Patents by Inventor Youichi Honzawa

Youichi Honzawa 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 transmitter
    Patent number: 8098998
    Abstract: A technology to automatically control the biasing of an optical duobinary transmitter using a single-drive LN-MZ modulator is provided. A low-frequency signal is amplitude modulated onto a voltage signal input into a Mach-Zehnder optical modulator 22. The optical output from the optical modulator 22 is detected by an optical detection subsystem 30. In a bias control subsystem 40, the low-frequency signal component amplitude modulated onto the electrical signal is detected from the optical output, and a DC bias voltage applied to the optical modulator is controlled such that the low-frequency signal component is either minimized or maximized.
    Type: Grant
    Filed: April 23, 2008
    Date of Patent: January 17, 2012
    Assignee: Opnext Japan, Inc.
    Inventors: Shigehiro Takashima, Takayoshi Fukui, Yoshikuni Uchida, Kazuyoshi Yamaki, Youichi Honzawa
  • OPTICAL TRANSMITTER
    Publication number: 20090060528
    Abstract: A technology to automatically control the biasing of an optical duobinary transmitter using a single-drive LN-MZ modulator is provided. A low-frequency signal is amplitude modulated onto a voltage signal input into a Mach-Zehnder optical modulator 22. The optical output from the optical modulator 22 is detected by an optical detection subsystem 30. In a bias control subsystem 40, the low-frequency signal component amplitude modulated onto the electrical signal is detected from the optical output, and a DC bias voltage applied to the optical modulator is controlled such that the low-frequency signal component is either minimized or maximized.
    Type: Application
    Filed: April 23, 2008
    Publication date: March 5, 2009
    Inventors: Shigehiro TAKASHIMA, Takayoshi Fukui, Yoshikuni Uchida, Kazuyoshi Yamaki, Youichi Honzawa