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

  • US 5,703,858 A
  • Filed: 10/21/1996
  • Issued: 12/30/1997
  • Est. Priority Date: 01/23/1995
  • Status: Expired due to Term
First Claim
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1. A device for forming a glass master to inhibit manufacture of a counterfeit optical CD-ROM, wherein said device is used in conjunction with a mastering system having an input source for providing data to be recorded on said glass master and a recorder for forming said glass master in accordance with a received signal, comprising:

  • a signal source for providing a random high frequency signal for forming a first defect in said glass master;

    a switch for electrically connecting said recorder to said signal source; and

    a central processor unit (CPU) for controlling said switch to electrically connect said signal source to said recorder to form said first defect at a selected address of said glass master wherein said first defect causes generation of a predetermined error signal in a CD-ROM manufactured from said glass master.

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