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:
Jul. 02, 1996
Filed:
May. 23, 1995
Osamu Koyama, Kawasaki, JP;
Tadashi Kato, Kawasaki, JP;
Masayuki Usui, Yokohama, JP;
Yoshihiko Watanabe, Yokohama, JP;
Hisatoshi Baba, Yokohama, JP;
Hirotake Ando, Tokyo, JP;
Hideo Nakajima, Yokohama, JP;
Shinji Sakai, Yokohama, JP;
Kenji Tamaki, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An optical information processing apparatus and method of correcting an offset of a tracking error signal. The apparatus includes an optical head for irradiating a light beam onto an optical recording medium, an objective lens, mounted on the optical head, for condensing the light beam onto the recording medium, a photodetector for receiving a light beam reflected by or transmitted through the recording medium and for generating a tracking error signal indicative of a positional deviation between the light beam irradiated position and a track, a tracking actuator for moving the objective lens in a direction intersecting the tracks and for causing the objective lens to vibrate in the vicinity of the center of the light beam, a tracking controller for driving the tracking actuator in accordance with the tracking error signal so as to correct the positional deviation, a measuring device for measuring an offset of the tracking error signal from an output of the photodetector when the objective lens is caused to vibrate in the vicinity of the center of the light beam and a correction device for correcting the offset of the tracking error signal on the basis of the offset measured by the measuring device.