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:
Aug. 01, 1989
Filed:
Apr. 22, 1987
Osamu Koyama, Kawasaki, JP;
Kazuo Uzuki, Yokohama, JP;
Makoto Shiho, Yokohama, JP;
Shigeru Aoi, Kawasaki, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical information processing apparatus including a light source, a lens system for condensing the light beam emitted from the light source as a minute spot on the track of a recording medium, tracking signal detectors for receiving the light beam from the spot modulated by the recording medium to thereby detect the positional deviation of the spot relative to the track in the tracking direction crossing the track, a correcting device for moving the lens system in the tracking direction in response to the output signal from the tracking signal detectors to thereby correct the positional deviation, and lens position detectors including at least one photoelectric converting element provided outside the effective diameter of the lens system so as to be movable with the lens system, and directly receiving part of the light beam emitted from the light source by the photoelectric converting element to thereby detect the position of the lens system in the tracking direction.