Patents by Inventor Kazuhiro Umeki

Kazuhiro Umeki 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).

  • Exposure mask, method of producing the same, exposure mask producing apparatus, and method of forming surface profile on material using exposure mask
    Patent number: 5776639
    Abstract: A two-dimensional shape of a dotted pattern and optical densities of dots or sizes of dots having the same optical density are calculated as write data on the basis of a target distribution of transmittance. The dotted pattern is optically written on a photosensitive medium in accordance with the calculated write data, using a beam from a light source whose output is stepwise or sequentially variable. A latent dotted pattern on the photosensitive medium is developed, thereby obtaining an exposure mask having a desired two-dimensional distribution of transmittance expressed by the dotted pattern and the optical densities of dots or the sizes of dots having the same optical density.
    Type: Grant
    Filed: April 8, 1996
    Date of Patent: July 7, 1998
    Assignee: Ricoh Optical Industries, Co., Ltd.
    Inventors: Kazuhiro Umeki, Shosen Sato
  • Optical information recording medium
    Patent number: 5368908
    Abstract: An optical information recording medium, for writing in and reading out information by a laser beam, is composed of a recording layer, an anti-reflection layer structure formed on an outer surface section on which the laser beam is directed to be focused, on the recording layer, and the anti-reflection layer structure includes one or more transparent electroconductive film layers.
    Type: Grant
    Filed: July 8, 1991
    Date of Patent: November 29, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Wasaburo Ohta, Isamu Orima, Masashi Nakazawa, Yuzi Onodera, Kazuhiro Umeki