Patents by Inventor Hideki Murakawa

Hideki Murakawa 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 transmission module
    Patent number: 7035302
    Abstract: The present invention provides an optical transmission module having a laser diode that generates laser beams and a differential type current switch provided with a first switch and a second switch in order to supply a modulating current to the laser diode. A terminal of the laser diode and the first switch are connected in series through a first transmission line and a first capacitor, the other terminal of the laser diode and the second switch are connected in series through a second transmission line and a second capacitor. The current driven by the second switch is terminated by a resistor connected to the first switch and the current driven by the first switch is terminated by a resistor connected to the second switch. Thus, the laser diode is modulated bidirectionally.
    Type: Grant
    Filed: March 6, 2003
    Date of Patent: April 25, 2006
    Assignee: OpNext Japan, Inc.
    Inventors: Tomokazu Tanaka, Cleitus Antony, Hiroo Matsue, Hideki Murakawa, Tadashi Hatano
  • Optical transmission module
    Publication number: 20040114650
    Abstract: The present invention provides an optical transmission module having a laser diode that generates laser beams and a differential type current switch provided with a first switch and a second switch in order to supply a modulating current to the laser diode. A terminal of the laser diode and the first switch are connected in series through a first transmission line and a first capacitor, the other terminal of the laser diode and the second switch are connected in series through a second transmission line and a second capacitor. The current driven by the second switch is terminated by a resistor connected to the first switch and the current driven by the first switch is terminated by a resistor connected to the second switch. Thus, the laser diode is modulated bidirectionally.
    Type: Application
    Filed: March 6, 2003
    Publication date: June 17, 2004
    Applicant: OpNext Japan, Inc.
    Inventors: Tomokazu Tanaka, Cleitus Antony, Hiroo Matsue, Hideki Murakawa, Tadashi Hatano