Nippondenso Co., Ltd.

Denso Corporation

Shinji Namba

Toshio Hosokawa

Takekazu Terui

Kazutoshi Koie

Hirosi Ando

Naoki Fukaya

Yasunori Kanno

A radar apparatus comprises a rotary polygon mirror with a plurality of mirror surfaces inclined at different angles. A semiconductor laser diode and a collimator lens are disposed above the polygon mirror. An infrared pulse beam emitted from the semiconductor laser diode is reflected by a reflection mirror disposed at an upper position in front of the polygon mirror to reflect the pulse beam obliquely downward toward the rotary polygon mirror so that the pulse beam is reflected as a transmission beam advancing toward a measuring area in a forward direction. A light receiving means receives the transmission beam returned from an object positioned within the measuring area.

Radar apparatus and a vehicle safe distance control system using this

A rear indicator device for an automobile arranged inwardly of and adjacent to a rear window. The device includes a light guide plate 2, a hologram 2 arranged in the light guide plate 2 and an irregular shaped prism having a first section having an apex angle .phi.1 at which the light beam from a light source 5 is subjected to a refraction so that the light beam is flattened. The flattened beam is again introduced into the prism at a second section which is in face to face contact with the light guide plate 2, so that the light beam is transmitted inside the light guide plate 2 toward the hologram 3, whereat the light beam is introduced into the hologram at a predetermined angle of incidence, so that a horizontal light beam of a predetermined wave length is obtained in a rear direction of the automobile to indicate the braking of the automobile.

Rear indicating device for an automobile

A light-guiding device having a light-incident surface and a light-outgoing surface for guiding light incident from the light-incident surface from the light-outgoing surface toward a light-receiving surface of a photodetector for generating an electric signal corresponding to a quantity of the received light. The device comprises a hologram layer having an interference pattern which acts as a diffraction grating to diffract and reflect the light, incident from the light-incident surface, in a predetermined direction. The hologram layer is interposed between first and second total reflection layers. The first total reflection layer has a first total reflection surface disposed in opposed relation to one of the longitudinal surfaces of the hologram layer so that the light diffracted and reflected by the hologram layer is incident on the first total reflection surface at a predetermined angle larger than the critical angle so as to be total-reflected thereon, and the second total reflection layer has a second total reflection surface disposed in opposed relation to the other longitudinal surface of the hologram layer so that the incident light passing through the hologram layer is incident on the second total reflection surface at a predetermined angle greater than the critical angle so as to be total-reflected thereon. This arrangement improves the light-receiving performance concurrently with reducing the thickness of the device.

Light-guiding device having a hologram layer

Growing community of inventors

Kariya, Japan

Shinji Namba