Patents by Inventor Tomoaki Hirakawa

Tomoaki Hirakawa 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).

  • Patent number: 6147934
    Abstract: In a display device used in an electronic watch or the like, information such as numeric characters or the like and a background are bright and easily displayed. In addition, various information is provided to a viewer, and attracting the viewer's interest is facilitated. The display device includes components of a polarizer, a liquid crystal panel and a polarization separation film. The polarization separation film has a function of transmitting linearly polarized light in one direction and of reflecting other linearly polarized light. A pattern such as a logo, a mark, a character or the like is formed by printing on a light-reflecting layer provided at the back of the polarization separation film. Information such as numeric characters or the like is not displayed as a background of a single color with no pattern, but after rendering a pattern such as a character or the like a background, both information such as numeric characters or the like and the background can be displayed simultaneously.
    Type: Grant
    Filed: June 8, 1998
    Date of Patent: November 14, 2000
    Assignee: Seiko Epson Corporation
    Inventors: Yasuo Arikawa, Eiichi Miyazawa, Tomoaki Hirakawa