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:
Mar. 22, 2011
Filed:
Jan. 21, 2005
Applicant:
Toshihiro Fujiki, Tokyo, JP;
Inventor:
Toshihiro Fujiki, Tokyo, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B 7/00 (2006.01);
U.S. Cl.
CPC ...
Abstract
An optical disc recording apparatus that uses a pseudo-random number sequence for recording auxiliary information, wherein a sequence of data based on auxiliary information is modulated by a signal represented by a combination of a sequence of pseudo-random numbers and a predetermined periodic signal, and recorded traces of the pits or the marks are changed depending on the modulated sequence of data, thereby recording the auxiliary information on the optical disc. By making it difficult to estimate the structure of the sequence of pseudo-random numbers, duplication of an optical disc is hindered.