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. 06, 2015
Filed:
Mar. 05, 2012
Applicant:
Yukinobu Tanaka, Tokyo, JP;
Inventor:
Yukinobu Tanaka, Tokyo, JP;
Assignee:
Hitachi Consumer Electronics Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/00 (2006.01); G11B 7/085 (2006.01); G11B 7/09 (2006.01); G11B 7/095 (2006.01); G11B 7/1275 (2012.01); G11B 7/1392 (2012.01);
U.S. Cl.
CPC ...
G11B 7/08505 (2013.01); G11B 7/0938 (2013.01); G11B 7/0953 (2013.01); G11B 7/0956 (2013.01); G11B 7/1275 (2013.01); G11B 7/13925 (2013.01); G11B 2007/0013 (2013.01);
Abstract
There is a problem that when the relative angle between laser light and an optical disc is changed by temperature, or a chucking state of an optical disc and so forth, the formerly recorded data is overwritten. The above-mentioned problem is solved by performing focus control and tracking control independently with respect to a servo layer and a recording layer in a grooveless disc.