Patents by Inventor Chiharu Takahashi

Chiharu Takahashi 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).

  • Photonic crystal waveguide
    Patent number: 6643439
    Abstract: A two-dimensional photonic crystal slab waveguide is provided in which a line defect is formed, wherein a first width which is a distance between centers of nearest two lattice points located on both sides of the line defect is different from a second width which is a corresponding distance in a normal two-dimensional photonic crystal slab waveguide. In addition, a two-dimensional photonic crystal slab waveguide is provided in which low refractive index columns in a optical waveguide part are placed at positions shifted from normal positions in a normal two-dimensional photonic crystal slab.
    Type: Grant
    Filed: December 26, 2001
    Date of Patent: November 4, 2003
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Masaya Notomi, Koji Yamada, Akihiko Shinya, Junichi Takahashi, Chiharu Takahashi, Itaru Yokohama
  • Photonic crystal waveguide
    Publication number: 20020118941
    Abstract: A two-dimensional photonic crystal slab waveguide is provided in which a line defect is formed, wherein a first width which is a distance between centers of nearest two lattice points located on both sides of the line defect is different from a second width which is a corresponding distance in a normal two-dimensional photonic crystal slab waveguide. In addition, a two-dimensional photonic crystal slab waveguide is provided in which low refractive index columns in a optical waveguide part are placed at positions shifted from normal positions in a normal two-dimensional photonic crystal slab.
    Type: Application
    Filed: December 26, 2001
    Publication date: August 29, 2002
    Inventors: Masaya Notomi, Koji Yamada, Akihiko Shinya, Junichi Takahashi, Chiharu Takahashi, Itaru Yokohama
  • Flowmeter calibration method
    Patent number: 5648605
    Abstract: A flowmeter calibration method includes disposing a flowmeter on a standard flowpath, disposing a flowmeter on each of a plurality of branch flowpaths in communication with the standard flowpath, using the flowmeters disposed on the flowpaths to vary a fluid flow through each flowpath and measuring each flow value, and comparing the plurality of flow values thus obtained to obtain the relative instrumental error of each flowmeter.
    Type: Grant
    Filed: August 23, 1995
    Date of Patent: July 15, 1997
    Assignee: Agency of Industrial Science & Technology, Ministry of International Trade & Industry
    Inventor: Chiharu Takahashi