Optical pickup

Abstract

Abstract PURPOSE:To miniaturize an optical disk memory device and to shorten the access time by using a hologram in the principal part of an optical pickup to contrive the miniaturization of the optical pick-up and the reduction of the weight. CONSTITUTION:The optical pickup consists of an element 3 where two holograms 31 and 34, two holographic gratings 32 and 33, and a quarter-wave plate 15 are laminated, a light source 11 which emits a coherent light, and a photodetector 18 which detects a signal light. The collimated light going from the light source LD 11 to a point T and the reflected signal light going from the point T to the photodetector 18 are separated from each other by the element 3, and an optical lens, a prism, a polarizing beam splitter, etc., consisting of a glass in the optical pickup are substituted with holograms formed with very thin films. As the result, the optical pickup is considerably miniaturized and reduced the weight, and the cost of parts is reduced and the asssembling time is shortened to reduce the cost.

Inventors

• 👤 Masayuki Kato
• 👤 雅之 加藤
• 👤 Fumio Yamagishi
• 👤 文雄 山岸
• 👤 Hiroyuki Ikeda
• 👤 池田　弘之
• 👤 Yushi Inagaki
• 👤 雄史 稲垣

Bibliographic Details