Patents by Inventor Sadao Yokoo

Sadao Yokoo 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).

  • Protective cover
    Patent number: 4634270
    Abstract: A protective cover for photoprinting system comprises a cover portion made of a transparent thin plate of inorganic material, an antireflection multiple coating provided on at least one of the inner and outer surfaces of the cover plate, and a spacer arranged on the peripheral portion of the cover plate for keeping the inner surface of the cover plate away from the surface to be protected, e.g., pattern surface of photomask and sealing the space between them.Since the cover plate is made of inorganic material, the mechanical strength thereof is large. Since the cover plate is thin and the antireflection multiple coating is provided on the cover plate, absorption of light therein is little and confusion of the pattern image due to rays reflected by the boundaries of the cover plate is ignorable.
    Type: Grant
    Filed: October 18, 1985
    Date of Patent: January 6, 1987
    Assignees: Nippon Sheet Glass Co., Ltd., Hitachi Ltd., Hitachi Microcomputer Engineering Ltd.
    Inventors: Sadao Yokoo, Tadashi Shimomura, Soichi Torisawa, Masahiro Dan, Tsuyoshi Kaneda