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. 15, 2000
Filed:
Oct. 01, 1998
Baruch Sollish, Emmanuel, IL;
T.T.R. Technologies Ltd., Kfar Saba, IL;
Abstract
A method of authenticating a Compact Disc, to distinguish an original Compact Disc from an unauthorized copy thereof. One or more invalid symbols are written into the subcode of the original Compact Disc, such one affecting the Q-channel, by using special equipment. The Q-channel normally contains only track location information whose format and content are precisely defined by the applicable standards, and thus ordinary consumer Compact Disc recording equipment does not receive external Q-channel input, but rather generates Q-channel data internally when recording. Therefore, invalid symbols affecting the Q-channel of an original Compact Disc cannot be copied by ordinary consumer Compact Disc recording equipment. Consequently, the presence of data in the Q-channel of a Compact Disc serves to distinguish an original Compact Disc from an unauthorized copy thereof. Invalid symbols include both symbols with incorrect values as well as bistable symbols, which cannot be copied by most professional mastering equipment. The present invention discloses methods for reading the Q-channel to determine the presence or absence of predetermined invalid data.