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:
Dec. 05, 2000
Filed:
Mar. 17, 1998
Applicant:
Inventors:
Yoshizumi Inazawa, Kanagawa, JP;
Tadao Suzuki, Tokyo, JP;
Assignee:
Sony Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G11B / ; G11B / ; H04N / ;
U.S. Cl.
CPC ...
369116 ; 369 54 ; 369 58 ; 369 84 ; 369 47 ; 380201 ;
Abstract
A recording apparatus for modulating a master key used for encrypting main data in a pit-width direction by changing a light amount of a laser beam to then record it on an optical recording medium and records the main data encrypted by using the master key with correcting the main data so as to have a certain pit width and a pit length so that a jitter resulting in intersymbol interference of adjacent pits should be reduced. A reproducing apparatus for reproducing the recorded optical recording medium, and to thereby prevent an optical recording medium from being duplicated by an illegal copy.