System for encoding a glass master to enable detection of a counterfeit optical CD-ROM

摘要

A device for enabling detection of a counterfeit optical CD-ROM is disclosed for use in a conventional mastering system. The device includes a signal source for providing a first signal for forming a predetermined defect in a glass master. The device also includes a switch for connecting a recorder of the mastering system to the signal source. In addition, the device includes a decoder for decoding encoded data and address information provided from an input source of the mastering system. Furthermore, the device includes a central processor unit which serves to detect whether a selected address from the decoded data is present. Upon detection of the selected address, the CPU controls the switch to connect the signal source to the recorder to enable the recorder to receive the first signal and form the predetermined defect at the selected address. When a CD-ROM manufactured from the glass master is played back, a desired error signal is generated at the predetermined address indicating that the CD-ROM is not counterfeit. Further, when a counterfeit CD-ROM is played back, the desired error signal is not generated at the predetermined address, thus enabling detection of the counterfeit CD-ROM. In addition, the defect is not visible to the unaided eye when the CD-ROM is viewed.