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. 01, 2008
Filed:
Sep. 09, 2004
Applicants:
Yasuaki Maeda, Kanagawa, JP;
Masahiro Shigenobu, Kanagawa, JP;
Inventors:
Yasuaki Maeda, Kanagawa, JP;
Masahiro Shigenobu, Kanagawa, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 20/18 (2006.01);
U.S. Cl.
CPC ...
Abstract
The present invention relates to a skew control method and a skew control unit by which stable skew control can be performed with a simple configuration without the need for a dedicated skew sensor. Focus drive voltages Vand Vare measured at a plurality of points Pand Pset by moving an optical pick-upin the radial direction of an optical discin a state where a focus servo of the optical pick-upis ON, and skew angle control is performed so that Vand Vare equal to each other.