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:
May. 10, 2005
Filed:
Mar. 25, 2002
Narutoshi Fukuzawa, Tokyo, JP;
Syuji Tsukamoto, Tokyo, JP;
Narutoshi Fukuzawa, Tokyo, JP;
Syuji Tsukamoto, Tokyo, JP;
TDK Corporation, Tokyo, JP;
Abstract
A laser beam is directed to an optical recording medium such as a DVD-R to successively form thereon marks of a length corresponding to data with a spacing disposed therebetween. A Q value or the amount of reduction in time causes the rise time of laser irradiation to be delayed with respect to the scheduled rise time at least after a spacing equal in length to the mark of the shortest length employed for recording. The Q value satisfies the following equation (1) expressed in terms of the relationship between the recording speed n and an asymmetry. That is,(0.54×Asymmetry−1.1)/(0.54×Asymmetry−0.1)/  (1)where the asymmetry is the ratio of an amplitude of the shortest mark to that of the longest mark of the recorded marks.