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:
May. 14, 1996
Filed:
Jan. 18, 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 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 from the recording medium and for generating a tracking error signal indicative of a positional deviation between a light beam irradiated position and a track, a tracking actuator for moving the objective lens in a direction intersecting tracks of the recording medium, a tracking controller for driving the tracking actuator in accordance with the tracking error signal so as to correct the positional deviation, a position detector for detecting a relative position of the objective lens with respect to the optical head in the direction intersecting the tracks, a measuring device for measuring a relationship between an offset of the tracking error signal and a position of the objective lens from the tracking error signal and an output of the position detector, a memory for storing the relationship measured by the measuring device and a correction device for correcting the offset of the tracking error signal in accordance with the stored relationship, in response to the position detector output signal.