Patents by Inventor Kazushi Hashimoto

Kazushi Hashimoto 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).

  • Filter device and dual-band radio system in which the filter device is used
    Patent number: 6115592
    Abstract: A filter device includes at least two filter elements provided in a package, each of the filter elements passing only signals within a predetermined frequency band, the predetermined frequency bands of the filter elements having center frequencies which are distinct from each other. An input terminal is connected to and shared by respective inputs of the filter elements. An output terminal is connected to and shared by respective outputs of the filter elements.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: September 5, 2000
    Assignee: Fujitsu Limited
    Inventors: Masanori Ueda, Osamu Ikata, Hideki Ohmori, Yoshiro Fujiwara, Kazushi Hashimoto
  • Surface acoustic wave filter with larger driving electrode areas in some parallel resonators, and packaging thereof
    Patent number: 5914646
    Abstract: A surface acoustic wave filter element is formed by replacing with a single parallel resonator having a driving electrode whose area is equal to the sum total of the areas of driving electrodes of a plurality of consecutive parallel resonators arranged in a ladder shape, together with serial resonators, for structuring a surface acoustic wave resonator. Also, in a surface acoustic wave filter formed by packaging the surface acoustic wave filter element, ground electrodes of the parallel resonators of the filter element are electrically insulated from each other and are connected to different electrode pads for grounding.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: June 22, 1999
    Assignee: Fujitsu Limited
    Inventor: Kazushi Hashimoto
  • Surface acoustic wave filter duplexer comprising a multi-layer package and phase matching patterns
    Patent number: 5786738
    Abstract: In a duplexer, phase matching circuit patterns corresponding to filter chips are formed on a surface layer of a multi-layer ceramic package provided with filter chips having different central frequencies. An end of each of the phase matching circuit patterns is connected to a common terminal pattern.
    Type: Grant
    Filed: May 31, 1996
    Date of Patent: July 28, 1998
    Assignee: Fujitsu Limited
    Inventors: Osamu Ikata, Nobuo Hirasawa, Kazushi Hashimoto, Masanori Ueda, Yoshio Satoh
  • Acoustic surface wave element
    Patent number: 4978879
    Abstract: An acoustic surface wave element having an oscillation frequency stable against temperature changes, and a wide range of oscillation frequency adjustment, is provided by an acoustic surface wave element comprising: a substrate of a 36.degree. rotated Y-cut single crystal lithium tantalate having X, Y and Z crystal axes and a top surface and side walls; electrodes formed on the top surface of the substrate such that an acoustic surface wave is propagated in a direction of the X-axis of the substrate and an oscillation of the acoustic surface wave occurs at a predetermined frequency, the electrodes having a thickness equal to 1 to 4% of a wavelength of the acoustic surface wave at the oscillation; and a plasma CVD-deposited layer of silicon dioxide covering the electrodes and the substrate, the silicon dioxide layer having a refractive index of 1.445 to 1.486 and a thickness equal to 16 to 26% of the wavelength of the acoustic surface wave at the oscillation.
    Type: Grant
    Filed: July 25, 1989
    Date of Patent: December 18, 1990
    Assignee: Fujitsu Limited
    Inventors: Kiyoshi Satoh, Yoshiro Fujiwara, Kazushi Hashimoto