Patents by Inventor Ryotomo Sirakawa

Ryotomo Sirakawa 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: 5093880
    Abstract: An optical fiber cable free from a generation of a microbent during manufacturing, and in which an impregnation of hydrogen and/or water to a cladding is prevented, and having high electrical conduction, tolerance to heat and mechanical strength, and a process for making same. The optical fiber cable includes a silica based glass optical fiber including a core and a cladding, a thin carbon coating formed on an outer surface of the optical fiber, and an electrically conductive coating formed on an outer surface of the carbon coating. The carbon coating functions as a layer for preventing the impregnation of hydrogen and/or water to the optical fiber, and the conductive coating functions as a heat tolerance member, a conductive member, and a mechanical support member. The carbon coating is preferably formed as an amorphous carbon layer.
    Type: Grant
    Filed: August 27, 1990
    Date of Patent: March 3, 1992
    Assignee: Furukawa Electric Co., Ltd.
    Inventors: Akira Matsuda, Akira Iino, Ryotomo Sirakawa