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. 21, 1991
Filed:
Jan. 31, 1989
Applicant:
Inventors:
Gohji Uchikoshi, Higashimurayama, JP;
Toshiko Otomo, Tokyo, JP;
Assignee:
Nakamichi Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ;
U.S. Cl.
CPC ...
369 44250 ; 369 4434 ; 369 4435 ; 369 54 ;
Abstract
A signal processing circuit for an optical disk apparatus to detect a sine wave tracking error signal obtained when an optical spot on an optical disk moves in a direction of a radius of the optical disk and a sine wave whole reflection light quantity signal having a component of phase offset by 90 degrees relative to that of the tracking error signal and to deform the sine wave whole reflection light quantity signal so that a deformed signal is provided which has states of 'H' and 'L' selected on timing when the whole reflection light quantity signal traverses a center level of its amplitude.