Patents by Inventor Tadashi Yamakawa

Tadashi Yamakawa 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).

  • Image forming apparatus
    Patent number: 4571053
    Abstract: An image forming apparatus comprises a light source, a photosensitive member adopted to be illuminated by a light from the light source, a liquid crystal for controlling illumination and non-illumination of the light to the photosensitive member to form an image on the photosensitive member, a detector for detecting an image reproduction ability of the photosensitive member to set an image forming condition on the photosensitive member, and setting means for setting the liquid crystal to a predetermined state to allow the detection by the detector.
    Type: Grant
    Filed: September 18, 1984
    Date of Patent: February 18, 1986
    Assignee: Canon Kabushiki Kaisha
    Inventors: Nobuhiro Kasama, Mitsuru Kurata, Hiroshi Tanioka, Tadashi Yamakawa, Yutaka Inoue, Masao Hosaka, Toshiaki Yagasaki