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. 02, 1995
Filed:
Aug. 12, 1994
Applicant:
Inventors:
Toshihisa Deguchi, Nara, JP;
Tetsuya Inui, Nara, JP;
Kenji Ohta, Nara, JP;
Shohichi Katoh, Yamatokoriyama, JP;
Assignee:
Sharp Kabushiki Kaisha, Osaka, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 4432 ; 369 4437 ; 369 4441 ;
Abstract
A tracking system for positioning a light spot onto a magneto optic or optical disc having a beam guide track preformatted thereon comprises a main light beam and two auxiliary light beams, and a circuit for subtracting a low frequency component of a difference between the tracking error signals, detected by the respective auxiliary light beams and the main light beam, from a tracking error signal detected by the main light beam.