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:
Jan. 08, 2019
Filed:
Apr. 20, 2016
Applicant:
Sony Corporation, Tokyo, JP;
Inventors:
Noriaki Nishi, Kanagawa, JP;
Kimihiro Saito, Tokyo, JP;
Nobuhiko Ando, Tokyo, JP;
Fumiaki Nakano, Saitama, JP;
Yuuichi Suzuki, Kanagawa, JP;
Hiroaki Nakagawa, Tokyo, JP;
Tetsuya Inoue, Kanagawa, JP;
Yutaka Tentaku, Kanagawa, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/09 (2006.01); G11B 20/10 (2006.01); G11B 7/1381 (2012.01);
U.S. Cl.
CPC ...
G11B 7/0938 (2013.01); G11B 7/0929 (2013.01); G11B 20/10046 (2013.01); G11B 7/1381 (2013.01);
Abstract
A cross section of a luminous flux of returning light from a disc is split into a plurality of regions, and an operation is performed so that a weighting of a light amount of a region which has favorable symmetry in a radial direction and is formed on a circumference of an ellipse among the split regions is increased. Further, a lens shift detection signal is formed, and a lens shift detection signal is canceled from a push-pull signal.