Patents Assigned to Koito Seisakusko Co., Ltd.
  • Patent number: 4949226
    Abstract: A vehicle headlamp having a projector-type light source assembly capable of emitting a highly coherent light beam. In order to make the headlamp appear larger than the light source assembly, a lamp housing is provided which is much larger in size than the light source assembly mounted therein, with the consequent provision of an annular space around the light source assembly within the lamp housing. Disposed in this annular space is an outline expander plate of transparent material having a multiplicity of minute cavities of cone shape formed in its rear face. The outline expander plate transmits by internal total reflection the light incident edgewise thereon. While so traveling through the outline expander plate, the light is reflected by the surfaces of the conical cavities generally in the forward direction of the headlamp, thereby making the complete surface area of the headlamp appear glowing.
    Type: Grant
    Filed: June 23, 1989
    Date of Patent: August 14, 1990
    Assignee: Koito Seisakusko Co., Ltd.
    Inventors: Hiroyuki Makita, Takahisa Shinoda, Yasuaki Nakamura, Osamu Endoh