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. 16, 2005
Filed:
Aug. 06, 2001
Applicant:
Yasukiyo Kunimatsu, Kawasaki, JP;
Inventor:
Yasukiyo Kunimatsu, Kawasaki, JP;
Assignee:
Fujitsu Limited, Kawasaki, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B007/005 ;
U.S. Cl.
CPC ...
Abstract
A phase compensation method uses a phase plate to compensate for an optical phase of a reproduced signal in a reproducing optical system which is provided with respect to the reproduced signal from an optical recording medium. The position of the phase plate is controlled within a predetermined variable range depending on a type of the optical recording medium, so that a CNR of a reproduced signal becomes a maximum or, a DC fluctuation of the reproduced signal becomes a minimum or, a crosstalk level from adjacent tracks becomes a minimum.