Patents by Inventor Peter Van De Witte

Peter Van De Witte 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: 6628354
    Abstract: In normally black double cells, the viewing angle (especially for DSTN) is increased by adding a retardation foil, having its optical axis parallel to an optical axis of the analyzer.
    Type: Grant
    Filed: July 10, 2002
    Date of Patent: September 30, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Peter Van De Witte, Sjoerd Stallinga
  • Publication number: 20030137617
    Abstract: Transflective display device provided with an optical waveguide which splits light coming in from aside into two light beams having a mutually opposite circular polarization. Polarization splitting is achieved at the interface of areas in the optical waveguide having a chiral nematic structure.
    Type: Application
    Filed: January 13, 2003
    Publication date: July 24, 2003
    Inventors: Hugo Johan Cornelissen, Dirk Jan Broer, Peter Van De Witte
  • Patent number: 6597856
    Abstract: The invention relates to a method of manufacturing a patterned layer of a polymer material having a cholesteric order, in which the material is oriented in such a way that the axis of the molecular helix of the cholesterically ordered material extends transversely to the layer, and in which the layer is patterned in that it comprises at least one region in which the pitch of the molecular helix differs from that of another region. This inventive method comprises the following steps: a. providing a layer of a cholesterically ordered material comprising a quantity of a convertible compound which in its non-converted and in its converted state determines the pitch of the cholesterically ordered material to a different extent, in which the conversion of said compound may be induced by radiation, b. irradiating the layer in accordance with a desired pattern so that at least a part of the convertible compound in the irradiated parts of the layer is converted, c.
    Type: Grant
    Filed: August 9, 2002
    Date of Patent: July 22, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Peter Van De Witte, Johan Lub
  • Patent number: 6545734
    Abstract: Transflective display device provided with an optical waveguide which splits light coming in from aside into two light beams having a mutually opposite circular polarization. Polarization splitting is achieved at the interface of areas in the optical waveguide having a chiral nematic structure.
    Type: Grant
    Filed: December 27, 2000
    Date of Patent: April 8, 2003
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Hugo Johan Cornelissen, Dirk Jan Broer, Peter Van De Witte
  • Publication number: 20030025861
    Abstract: This invention relates to a liquid crystal display device, comprising at least one retardation film (4), a nematic liquid crystal layer (5), and a light reflecting RGB patterned cholesteric color filter (6), for reflecting either essentially left-circular or right-circular polarized light, being characterized in that said liquid crystal layer (5) is a super twisted nematic liquid crystal layer having a twist angle in the interval 180-270 degrees, and in that the summed retardation R of the retardation film or retardation films and the liquid crystal layer is equal to approximately R=(3+2n)&lgr;/4, where n=0,1,2,3 . . . .
    Type: Application
    Filed: July 30, 2002
    Publication date: February 6, 2003
    Inventors: Joost Peter Andre Vogels, Frans Leenhouts, Peter Van De Witte
  • Publication number: 20020191129
    Abstract: In normally black double cells, the viewing angle (especially for DSTN) is increased by adding a retardation foil, having its optical axis parallel to an optical axis of the analyzer.
    Type: Application
    Filed: July 10, 2002
    Publication date: December 19, 2002
    Applicant: KONINKLIJKE PHILIPS ELECTRONICS, N. V.
    Inventors: Peter Van De Witte, Sjoerd Stallinga
  • Publication number: 20020191945
    Abstract: The invention relates to a method of manufacturing a patterned layer of a polymer material having a cholesteric order, in which the material is oriented in such a way that the axis of the molecular helix of the cholesterically ordered material extends transversely to the layer, and in which the layer is patterned in that it comprises at least one region in which the pitch of the molecular helix differs from that of another region.
    Type: Application
    Filed: August 9, 2002
    Publication date: December 19, 2002
    Applicant: U.S. PHILIPS CORPORATION
    Inventors: Peter Van De Witte, Johan Lub
  • Patent number: 6459847
    Abstract: The invention relates to a method of manufacturing a patterned layer of a polymer material having a cholesteric order, in which the material is oriented in such a way that the axis of the molecular helix of the cholesterically ordered material extends transversely to the layer, and in which the layer is patterned in that it comprises at least one region in which the pitch of the molecular helix differs from that of another region. This inventive method comprises the following steps: a. providing a layer of a cholesterically ordered material comprising a quantity of a convertible compound which in its non-converted and in its converted state determines the pitch of the cholesterically ordered material to a different extent, in which the conversion of said compound may be induced by radiation, b. irradiating the layer in accordance with a desired pattern so that at least a part of the convertible compound in the irradiated parts of the layer is converted, c.
    Type: Grant
    Filed: August 7, 2000
    Date of Patent: October 1, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Peter Van De Witte, Johan Lub
  • Patent number: 6437843
    Abstract: In normally black double cells, the viewing angle (especially for DSTN) is increased by adding a retardation foil, having its optical axis parallel to an optical axis of the analyzer.
    Type: Grant
    Filed: April 3, 2000
    Date of Patent: August 20, 2002
    Assignee: Koninklijke Philips Electronics N.V.
    Inventors: Peter Van De Witte, Sjoerd Stallinga
  • Publication number: 20020067449
    Abstract: Multi-domains are obtained in a liquid crystal cell by introducing different orientation directions at the area of pixel walls.
    Type: Application
    Filed: July 2, 2001
    Publication date: June 6, 2002
    Inventors: Peter Van De Witte, Josephus Paulus Augustinus Deeben, Armanda Cinderella Nieuwkerk
  • Publication number: 20010055089
    Abstract: In a method of manufacturing a liquid crystal device including a layer having a fixed cholesteric order, the patterned layer is manufactured by providing a layer comprising polymerizable cholesterically ordered material and a compound convertible by means of radiation from a non-converted to converted state. The pitch of the cholesterically ordered material is influenced by the compound in its converted state to a different extent than in its converted state. The polymerizable layer is then irradiated pattern-wise thus creating regions of different pitch. The irradiated layer is then polymerized and/or cross-linked to fix the cholesteric order thus obtained.
    Type: Application
    Filed: May 18, 2001
    Publication date: December 27, 2001
    Applicant: U.S. PHILIPS CORPORATION
    Inventors: Peter Van De Witte, Michael Geoffrey Pitt
  • Publication number: 20010050734
    Abstract: Transflective display device provided with an optical waveguide which splits light coming in from aside into two light beams having a mutually opposite circular polarization. Polarization splitting is achieved at the interface of areas in the optical waveguide having a chiral nematic structure.
    Type: Application
    Filed: December 27, 2000
    Publication date: December 13, 2001
    Inventors: Hugo Johan Cornelissen, Dirk Jan Broer, Peter Van De Witte
  • Publication number: 20010046015
    Abstract: The invention relates to a method of providing a decorative coating or text or the like on articles, like shavers, GSM's, cards, etc. The coating comprises a region-wise optically modified (patterned) cholesteric liquid crystalline layer, which is transferred onto a surface of the article by means of a transfer operation. The so-called in-mold decoration technique has been found to be very advantageous for the transfer of decorative (patterned) cholesteric liquid crystalline layers. In this technique the layer is (releasably) deposited on a plastic carrier foil and provided with a layer of adhesive. The assembly is inserted in an injection mold before the injection molding of polymer material starts. In this way decorative coatings (e.g. multi color images) and texts or the like can be even applied onto, non-even and slightly curved substrates.
    Type: Application
    Filed: April 16, 2001
    Publication date: November 29, 2001
    Applicant: Koninklijke Philips Electronics N.V.
    Inventors: Peter Van De Witte, Johan Lub
  • Publication number: 20010043298
    Abstract: In the case of a twisted nematic LCD of the dual-domain type, a better viewing-angle dependence is achieved by providing a birefringent retardation foil on the side where the liquid crystal molecules are uniformly oriented, the optical axis of said retardation foil extending in a plane parallel to said orientation.
    Type: Application
    Filed: February 11, 1999
    Publication date: November 22, 2001
    Inventors: SJOERD STALLINGA, PETER VAN DE WITTE
  • Patent number: 5978055
    Abstract: A compensator (for example, for a liquid-crystal display device) comprising a retardation foil with a tilted optical main axis and, in addition, a second optically active layer, can be manufactured in a simple manner by providing the retardation foil and the second layer on different sides of a transparent support.
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: November 2, 1999
    Assignee: U.S. Philips Corporation
    Inventors: Peter Van De Witte, Johannes A. M. M. Van Haaren, Dirk J. Broer, Sjoerd Stallinga
  • Patent number: 5936692
    Abstract: The invention relates to a multi-domain liquid-crystal display device comprising two substantially parallel substrates which are provided with an electrode layer and an orientation layer. A layer of a nematically ordered liquid-crystalline material comprising a chiral dopant is sandwiched between the substrates. The layer is structured in such a manner that the pixels of the layer are composed of at least two types of sub-pixels in which the twist senses of the liquid-crystalline material are mutually opposite. This construction in accordance with the invention is achieved by differentiating the composition of the chiral dopant in the different types of sub-pixels. This is attained by employing isomerizable chiral dopants and/or diffusion techniques in combination with local exposure of the liquid-crystal layer. The invention also provides methods of manufacturing such multi-domain liquid-crystal display devices.
    Type: Grant
    Filed: June 2, 1998
    Date of Patent: August 10, 1999
    Assignee: U.S. Philips Corporation
    Inventor: Peter Van De Witte