Patents by Inventor Hirohiko Sonada

Hirohiko Sonada 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: 6392784
    Abstract: An object of the invention is to provide a small size Faraday rotator which is easy to produce and enables reliable reduction of temperature dependence of the Faraday rotation angle, by defining the crystal orientation and arrangement order of each Faraday element when three or more Faraday elements are used. For this purpose, a Faraday rotator of the present invention comprises: a Faraday element section being composed of a plurality of Faraday elements, a permanent magnet for applying a magnetic field to each Faraday element in a parallel direction to an optical axis direction, and an electromagnet for applying a variable magnetic field in a perpendicular direction to the optical axis direction, wherein each Faraday element is arranged such that the crystal orientation of each is perpendicular to a light beam direction, and crystal orientations of adjacent Faraday elements are opposed to each other.
    Type: Grant
    Filed: May 24, 2000
    Date of Patent: May 21, 2002
    Assignee: Fujitsu Limited
    Inventors: Seiichi Ikeda, Nobuhiro Fukushima, Hirohiko Sonada