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).
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Patent number: 8576485Abstract: 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: GrantFiled: September 28, 2010Date of Patent: November 5, 2013Assignee: The Hong Kong University of Science and TechnologyInventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Hoi Sing Kwok
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Patent number: 8508448Abstract: 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: GrantFiled: November 7, 2005Date of Patent: August 13, 2013Assignee: The Hong Kong University of Science and TechnologyInventors: Hoi-Sing Kwok, Fei-Hong Yu, Qing-Cheng Li, Wing-Chiu Yip
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Publication number: 20120307363Abstract: 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: ApplicationFiled: September 28, 2010Publication date: December 6, 2012Applicant: The Hong Kong University of Science and TechnologyInventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Elena Karlovna Prudnikova, Hoi Sing Kwok
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Patent number: 7696971Abstract: 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: GrantFiled: May 10, 2002Date of Patent: April 13, 2010Assignees: The Hong Kong University of Science and TechnologyInventors: Wing Chiu Yip, Hoi Sing Kwok, Cheryl Sun
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Patent number: 7381507Abstract: 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: GrantFiled: July 10, 2003Date of Patent: June 3, 2008Assignee: The Hong Kong University of Science and TechnologyInventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov
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Patent number: 7070913Abstract: 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: GrantFiled: May 14, 2001Date of Patent: July 4, 2006Assignee: The Hong Kong University of Science and TechnologyInventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Elena Karlovna Prudnikova, Hoi Sing Kwok
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Publication number: 20060055650Abstract: 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: ApplicationFiled: November 7, 2005Publication date: March 16, 2006Inventors: Hoi-Sing Kwok, Fei-Hong Yu, Qing-Cheng Li, Wing-Chiu Yip
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Publication number: 20050024307Abstract: 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: ApplicationFiled: June 30, 2004Publication date: February 3, 2005Applicant: The Hong Kong University of Science & TechnologyInventors: Hoi-Sing Kwok, Fei-Hong Yu, Qing-Cheng Li, Wing-Chiu Yip
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Publication number: 20040008298Abstract: 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: ApplicationFiled: July 10, 2003Publication date: January 15, 2004Applicant: The Hong Kong University of Science and TechnologyInventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov
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Patent number: 6630289Abstract: 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: GrantFiled: August 22, 2000Date of Patent: October 7, 2003Assignee: The Hong Kong University of Science and TechnologyInventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov
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Publication number: 20030072896Abstract: 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: ApplicationFiled: June 7, 2002Publication date: April 17, 2003Applicant: The Hong Kong University of Science and TechnologyInventors: Hoi-Sing Kwok, Wing-Chiu Yip, Vladimir Chigrinov, Vladimir Kozenkov, Elena Prudnikova
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Publication number: 20020172893Abstract: 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: ApplicationFiled: May 14, 2001Publication date: November 21, 2002Inventors: Vladimir Markovich Kozenkov, Wing Chiu Yip, Vladimir Grigorievich Chigrinov, Elena Karlovna Prudnikova, Hoi Sing Kwok
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Publication number: 20010015723Abstract: 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: ApplicationFiled: May 1, 1998Publication date: August 23, 2001Inventors: HOI-SING KWOK, FEI-HONG YU, QING-CHENG LI, WING CHIU YIP