Patents by Inventor Kouichi Fujisaki

Kouichi Fujisaki 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 multiplexing circuit and optical multiplexer
    Patent number: 6842560
    Abstract: A part of a wavelength division multiplexed optical signal output from a multiplexing area is extracted as a check signal, and then the extracted signal is guided to a multiplexing area. A reentered check signal is detected at a facet located opposite a facet from which the check signal has been reentered, and the state of the detected check signal is determined. Furthermore at need, on the basis of the result of the determination, a control signal is output that controls operations of a plurality of optical signals input to the multiplexing area.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: January 11, 2005
    Assignees: NTT Electronics Corporation, Nippon Telegraph and Telephone Corporation
    Inventors: Yoshiki Yamauchi, Kouichi Fujisaki, Akimasa Kaneko, Takashi Asaoka, Yoshihisa Sakai
  • Optical multiplexing circuit and optical multiplexer
    Publication number: 20020126341
    Abstract: A part of a wavelength division multiplexed optical signal output from a multiplexing area is extracted as a check signal, and then the extracted signal is guided to a multiplexing area. A reentered check signal is detected at a facet located opposite a facet from which the check signal has been reentered, and the state of the detected check signal is determined. Furthermore at need, on the basis of the result of the determination, a control signal is output that controls operations of a plurality of optical signals input to the multiplexing area.
    Type: Application
    Filed: February 26, 2002
    Publication date: September 12, 2002
    Applicant: NTT ELECTRONICS CORPORATION and NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Yoshiki Yamauchi, Kouichi Fujisaki, Akimasa Kaneko, Takashi Asaoka, Yoshihisa Sakai