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:
Nov. 10, 1998
Filed:
Jun. 10, 1996
Moritoshi Miyamoto, Kawasaki, JP;
Kengo Emoto, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical information recording and/or reproducing apparatus for radiating a plurality of beams to an optical information recording medium to record information in the optical information recording and/or reproduce information recorded therein. The apparatus includes (i) an irradiation optical system, (ii) a diffraction grating for splitting a beam from the irradiation optical system into a plurality of beams, the diffraction grating having a plurality of different diffraction regions formed without overlapping with each other, the plurality of beams split by the plurality of diffraction regions being guided onto the optical information recording medium, and (iii) a detection optical system for detecting a beam from the optical information recording medium. The detection optical system includes a photodetector which includes a plurality of light receiving elements in which at least three light receiving elements are provided on a predetermined arrangement line and at least two light receiving elements are arranged so as to sandwich the arrangement line therebetween.