Patents by Inventor Keiichi Sugimura

Keiichi Sugimura 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).

  • Semiconductor laser output control circuit
    Patent number: 4835780
    Abstract: A semiconductor laser output control apparatus for controlling a drive current to be supplied to a semiconductor laser which is turned on and off so as to maintain a light output from the semiconductor laser at constant. At the rising edge when the semiconductor laser is turned on, constant current supplied from a constant current source to the semiconductor laser is corrected by correction current.
    Type: Grant
    Filed: September 7, 1988
    Date of Patent: May 30, 1989
    Assignee: Ricoh Company, Ltd.
    Inventors: Keiichi Sugimura, Yoshinobu Takeyama, Kazuyuki Shimada