKS CO., LTD.
    Inventors: Guozhong WANG, Liping MA, Ye WEN
  • Publication number: 20120121933
    Abstract: Emissive constructs having three emissive layers, each having the same fluorescent host are described. At least one of the layers further includes a phosphorescent dopant. Light-emitting devices including these emissive constructs are also described.
    Type: Application
    Filed: November 10, 2011
    Publication date: May 17, 2012
    Applicant: NITTO DENKO CORPORATION
    Inventors: Liping Ma, Shijun Zheng, Qianxi Lai, Amane Mochizuki
  • Publication number: 20110140093
    Abstract: Compounds including optionally substituted Ring Systems 1-4 may be used as hosts in light-emitting devices.
    Type: Application
    Filed: February 23, 2011
    Publication date: June 16, 2011
    Inventors: Shijun Zheng, Liping Ma, Amane Mochizuki
  • Publication number: 20110062386
    Abstract: Disclosed herein are compounds represented by a formula: Wherein Ar1, Cb, Ph1, Het1, and A are described herein. Compositions and light-emitting devices related thereto are also disclosed.
    Type: Application
    Filed: September 15, 2010
    Publication date: March 17, 2011
    Applicant: NITTO DENKO CORPORATION
    Inventors: Shijun Zheng, David T. Sisk, Brett T. Harding, Jensen Cayas, Sheng Li, Amane Mochizuki, Hyunsik Chae, Sazzadur Rahman Khan, Liping Ma, Rebecca Bottger
  • Patent number: 7544966
    Abstract: A three terminal electrical bistable device that includes a tri-layer composed of an electrically conductive mixed layer sandwiched between two layers of low conductivity organic material that is interposed between a top electrode and a bottom electrode. The conducting mixed layer serves as the middle electrode. The device includes two memory cells composed of electrode/organic layer/mixed layer, where the interfaces between the electrically conductive mixed layer and the low conductivity organic layer exhibit bistable behavior.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: June 9, 2009
    Assignee: The Regents of the University of California
    Inventors: Yang Yang, Liping Ma, Jun He
  • Patent number: 7482621
    Abstract: A bistable electrical device that is convertible between a low resistance state and a high resistance state. The device includes at least one layer of organic low conductivity material that is sandwiched between two electrodes. A buffer layer is located between the organic layer and at least one of the electrodes. The buffer layer includes particles in the form of flakes or dots of a low conducting material or insulating material that are present in a sufficient amount to only partially cover the electrode surface. The presence of the buffer layer controls metal migration into the organic layer when voltage pulses are applied between the electrodes to convert the device back and forth between the low and high resistance states.
    Type: Grant
    Filed: February 2, 2004
    Date of Patent: January 27, 2009
    Assignee: The Regents of the University of California
    Inventors: Yang Yang, Liping Ma
  • Patent number: 7476893
    Abstract: A vertical organic field effect transistor that includes an active cell and a capacitor that share a common source electrode. The active cell includes a semiconductor layer that is sandwiched between a drain electrode and the common source electrode. The capacitor includes a dielectric layer that is sandwiched between a gate electrode and the common source electrode. The common source electrode allows control of electrical current between the source and drain electrodes by controlling the electrical potential that is applied to the gate electrode.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: January 13, 2009
    Assignee: The Regents of the University of California
    Inventors: Yang Yang, Liping Ma
  • Publication number: 20070252126
    Abstract: An electroluminescent device based on bistability, and method for its use. The device alternates between a low resistance state and a high resistance state by application of an electrical voltage. A bistable electrical device has two electrodes sandwiching an organic material that produces bistable action. An organic light emitting diode next to the bistable device is emits light when conducting. To achieve graduated light output, circuitry is provided for applying to the bistable device a constant bias voltage intermediate a turnoff voltage and a turn-on voltage, and electrical pulses variable in a temporal pulse width or in an additional voltage, or in both. The additional voltage is superimposed on the bias voltage while the pulse is applied. The current through the bistable device, and therefore the brightness of light emitted by the diode after the pulse has ceased, are controlled by varying the pulse width or the additional voltage.
    Type: Application
    Filed: March 15, 2005
    Publication date: November 1, 2007
    Inventors: Haruo Kawakami, Yang Yang, Liping Ma
  • Publication number: 20070164272
    Abstract: A three terminal electrical bistable device that includes a tri-layer composed of an electrically conductive mixed layer sandwiched between two layers of low conductivity organic material that is interposed between a top electrode and a bottom electrode. The conducting mixed layer serves as the middle electrode. The device includes two memory cells composed of electrode/organic layer/mixed layer, where the interfaces between the electrically conductive mixed layer and the low conductivity organic layer exhibit bistable behavior.
    Type: Application
    Filed: December 1, 2004
    Publication date: July 19, 2007
    Inventors: Yang Yang, Liping Ma, Jun He
  • Publication number: 20060284230
    Abstract: A vertical organic field effect transistor that includes an active cell and a capacitor that share a common source electrode. The active cell includes a semiconductor layer that is sandwiched between a drain electrode and the common source electrode. The capacitor includes a dielectric layer that is sandwiched between a gate electrode and the common source electrode. The common source electrode allows control of electrical current between the source and drain electrodes by controlling the electrical potential that is applied to the gate electrode.
    Type: Application
    Filed: August 24, 2004
    Publication date: December 21, 2006
    Applicant: THE REGENTS OF THE UNIVERSITY OF CALIFORNIA
    Inventors: Yang Yang, Liping Ma
  • Publication number: 20060131560
    Abstract: A bistable electrical device that is convertible between a low resistance state and a high resistance state. The device includes at least one layer of organic low conductivity material that is sandwiched between two electrodes. A buffer layer is located between the organic layer and at least one of the electrodes. The buffer layer includes particles in the form of flakes or dots of a low conducting material or insulating material that are present in a sufficient amount to only partially cover the electrode surface. The presence of the buffer layer controls metal migration into the organic layer when voltage pulses are applied between the electrodes to convert the device back and forth between the low and high resistance states.
    Type: Application
    Filed: February 2, 2004
    Publication date: June 22, 2006
    Applicant: The Regents of the University of California
    Inventors: Yang Yang, Liping Ma
  • Patent number: 6950331
    Abstract: A bistable electrical device (50) employing a bistable body (52) and a high conductivity material (54). A sufficient amount of high conductivity material (54) is included in the bistable body (52) to impart bistable between a low resistance state and a high resistance state by application of an electrical voltage (60).
    Type: Grant
    Filed: May 24, 2001
    Date of Patent: September 27, 2005
    Assignee: The Regents of the University of California
    Inventors: Yang Yang, Liping Ma, Jie Liu
  • Publication number: 20050003574
    Abstract: A high temperature thermal annealing process creates a low resistance contact between a metal material and an organic material of an organic semiconductor device, which improves the efficiency of carrier injection. The process forms ohmic contacts and Schottky contacts. Additionally, the process may cause metal ions or atoms to migrate or diffuse into the organic material, cause the organic material to crystallize, or both. The resulting organic semiconductor device has enhanced operating characteristics such as faster speeds of operation. Instead of using heat, the process may use other forms of energy, such as voltage, current, electromagnetic radiation energy for localized heating, infrared energy and ultraviolet energy. An example enhanced organic diode comprising aluminum, carbon C60, and copper is described, as well as example insulated gate field effect transistors.
    Type: Application
    Filed: July 1, 2004
    Publication date: January 6, 2005
    Inventors: Yang Yang, Liping Ma, Michael Beigel
  • Patent number: 6784017
    Abstract: A high temperature thermal annealing process creates a low resistance contact between a metal material and an organic material of an organic semiconductor device, which improves the efficiency of carrier injection. The process forms ohmic contacts and Schottky contacts. Additionally, the process may cause metal ions or atoms to migrate or diffuse into the organic material, cause the organic material to crystallize, or both. The resulting organic semiconductor device has enhanced operating characteristics such as faster speeds of operation. Instead of using heat, the process may use other forms of energy, such as voltage, current, electromagnetic radiation energy for localized heating, infrared energy and ultraviolet energy. An example enhanced organic diode comprising aluminum, carbon C60, and copper is described, as well as example insulated gate field effect transistors.
    Type: Grant
    Filed: August 12, 2002
    Date of Patent: August 31, 2004
    Assignee: Precision Dynamics Corporation
    Inventors: Yang Yang, Liping Ma, Michael L. Beigel
  • Publication number: 20040033641
    Abstract: A high temperature thermal annealing process creates a low resistance contact between a metal material and an organic material of an organic semiconductor device, which improves the efficiency of carrier injection. The process forms ohmic contacts and Schottky contacts. Additionally, the process may cause metal ions or atoms to migrate or diffuse into the organic material, cause the organic material to crystallize, or both. The resulting organic semiconductor device has enhanced operating characteristics such as faster speeds of operation. Instead of using heat, the process may use other forms of energy, such as voltage, current, electromagnetic radiation energy for localized heating, infrared energy and ultraviolet energy. An example enhanced organic diode comprising aluminum, carbon C60, and copper is described, as well as example insulated gate field effect transistors.
    Type: Application
    Filed: August 12, 2002
    Publication date: February 19, 2004
    Applicant: Precision Dynamics Corporation
    Inventors: Yang Yang, Liping Ma, Michael L. Beigel
  • Publication number: 20040027849
    Abstract: A bistable electrical device (50) employing a bistable body (52) and a high conductivity material (54). A sufficient amount of high conductivity material (54) is included in the bistable body (52) to impart bistable between a low resistance state and a high resistance state by application of an electrical voltage (60).
    Type: Application
    Filed: July 8, 2003
    Publication date: February 12, 2004
    Inventors: Yang Yang, Liping Ma, Jie Liu