Patents by Inventor Harumichi Tsukada

Harumichi Tsukada 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 information recording medium
    Patent number: 5413893
    Abstract: An optical information recording medium comprises (1) a base, (2) at least one recording film provided on the base, being capable of bringing about a change in light tranmittance upon being exposed to an optical and/or thermal energy of an incident laser beam, and (3) a reflective film provided on the recording film. The optical information recording medium can exhibit a high contrast and is interexchangeable with CD and LV.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: May 9, 1995
    Assignee: Daicel Chemical Industries, Ltd.
    Inventors: Harumichi Tsukada, Etsuji Akimoto, Masahiro Tsumura