Patents by Inventor Kunihiko Takeshige

Kunihiko Takeshige 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).

  • Method to fabricate frequency doubler devices
    Patent number: 5205904
    Abstract: A method to fabricate nonlinear optical frequency doubler devices comprised of a process to form periodic tantalum masks on a LiNb.sub.x Ta.sub.1-x O.sub.3 (wherein 0.ltoreq.x.ltoreq.1) crystal substrate, a process to form periodic proton exchanged regions by applying a phosphoric acid treatment, and a process to form an optical waveguide on the surface of said crystal.According to this fabrication method of the present invention, deeper domain-inverted regions can be formed on said crystal surface, and by this, a fundamental wave can be transformed into a harmonic wave at a high efficiency.
    Type: Grant
    Filed: March 13, 1991
    Date of Patent: April 27, 1993
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kazuhisa Yamamoto, Kunihiko Takeshige, Tetsuo Taniuchi