Patent ID: 7200102

Claim:
An optical recording medium provided with a main information area having a laminated thin film layer including an information layer capable of recording an information signal and a subsidiary information area for recording subsidiary information that is different from the information signal, which are divided in one principal plane direction of a substrate, wherein the information layer for recording the information signal in the main information area is provided also in a lead-in area including the subsidiary information area, medium identification information for distinguishing the medium optically by an optical head used for recording the information signal in the information layer of the main information area is recorded in the information layer of the subsidiary information area in the lead-in area with a modulation method that is different from a light beam modulation method used for recording the information signal in the information layer of the main information area, and a plurality of encryption keys used for encrypting an encryption key of the information signal to be recorded in the main information area is provided in an outer periphery of the subsidiary information area in the lead-in area.