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. 12, 2014
Filed:
May. 17, 2013
Applicants:
Hitachi Consumer Electronics Co., Ltd., Tokyo, JP;
Hitachi-lg Data Storage, Inc., Tokyo, JP;
Inventor:
Atsushi Kikugawa, Tokyo, JP;
Assignees:
Hitachi Consumer Electronics Co., Ltd., Tokyo, JP;
Hitachi-LG Data Storage, Inc., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G11B 7/24 (2013.01);
U.S. Cl.
CPC ...
Abstract
In the land-groove method, wobble interference is reduced. STW modulation is used as wobble modulation for a part where wobble interference can occur, for example, a part where the configurations of both side walls of the groove are not the same and groove width modulation is unavoidable. Thereby, the amplitude of the groove width modulation can be suppressed to a quarter of that when BPSK modulation is used.