Method and apparatus for preventing copying of an optical disk

• US 4,975,898 A
• Filed: 08/18/1988
• Issued: 12/04/1990
• Est. Priority Date: 12/27/1986
• Status: Expired due to Term

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Yoshida, Tadao
• Primary Examiner(s): MCELHENY JR, DONALD E
• Application Number:
  US07/243,035
• Time in Patent Office: 838 Days
• Field of Search: 360/60, 369/100, 369/32, 369/48, 369/49, 369/50, 369/59, 369/13, 369/14, 369/15, 364/286.5, 364/286.6, 380/4
• US Class Current: 369/100
• 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 20/00108 wherein original, non-rewritable record carriers are recognised by trying to erase recorded data
• CPC Class Codes: G11B 20/00659 involving a control step which is implemented as an executable file stored on the record carrier
• CPC Class Codes: G11B 20/00688 said measures preventing that a usable copy of recorded data can be made on another medium
• CPC Class Codes: G11B 20/10 Digital recording or reproducing
• CPC Class Codes: G11B 2020/1259 with ROM/RAM areas
• CPC Class Codes: G11B 7/00745 Sectoring or header formats within a track formats in general G11B20/12

Abstract

A method and apparatus for preventing copying of an optical disk. A software program and the basic data necessary for executing the program, as well as an erasing program are nonrewritably recorded in advance on a predetermined region of the disk. The erasing program attempts to erase the non-rewritable portion, which has no effect on the original disk, but will erase that portion of a disk which is copied. Thus, if the software program and the basic data for executing the program are copied without authorization, the copy disk is prevented from being used.

Claims

1. An optical disk for recording and reproducing data which contains a computer software application program, for use in an optical disk recording and reproducing apparatus, comprising:

a read-only non-erasable portion which contains said computer software application program;

a read and write erasable portion in which data can be recorded;

an erasure program contained in said read-only non-erasable portion which is run when said disk is first read and which instructs said recording and reproducing apparatus to erase any erasable information located in the portion of said disk occupied by said read-only non-erasable portion, such that if said disk is copied onto a read and write erasable disk said computer software application program will be erased upon use of the copied disk.

2. An optical disk according to claim 1 wherein said computer software application program and said erasure program are recorded in said read-only non-erasable portion as physical shape changes on the surface of said portion.

3. An optical disk according to claim 1 wherein said read-only non-erasable portion comprises the inner periphery of said disk.

4. An optical disk according to claim 3 further comprising an index of the contents of said disk which is located inwardly of the inner periphery of said disk.

5. A method of preventing a computer software application program recorded on an optical disk for use in an optical disk reader having a disk controller from being copied, comprising:

recording said computer software application program on a read-only non-erasable portion located on said disk;

recording an erasure program in said read-only non-erasable portion which instructs said recording and reproducing apparatus to erase any erasable information located in the portion of said disk occupied by said read-only non-erasable portion;

instructing said disk controller to run said erasure program when said disk is first read, such that if said disk is copied onto a read and write erasable disk said computer software application program will be erased upon use of the copied disk.

6. A method according to claim 5 wherein said computer software application program and said erasure program are recorded in said read-only non-erasable portion as physical shape changes on the surface of said portion.

7. A method according to claim 5 further comprising locating said read-only non-erasable portion at the inner periphery of said disk.

8. A method according to claim 7 further comprising providing an index of the contents of said disk which is located inwardly of the inner periphery of said disk.