Hologram scanner

Abstract

Abstract PURPOSE:To prevent the degradation of the light use efficiency due to the fall of the space frequency by giving a double hologram structure to a light deflecting disc which is rotated to scan and condense a light while a reproducing beam is made incident on the center part. CONSTITUTION:A light deflecting disc 20 is a single facet having the double structure of holograms 21 and 22, and an incident light 25 is made incident from the center of the disc 20 and is diffracted to become a scanning light 25. A refocused light 27 reflected on a bar code is diffracted and condensed by holograms 21 and 22 again and is made incident on a photodetector 28 to read information. Since the double hologram structure is given to the light deflecting disc 20, the use efficiency of light is good, and the diameter of the disc is made smaller, and a lens system for condensing the refocused light is unnecessary, and the device is made small-sized.

Inventors

• 👤 Fumio Yamagishi
• 👤 文雄 山岸
• 👤 Kozo Yamazaki
• 👤 行造 山崎
• 👤 Hiroyuki Ikeda
• 👤 池田　弘之
• 👤 Yushi Inagaki
• 👤 雄史 稲垣

Bibliographic Details