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. 31, 2005
Filed:
Apr. 12, 2001
Applicants:
Koichi Morioka, Katano, JP;
Takashi Yumiba, Uji, JP;
Keiichi Kawashima, Hirakata, 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 optical disc includes a processed area that has been processed by the irradiation of a YAG laser. Concave pits and convex pits having a length 3T-14T (T=0.133 μm) are formed in an area of the optical disc other than the processed area. The processed area includes (1) a concave pit having a length X or (2) a pit string that has a length X and includes a convex pit from which a reflection layer has been removed. A specific area of the optical disc records physical character information that shows the location and length of the concave pit or the pit string in the processed area.