Patents Assigned to Minolata Co., Ltd.
  • Diffractive optical element and method of manufacturing a mold
    Patent number: 6590709
    Abstract: A diffractive optical element acts as a lens. The optical element has a diffraction grating. The diffractive grating is provided with a plurality of ridges. Each of the ridges has a transmissive surface. A sectional profile of the transmissive surface is composed of a plurality of successively connected strait lines of an identical length. The length varies from one ridge to another.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: July 8, 2003
    Assignee: Minolata Co., Ltd.
    Inventors: Yuichiro Ori, Koji Miyai, Hiromu Mukai, Shigeto Ohmori