Patent ID: 7748050

Claim:
An illegal copy finding system finding an illegal copy of an optical disc on which data and a BCA code are recorded, comprising: a recording apparatus recording on the optical disc the BCA code constituted by a plurality of marks and including a secret code which is modulated in accordance with a previously determined procedure and the secret code forms an undulation with respect to the BCA code in a range capable of recognizing a recording position in a radial direction of the optical disc and a position in a track direction of said plurality of marks as the BCA code; a BCA history database storing a history including a correspondence between the BCA code of the optical disc recording said BCA code and the secret code; and a management center reading the BCA code and the secret code recorded on the optical disc so as to compare both on the basis of an input of the correspondence between the BCA code and the secret code stored in said BCA history database; an optical head irradiating a laser spot light on the optical disc; a BCA code memory for forming the BCA code constituted by a plurality of marks in the track direction by said laser spot light; a secret code memory storing a secret code modulated in accordance with a previously determined procedure in a range capable of recognizing positions in the radial direction of the optical disc and positions in the track direction of a plurality of marks forming the BCA code as the BCA code, with respect to the BCA code stored in said BCA code memory; and a microprocessor controlling the BCA code and the secret code with respect to said optical head output control portion, and wherein said microprocessor constitutes an optical disc manufacturing apparatus or a BCA code recording apparatus which records the BCA code including the secret code on the optical disc surface by modulating the BCA code by using the secret code stored in said secret code memory while moving an optical head in the radial direction of the optical disc.