CD-ROM with machine-readable I.D. code

• US 5,400,319 A
• Filed: 10/06/1993
• Issued: 03/21/1995
• Est. Priority Date: 10/06/1993
• Status: Expired due to Term

• Current Assignee: Digital Audio Disc Corporation (Sony Group Corp.)
• Original Assignee: Digital Audio Disc Corporation (Sony Group Corp.)
• Inventors: Mitchell, Michael L., Kunz, Russ A., Brannon, Clifford R., Fite, Barry A.
• Primary Examiner(s): LaRoche, Eugene R.
• Assistant Examiner(s): Nguyen, Tan
• Application Number:
  US08/132,709
• Time in Patent Office: 531 Days
• Field of Search: 369/275.2, 369/275.5, 369/283, 369/52, 369/53, 369/54, 369/286, 369/292, 346/76 L, 380/3, 380/4
• US Class Current: 369/275.5
• CPC Class Codes: G06F 21/00 Security arrangements for protecting computers, components thereof, programs or data against unauthorised activity
• CPC Class Codes: G06K 1/126 by photographic or thermographic registration recording apparatus for measuring instruments G01D15/00
• CPC Class Codes: G06K 19/14 the marking being sensed by radiation
• CPC Class Codes: G11B 20/00086 Circuits for prevention of unauthorised reproduction or copying, e.g. piracy indicating unauthorised use of record carriers in general G11B23/28; scrambling for television signal recording H04N5/913; network architectures or network protocols for network security H04L63/00; cryptographic mechanisms or cryptographic arrangements for secret or secure communication H04L9/00
• CPC Class Codes: G11B 20/00115 wherein the record carrier stores a unique medium identifier
• CPC Class Codes: G11B 20/00123 the record carrier being identified by recognising some of its unique characteristics, e.g. a unique defect pattern serving as a physical signature of the record carrier
• CPC Class Codes: G11B 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00246 wherein the key is obtained from a local device, e.g. device key initially stored by the player or by the recorder
• CPC Class Codes: G11B 20/0026 the key being stored as a barcode
• CPC Class Codes: G11B 20/00326 the key being embossed on the record carrier
• CPC Class Codes: G11B 20/00557 wherein further management data is encrypted, e.g. sector headers, TOC or the lead-in or lead-out areas
• CPC Class Codes: G11B 20/00695 said measures preventing that data are read from the recording medium
• CPC Class Codes: G11B 20/00876 wherein physical copy protection means are attached to the medium, e.g. holograms, sensors, or additional semiconductor circuitry
• CPC Class Codes: G11B 20/00927 wherein said defects or errors are generated on purpose, e.g. intended scratches
• CPC Class Codes: G11B 23/281 by changing the physical properties of the record carrier
• CPC Class Codes: G11B 23/284 on the record carrier
• CPC Class Codes: G11B 23/36 Signals on record carriers or on containers and recorded by the same method as the main recording
• CPC Class Codes: G11B 23/38 Visual features other than those contained in record tracks or represented by sprocket holes the visual signals being auxiliary signals
• CPC Class Codes: G11B 27/105 of operating discs
• CPC Class Codes: G11B 27/24 by sensing features on the record carrier other than the transducing track ; sensing signals or marks recorded by another method than the main recording
• CPC Class Codes: G11B 7/0037 : with discs
• CPC Class Codes: G11B 7/005 : Reproducing G11B7/0065 takes precedence
• CPC Class Codes: G11B 7/24 : Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the arrangement of information on the carrier G11B7/007
• CPC Class Codes: G11B 7/26 : Apparatus or processes specially adapted for the manufacture of record carriers

Abstract

A machine-readable serial number is formed on a CD-ROM by using a laser to selectively remove a reflective layer from the CD-ROM. Removal of the reflective layer creates defects in addressable information storage locations on the CD-ROM. The serial number is read by detecting the defects. The serial number is used in a software distribution system in which many different software programs are distributed on a single CD-ROM and an access code based on the desired software program and the serial number of a particular CD-ROM is used to "unlock" the desired program on the particular CD-ROM.

Claims

1. A method of forming a machine-readable code on an optical information storage disk, comprising the steps of:

forming a disk shaped molded substrate which includes an information recording area in which information is represented by pits formed in said information recording area;

applying a reflective coating to said information recording area of said substrate; and

removing said reflective coating from selected portions of said information recording area to form a code pattern.

2. A method according to claim 1;

wherein said removing step includes applying a laser beam to a surface of said disk to vaporize portions of said reflective coating.

3. A method according to claim 2;

wherein said removing step includes removing said reflective coating in a plurality of bands, each of said bands extending in parallel to the other bands in a circumferential direction on said disk.

4. A method according to claim 3;

wherein information is recorded in tracks in said information recording area, said tracks having a track pitch, said bands being substantially wider than said track pitch.

5. A method according to claim 4;

wherein said bands are at least ten times wider than said track pitch.

6. A method according to claim 3;

wherein said removing step includes applying said laser beam at predetermined locations along a radius of said disk with said disk at rest to form respective portions of said bands, rotating said disk by a small amount and again applying said laser beam at predetermined locations along another radius of said disk with said disk at rest to form additional respective portions of said bands.

7. A method according to claim 6;

wherein said rotation of said disk by a small amount and said formation of said additional respective portions of said bands are each performed a plurality of times.

8. A method according to claim 7;

wherein said plurality of times is at least 50 times.

9. A method according to claim 6;

wherein said small amount by which said disk is rotated is in the range of 5-100 microns in a circumferential direction of said disk at a radial position of at least one said bands.

10. A method according to claim 1;

further comprising the step of applying a protective layer upon said reflective coating applied to said substrate.

11. A method according to claim 10;

wherein said removing step is performed before said step of applying a protective layer.

12. A method according to claim 10;

wherein said removing step is performed after said step of applying a protective layer.

13. An apparatus for forming a machine-readable code pattern on a prerecorded compact disk that includes a reflective coating on an information bearing substrate, said information bearing substrate having an information recording area for storing information in recording tracks, the apparatus comprising:

means for rotating said disk about a center of rotation of said disk;

a laser for selectively emitting a cutting beam;

means for directing said cutting beam to a point on said disk at a selected distance from said center of rotation of said disk; and

means for controlling said laser and said means for directing so as to remove said reflective coating from selected portions of said information recording area of said information bearing substrate to form said machine-readable code.

14. An apparatus according to claim 13;

wherein said laser and said means for directing are controlled to remove said reflective coating in a plurality of bands, each of said bands extending in parallel to the other bands in a circumferential direction.

15. An apparatus according to claim 14;

wherein said recording tracks in which information is recorded on said information bearing substrate have a track pitch, said bands being substantially wider than said track pitch.

16. An apparatus according to claim 15;

wherein said bands are at least ten times wider than said track pitch.

17. An apparatus according to claim 13;

wherein said means for directing includes means for deflecting said cutting beam to selected positions along an axis that substantially coincides with a radius of said disk.

18. An apparatus according to claim 17;

wherein said means for deflecting includes a rotating mirror.

19. An optical information storage disk in which a reflective coating is formed on a molded information bearing substrate, said information bearing substrate having an information recording area for storing information in recording tracks, and wherein said reflective coating is removed in a predetermined pattern from selected portions of said information recording area of said substrate to form a machine-readable code.

20. An optical information storage disk according to claim 19 in which computer software is stored.

21. An optical information storage disk according to claim 19;

wherein said predetermined pattern is formed of a plurality of bands extending in parallel to each other in a circumferential direction of said disk.

22. An optical information storage disk according to claim 22;

wherein all of said bands are of substantially the same width.

23. A method of forming a machine-readable code on an optical information storage disk comprising the steps of:

forming a plurality of addressable information storage locations on said disk, at least some of said locations containing program information; and

creating defects in ones of said information storage locations in a predetermined pattern to form a machine-readable code.

24. A method according to claim 23;

wherein said disk is a compact disk formed of a molded substrate and a reflective coating on said substrate, said substrate storing said program information in the form of pits molded in said substrate, and said step of creating defects includes removing said reflective coating from said substrate at said ones of said information storage locations.

25. A method according to claim 24;

wherein said removing includes vaporizing said reflective coating with a focused laser beam.