Patents by Inventor Isao Hamashima

Isao Hamashima 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).

  • Planar light source and display device using the same
    Patent number: 6425675
    Abstract: A planar light source device includes a light source 2, a reflector shade 8, a light guide member 3 having at least one side face 1 positioned adjacent the light source for receiving light from the light source and reflected by the reflector shade, and a light output plate 4 positioned adjacent the light guide member 3 with a first surface positioned adjacent a light exit surface of the light guide member 3. The first surface is formed with a multiplicity of projections 7 having respective tips held in tight contact with the light exit surface of the light guide member 3, at least a portion of each of the projections 7 having a curved facet. Of a function descriptive of a sectional shape of each of the projections 7 that is parallel to a direction of travel of light and also a direction normal to the light output plate 4, the maximum value of the absolute value of a linear differential of a portion representative of a facet counter to the light source is chosen to be within the range of 1 to 3.
    Type: Grant
    Filed: April 25, 2001
    Date of Patent: July 30, 2002
    Assignee: Kuraray Co., Ltd.
    Inventors: Ikuo Onishi, Katsuya Fujisawa, Isao Hamashima, Shinji Hiramatsu, Yoichi Hashimoto
  • Planar light source and display device using the same
    Publication number: 20010053074
    Abstract: A planar light source device includes a light source 2, a reflector shade 8, a light guide member 3 having at least one side face 1 positioned adjacent the light source for receiving light from the light source and reflected by the reflector shade, and a light output plate 4 positioned adjacent the light guide member 3 with a first surface positioned adjacent a light exit surface of the light guide member 3. The first surface is formed with a multiplicity of projections 7 having respective tips held in tight contact with the light exit surface of the light guide member 3, at least a portion of each of the projections 7 having a curved facet. Of a function descriptive of a sectional shape of each of the projections 7 that is parallel to a direction of travel of light and also a direction normal to the light output plate 4, the maximum value of the absolute value of a linear differential of a portion representative of a facet counter to the light source is chosen to be within the range of 1 to 3.
    Type: Application
    Filed: April 25, 2001
    Publication date: December 20, 2001
    Applicant: KURARAY CO., LTD.
    Inventors: Ikuo Onishi, Katsuya Fujisawa, Isao Hamashima, Shinji Hiramatsu, Yoichi Hashimoto