Patents by Inventor Bao-Gang Wu

Bao-Gang Wu 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: 20080151199
    Abstract: A quasi-axial optical imagery projection system is disclosed in this paper. The system includes optical imagery sets; each may be lenses, mirrors, or a combination of both. The system also has a light source close to an imager, which may be a planar mask with a pattern, a LCD imager, or other suitable imagers. The system also has a display screen. Both the imager and the display screen are set at acute angles with respect to an optical axis so that what is projected on the display screen is a magnified image of the imager by a magnification factor that has a transverse component and a longitudinal component. This quasi-axial projection system may be made thinner than other rear projection system of comparable screen size.
    Type: Application
    Filed: December 21, 2006
    Publication date: June 26, 2008
    Inventors: Bao-gang Wu, Ji-ning Wu, Lu Cheng, Jian-mi Gao, Shuai Zeng, Hong-shou Yu, Yu-kuan Li, Wei Zhang, Zhi-jian Zhang, Shou-ying Liu, Qin Zhao
  • Publication number: 20030071958
    Abstract: A liquid crystal device for writing, inputting, and displaying information comprises: a first substrate, a second substrate, and a cell structure sandwiched between the two substrates, defining a plurality of isolated subcells. Means for applying an electric field to drive states of the cholesteric liquid crystal in the subcells is coupled to the electrodes. An electromagnetic sensitive panel is positioned proximately under the surface of the second substrate for receiving an electronic/magnetic signal transmitted by a writing tool. In use, when the tip of the writing tool is forced again and moved around the surface of the first substrate, a true track of the movement of the tip is directly shown on the writing surface, while information of the movement of the tip of the writing tool is sensed by the electromagnetic sensitive panel simultaneously.
    Type: Application
    Filed: October 12, 2001
    Publication date: April 17, 2003
    Inventors: Bao-Gang Wu, Shushan Li, Yong-Jing Wang, Jianmi Gao, Ruihai Sun, Yong Nam Kang, Ying Sun, Gang Chen
  • Publication number: 20020180913
    Abstract: Disclosed are various reverse-mode direct-view liquid crystal displays (LCD) employing a liquid crystal having a characteristic wavelength in the non-visible spectrum, including reflective and transflective mode displays, and methods of fabrication. In accordance with the principles disclosed, a reflectance mode direct-view LCD includes a polarizer, a reflector, and a cholesteric liquid crystal (CLC) packed between the polarizer and reflector and having a characteristic wavelength to reflect non-visible spectrum. Portions of the CLC can selectively exhibit a planar state or a focal-conic state, the portions of the CLC in the planar state appearing black, and the portions of the CLC in the focal-conic state appearing white to an observer of the LCD. A transflective mode LCD is derived by further combination of polarizers, transflective mirrors and internal light sources.
    Type: Application
    Filed: December 19, 2001
    Publication date: December 5, 2002
    Inventors: Bao-Gang Wu, Jianan Hou, Jianmi Gao, Yong-Jing Wang, Shushan Li, Ruihai Sun, Gang Chen
  • Publication number: 20020180914
    Abstract: Disclosed are various reverse-mode direct-view liquid crystal displays (LCD) employing a liquid crystal having a characteristic wavelength in the non-visible spectrum, including transmissive mode displays, and methods of fabrication. In accordance with the principles disclosed, a transmitance mode direct-view LCD includes a first linear polarizer, a second linear polarizer, an internal light source and a cholesteric liquid crystal (CLC) located between the first and second linear polarizers and having a characteristic wavelength to reflect in a non-visible region of light. Portions of the CLC can selectively exhibit a planar state or a focal-conic state, the portions of the CLC in the planar state appearing black, and the portions of the CLC in the focal-conic state appearing white to an observer of the LCD.
    Type: Application
    Filed: December 19, 2001
    Publication date: December 5, 2002
    Applicant: Display Research Incorporated
    Inventors: Bao-Gang Wu, Jianan Hou, Jianmi Gao, Yong-Jing Wang, Shushan Li, hai Sun, Gang Chen
  • Patent number: 6462805
    Abstract: Disclosed are various reverse-mode direct-view liquid crystal displays employing a liquid crystal having a characteristic wavelength in the non-visible spectrum, including reflective, transmissive and reflective-transmissive mode displays. In accordance with the principles disclosed, a direct-view liquid crystal display (LCD) includes a front substantially transparent substrate, a rear substrate, and a controllable cholesteric liquid crystal (CLC) disposed between the front and rear substrates and having a characteristic wavelength to reflect non-visible spectrum; the portions of the controllable CLC can selectively exhibit a planar state or a focal-conic state, the portions of the CLC in the planar state appearing dark, and the portions of the CLC in the focal-conic state appearing bright, to an observer of the LCD.
    Type: Grant
    Filed: June 4, 2001
    Date of Patent: October 8, 2002
    Assignee: Display Research, Inc.
    Inventors: Bao-Gang Wu, Jianan Hou, Jianmi Gao, Yong-Jing Wang, Shushan Li, Rui Hai Sun, Gang Chen
  • Patent number: 6285434
    Abstract: A substrate for a multi-color liquid crystal display (LCD), an LCD having the substrate, and methods of manufacturing the substrate and the LCD. In one embodiment, the substrate includes: (1) a substantially planar base and (2) a cell wall structure, located on a surface of the base, that defines at least first and second sets of independent cells having corresponding independent fluid fill ports when the cell wall structure is bonded to an opposing substrate.
    Type: Grant
    Filed: February 20, 1998
    Date of Patent: September 4, 2001
    Assignee: Advanced Display Systems, Inc.
    Inventors: Yao Dong Ma, Bao-Gang Wu, Jianmi Gao, Jianan Hou, Yong-Jing Wang, Qihui J. Zhang
  • Patent number: 5949513
    Abstract: Methods of manufacturing a liquid crystal display ("LCD"); specifically, a multi-color LCD, e.g., a red-green-blue ("RGB") LCD. The methods include the steps of: (1) depositing a twist agent on a first substrate, the twist agent becoming an in situ twist agent, (2) bringing a second substrate into proximity with the first substrate to form at least one interstitial region between the second and first substrates, (3) introducing liquid crystal ("LC") having an initial pitch into the at least one interstitial region proximate the in situ twist agent and (4) stimulating the LC and the in situ twist agent to cause the LC and the in situ twist agent to mix in situ, the in situ twist agent changing the initial pitch of the LC.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: September 7, 1999
    Assignee: Advanced Display System, Inc.
    Inventors: Yao-Dong Ma, Bao-Gang Wu
  • Patent number: 5933203
    Abstract: Driver apparatus and methods of driving at least a portion of a cholesteric liquid crystal ("CLC") panel to a state having a given reflectivity. One of the methods includes the steps of: (1) initially driving the portion to a nematic phase, (2) subsequently driving the portion to a cholesteric phase focal-conic state, the cholesteric phase focal-conic state providing a known reference state for subsequent driving of the portion and (3) thereafter driving the portion to the state having the given reflectivity.
    Type: Grant
    Filed: January 8, 1997
    Date of Patent: August 3, 1999
    Assignee: Advanced Display Systems, Inc.
    Inventors: Bao-Gang Wu, Jianmi Gao, Meng Zhao
  • Patent number: 5889566
    Abstract: A light modulating apparatus containing cholesteric liquid crystals capable of indefinite zero field retention of optical images, including full color and complete gray scale capability, is described. This invention is predicated on establishment of zero field multistable liquid crystal domains representing a continuous distribution of states ranging from the highly reflective planar to the light-scattering focal-conic structures. The zero field multistable domain structure stability is achieved by controlling solid surface-liquid crystal boundary interactions to provide essential equalization of the total system energy of each of the domain structures. This is the first time this equalization, and thus zero field multistability, has been achieved without the use of a polymer gel addition to create rigid polydomains in the liquid crystal mix.
    Type: Grant
    Filed: April 17, 1997
    Date of Patent: March 30, 1999
    Assignee: Advanced Display Systems, Inc.
    Inventors: Bao-Gang Wu, Jianmi Gao, Hongxi Zhou, Yao-Dong Ma
  • Patent number: 5825451
    Abstract: Methods of manufacturing a liquid crystal display ("LCD"); specifically, a multi-color LCD, e.g., a red-green-blue ("RGB") LCD. The methods include the steps of: (1) depositing a twist agent on a first substrate, the twist agent becoming an in situ twist agent, (2) bringing a second substrate into proximity with the first substrate to form at least one interstitial region between the second and first substrates, (3) introducing liquid crystal ("LC") having an initial pitch into the at least one interstitial region proximate the in situ twist agent and (4) stimulating the LC and the in situ twist agent to cause the LC and the in situ twist agent to mix in situ, the in situ twist agent changing the initial pitch of the LC.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: October 20, 1998
    Assignee: Advanced Display Systems, Inc.
    Inventors: Yao-Dong Ma, Bao-Gang Wu
  • Patent number: 5661533
    Abstract: Surfactant-containing multistable cholesteric liquid crystal displays exhibit ultra fast response times with both video speed and gray scale capability.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: August 26, 1997
    Assignee: Advanced Display Systems, Inc.
    Inventors: Bao-Gang Wu, Hongxi Zhou, Yao-Dong Ma
  • Patent number: 5625477
    Abstract: A light modulating apparatus containing cholesteric liquid crystals capable of indefinite zero field retention of optical images, including full color and complete gray scale capability, is described. This invention is predicated on establishment of zero field multistable liquid crystal domains representing a continuous distribution of states ranging from the highly reflective planar to the light-scattering focal-conic structures. The zero field multistable domain structure stability is achieved by controlling solid surface-liquid crystal boundary interactions to provide essential equalization of the total system energy of each of the domain structures. This is the first time this equalization, and thus zero field multistability, has been achieved without the use of a polymer gel addition to create rigid polydomains in the liquid crystal mix.
    Type: Grant
    Filed: April 11, 1994
    Date of Patent: April 29, 1997
    Assignee: Advanced Display Systems, Inc.
    Inventors: Bao-Gang Wu, Jianmi Gao, Hongxi Zhou, Yao-Dong Ma
  • Patent number: 4890902
    Abstract: A light modulating material comprising phase-separated microdroplets of liquid crystal in a light transmissive, synthetic resin matrix wherein the index of refraction n.sub.p of the matrix is matched or mismatched to an index of refraction N.sub.o of the liquid crystal optical axis of the microdroplets so that when the microdroplet director is aligned relative to a surface of the material, maximum transmission of light occurs at a selected oblique angle relative to the surface of the material or at a selected narrow angle about the perpendicular to the surface of the material. Such matching or mismatching of indices of refraction may be accompanied by phase separation in an external magnetic or electric field, or by shaping the liquid crystal microdroplet into an ovoid or the like during or after phase separation to align the microdroplet directors thereby endowing the material with a permanent and movable viewing angle.
    Type: Grant
    Filed: February 23, 1988
    Date of Patent: January 2, 1990
    Assignee: Kent State University
    Inventors: J. William Doane, Eugene P. Wenninger, John West, Bao-Gang Wu
  • Patent number: 4671618
    Abstract: The invention provides a new liquid crystal-plastic display material having submillisecond switching times and an electrooptic bistable memory. The material comprises microdroplets of liquid crystal dispersed in a plastic matrix, the liquid crystal being present in an amount of at least 50% by weight. The material is prepared by the phase separation of a homogeneous solution of liquid crystal and synthetic polymer. Phase separation results in a liquid crystalline rich phase in the form of microdroplets and a plastic rich phase containing dissolved liquid crystal in solid solution with the plastic.
    Type: Grant
    Filed: June 27, 1986
    Date of Patent: June 9, 1987
    Inventors: Bao-Gang Wu, J. William Doane