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:
Apr. 19, 2005
Filed:
Nov. 13, 2001
Applicants:
Tetsuya Shiizaki, Hirakata, JP;
Saburo Kubota, Katano, JP;
Katsuhiro Kida, Suita, JP;
Inventors:
Assignee:
Matsushita Electric Industrial Co., Ltd., Osaka-Fu, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G11B007/24 ;
U.S. Cl.
CPC ...
Abstract
An RF signal is read from a rewritable DVD while rotating the rewritable DVD. The read RF signal is converted to pulse signals according to different threshold values, and the number of pulses of each pulse signal is counted. Indexes IBSmin, IBMmax, IBS, and IBRmax are determined from the relationship between the counted numbers and the threshold values, and the recording quality of the BCA on the rewritable DVD is evaluated by judging whether these indexes satisfy the following inequalities:max/min≦0.8max/≦1.5