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. 10, 2004
Filed:
Jun. 06, 2001
Sony Corporation, Tokyo, JP;
Abstract
An optical disk apparatus for recording information of copyright on an optical disk where desired data are recorded by repetition of pits or marks. The apparatus comprises a recording means for recording the copyright information by irradiating a laser beam onto the optical disk in such a manner as to repeatedly form, in a predetermined area of the optical disk, local regions which cause greater changes in the return-light receiving result as compared with the pits or marks. On the optical disk, the existence ratio of the local regions for recording the copyright information is set to be less than 0.3 in the circumferential direction of the disk. In a reproduction mode, the copyright information recorded like a bar code for example can be exactly reproduced with certainty.