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:
Jun. 25, 2013
Filed:
Aug. 04, 2011
Applicant:
Takakiyo Yasukawa, Fujisawa, JP;
Inventor:
Takakiyo Yasukawa, Fujisawa, JP;
Assignees:
Hitachi-LG Data Storage, Inc., Tokyo, JP;
Hitachi Consumer Electronics Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B 20/10 (2006.01);
U.S. Cl.
CPC ...
Abstract
The invention prevents mark distortion during high-speed recording on an optical disc, thereby improving recording performance. A write pulse signal includes mark periods during which marksare formed and space periods during which no marks are formed. Particular mark periods include a top pulsehaving first write power Pw; a bias pulsethat follows the top pulseand has bias power Pm lower than the first write power Pw; and a last pulsethat follows the bias pulseand has second write power Pl lower than the first write power Pw.