Patents by Inventor Yoichi Kanagawa

Yoichi Kanagawa 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).

  • Optical isolator, optical isolator with fiber and method for making the same
    Patent number: 5691845
    Abstract: In an optical isolator including first and second birefringent plates whose optical axes are angularly different and a Faraday rotator inserted therebetween having a Faraday rotation angle of .theta..sub.f, (1) the angles of the optical axes of the first and second birefringent plates are so set that a forward incident polarized light passes through the first and second birefringent plates both as ordinary lights or both as extraordinary lights, and the relationship .theta..sub.f +.phi..sub.eff =90.degree. is satisfied when an actually used incident polarized light is incident in an oblique direction, or (2) the angles of the optical axes of the first and second birefringent plates are so set that a forward incident polarized light passes through one of the first and second birefringent plates as an ordinary light and the other birefringent plate as an extraordinary light, and the relationship .theta..sub.f -.phi..sub.eff =0.degree. is satisfied.
    Type: Grant
    Filed: August 10, 1995
    Date of Patent: November 25, 1997
    Assignee: TDK Corporation
    Inventors: Shinji Iwatsuka, Yoichi Kanagawa, Kenjiro Hata, Makoto Sekijima
  • Sintered ferrite body, chip inductor, and composite LC part
    Patent number: 5206620
    Abstract: A ferrite composition comprising ferrite, borosilicate glass, and optionally boron oxide can be fired at a relatively low temperature of up to 950.degree. C. into a sintered body having improved mechanical strength and electromagnetic properties. The sintered ferrite body is used to form a chip inductor. The inductor is combined with a capacitor to form a composite LC part.
    Type: Grant
    Filed: June 18, 1990
    Date of Patent: April 27, 1993
    Assignee: TDK Corporation
    Inventors: Hideo Watanabe, Yoichi Kanagawa, Takashi Suzuki, Takeshi Nomura
  • Sintered ferrite body, chip inductor, and composite LC part
    Patent number: 4956114
    Abstract: A ferrite composition comprising ferrite, borosilicate glass, and optionally boron oxide can be fired at a relatively low temperature of up to 950.degree. C. into a sintered body having improved mechanical strength and electromagnetic properties. The sintered ferrite body is used to form a chip inductor. The inductor is combined with a capacitor to form a composite LC part.
    Type: Grant
    Filed: June 29, 1988
    Date of Patent: September 11, 1990
    Assignee: TDK Corporation
    Inventors: Hideo Watanabe, Yoichi Kanagawa, Takashi Suzuki, Takeshi Nomura