Patents by Inventor Wing Chiu Yip

Wing Chiu Yip 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: 8576485
    Abstract: A method of forming a polarizing material is provided including exposing a layer of dichroic material to activating light illumination to provide an ordered structure with a distinguished absorption axis and thus photo-induce polarization, and fixing the induced polarization by polymerization of the dichroic layer. Novel polarizing materials formed thereby are also provided. By selectively exposing regions of the dichroic material to differing activating radiation, different regions with different polarization axes can be created. The polarizing material can also be provided with a coating or coatings to alter the spectral responses, and a stack formed of a plurality if dichroic layers can be provided.
    Type: Grant
    Filed: September 28, 2010
    Date of Patent: November 5, 2013
    Assignee: The Hong Kong University of Science and Technology
    Inventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Hoi Sing Kwok
  • Patent number: 8508448
    Abstract: This invention provides a method and apparatus for driving bistable cholesteric liquid crystal displays. The method and apparatus provided a display in which all the pixels are initially driven to the P state. Selected pixels for the display are then driven to the FC state to provide the desired message. The state of the pixels is then maintained for a viewing period prior to any resetting of the display to the P state. The switching from the P state to the FC state allows fast addressing times and lower voltages to be used in driving the display.
    Type: Grant
    Filed: November 7, 2005
    Date of Patent: August 13, 2013
    Assignee: The Hong Kong University of Science and Technology
    Inventors: Hoi-Sing Kwok, Fei-Hong Yu, Qing-Cheng Li, Wing-Chiu Yip
  • Publication number: 20120307363
    Abstract: A method of forming a polarizing material is provided including exposing a layer of dichroic material to activating light illumination to provide an ordered structure with a distinguished absorption axis and thus photo-induce polarization, and fixing the induced polarization by polymerization of the dichroic layer. Novel polarizing materials formed thereby are also provided. By selectively exposing regions of the dichroic material to differing activating radiation, different regions with different polarization axes can be created. The polarizing material can also be provided with a coating or coatings to alter the spectral responses, and a stack formed of a plurality if dichroic layers can be provided.
    Type: Application
    Filed: September 28, 2010
    Publication date: December 6, 2012
    Applicant: The Hong Kong University of Science and Technology
    Inventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Elena Karlovna Prudnikova, Hoi Sing Kwok
  • Patent number: 7696971
    Abstract: The invention provides a method for controlling the grey-scale modulation of a reflective bistable cholesteric display by applying selected sequences of high and low pulses to modulate the cholesteric domain size and helical axis orientation. Non-mesogenic dopants may also be added to reduce the drive voltage.
    Type: Grant
    Filed: May 10, 2002
    Date of Patent: April 13, 2010
    Assignees: The Hong Kong University of Science and Technology
    Inventors: Wing Chiu Yip, Hoi Sing Kwok, Cheryl Sun
  • Patent number: 7381507
    Abstract: This invention relates to methods for preparing photo-patterned mono- or polychromatic, polarizing films. The polarizer can be pixelated into a number of small regions wherein some of the regions have one orientation of the principal neutral or color absorbing axis; and some other of the said regions have another orientation of the principal neutral or color absorbing axis. The axis orientation is determined by the polarization vector of actinic radiation and the multi-axes orientation is possible by a separated masked exposure. This polarizer can be placed on the interior substrate surface of the LCD cell.
    Type: Grant
    Filed: July 10, 2003
    Date of Patent: June 3, 2008
    Assignee: The Hong Kong University of Science and Technology
    Inventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov
  • Patent number: 7070913
    Abstract: The present invention provides a method of forming a polarizing material comprising exposing a layer of dichroic material to activating light illumination to provide an ordered structure with a distinguished absorption axis and thus photo-induce polarization, and fixing the induced polarization by polymerisation of the dichroic layer. The present invention also provides novel polarizing materials formed thereby. By selectively exposing regions of the dichroic material to differing activating radiation, different regions with different polarization axes can be created. The polarizing material can also be provided with a coating or coatings to alter the spectral response, and a stack formed of a plurality if dichroic layers may be provided.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: July 4, 2006
    Assignee: The Hong Kong University of Science and Technology
    Inventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Elena Karlovna Prudnikova, Hoi Sing Kwok
  • Publication number: 20060055650
    Abstract: This invention provides a method and apparatus for driving bistable cholesteric liquid crystal displays. The method and apparatus provided a display in which all the pixels are initially driven to the P state. Selected pixels for the display are then driven to the FC state to provide the desired message. The state of the pixels is then maintained for a viewing period prior to any resetting of the display to the P state. The switching from the P state to the FC state allows fast addressing times and lower voltages to be used in driving the display.
    Type: Application
    Filed: November 7, 2005
    Publication date: March 16, 2006
    Inventors: Hoi-Sing Kwok, Fei-Hong Yu, Qing-Cheng Li, Wing-Chiu Yip
  • Publication number: 20050024307
    Abstract: This invention provides a method and apparatus for driving bistable cholesteric liquid crystal displays. The method and apparatus provided a display in which all the pixels are initially driven to the P state. Selected pixels for the display are then driven to the FC state to provide the desired message. The state of the pixels is then maintained for a viewing period prior to any resetting of the display to the P state. The switching from the P state to the FC state allows faster addressing times and lower voltages to be used in driving the display.
    Type: Application
    Filed: June 30, 2004
    Publication date: February 3, 2005
    Applicant: The Hong Kong University of Science & Technology
    Inventors: Hoi-Sing Kwok, Fei-Hong Yu, Qing-Cheng Li, Wing-Chiu Yip
  • Publication number: 20040008298
    Abstract: This invention relates to methods for preparing photo-patterned mono- or polychromatic, polarizing films. The polarizer can be pixelated into a number of small regions wherein some of the regions have one orientation of the principal neutral or color absorbing axis; and some other of the said regions have another orientation of the principal neutral or color absorbing axis. The axis orientation is determined by the polarization vector of actinic radiation and the multi-axes orientation is possible by a separated masked exposure. This polarizer can be placed on the interior substrate surface of the LCD cell.
    Type: Application
    Filed: July 10, 2003
    Publication date: January 15, 2004
    Applicant: The Hong Kong University of Science and Technology
    Inventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov
  • Patent number: 6630289
    Abstract: This invention relates to methods for preparing photo-patterned mono- or polychromatic, polarizing films. The polarizer can be pixelated into a number of small regions wherein some of the regions have one orientation of the principal neutral or color absorbing axis; and some other of the said regions have another orientation of the principal neutral or color absorbing axis. The axis orientation is determined by the polarization vector of actinic radiation and the multi-axes orientation is possible by a separated masked exposure. This polarizer can be placed on the interior substrate surface of the LCD cell.
    Type: Grant
    Filed: August 22, 2000
    Date of Patent: October 7, 2003
    Assignee: The Hong Kong University of Science and Technology
    Inventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov
  • Publication number: 20030072896
    Abstract: The present invention relates to chemical compositions of synthetic dyes and a fabrication process for the photo-induced alignment of liquid crystals. The compositions and methods of the invention are applicable to lateral field driven LCDs such as the In-plane Switching mode. A method of alignment using a multiple wavelengths light source is disclosed. This is a non-contact technique to align liquid crystals so that the particulates and static charges generated by the rubbing process can be eliminated. A synthetic dye film is exposed to a linearly polarized or non-polarized light. Due to photoisomerization, conformational molecular change occurs, and the isomer orientation is no longer random but becomes anisotropic. This in turn gives rise to a homogeneous anisotropic orientation of the liquid crystal molecules.
    Type: Application
    Filed: June 7, 2002
    Publication date: April 17, 2003
    Applicant: The Hong Kong University of Science and Technology
    Inventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov, Elena Prudnikova
  • Publication number: 20020172893
    Abstract: The present invention provides a method of forming a polarizing material comprising exposing a layer of dichroic material to activating light illumination to provide an ordered structure with a distinguished absorption axis and thus photo-induce polarization, and fixing the induced polarization by polymerisation of the dichroic layer. The present invention also provides novel polarizing materials formed thereby. By selectively exposing regions of the dichroic material to differing activating radiation, different regions with different polarization axes can be created. The polarizing material can also be provided with a coating or coatings to alter the spectral response, and a stack formed of a plurality if dichroic layers may be provided.
    Type: Application
    Filed: May 14, 2001
    Publication date: November 21, 2002
    Inventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Elena Karlovna Prudnikova, Hoi Sing Kwok
  • Publication number: 20010015723
    Abstract: This invention provides a method and apparatus for driving bistable cholesteric liquid crystal displays. The method and apparatus provided a display in which all the pixels are initially driven to the P state. Selected pixels for the display are then driven to the FC state to provide the desired message. The state of the pixels is then maintained for a viewing period prior to any resetting of the display to the P state. The switching from the P state to the FC state allows faster addressing times and lower voltages to be used ha driving the display.
    Type: Application
    Filed: May 1, 1998
    Publication date: August 23, 2001
    Inventors: HOI-SING KWOK, FEI-HONG YU, QING-CHENG LI, WING CHIU YIP