The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 24, 1991
Filed:
Sep. 08, 1989
Naosato Taniguchi, Atsugi, JP;
Kiyonobu Endo, Yokohama, JP;
Tetsuro Kuwayama, Yokohama, JP;
Hiroaki Hoshi, Kawasaki, JP;
Hiroshi Osawa, Atsugi, JP;
Koyo Hasegawa, Tokyo, JP;
Masakuni Yamamoto, Atsugi, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical head device comprises a light source, a light splitter for reflecting a light emitted from the light source by a first plane thereof to direct the light to an information carrier and transmitting the light from the information carrier through the first plane, a photo-detector for detecting the light from the information carrier, and a diffraction grating structure arranged on a second plane of the light splitter for diffracting the light transmitted through the first plane and directing it to the photo-detector.