Optical recording medium and the reproducing apparatus for the optical recording medium

• US 5,538,773 A
• Filed: 06/28/1994
• Issued: 07/23/1996
• Est. Priority Date: 06/30/1993
• Status: Expired due to Fees

• Current Assignee: Victor Company of Japan Limited (JVC Kenwood Corporation)
• Original Assignee: Victor Company of Japan Limited (JVC Kenwood Corporation)
• Inventors: Kondo, Tetsuya
• Primary Examiner(s): Ryan, Patrick J.
• Assistant Examiner(s): MULVANEY, ELIZABETH EVANS
• Application Number:
  US08/267,167
• Time in Patent Office: 756 Days
• Field of Search: 428/64, 428/65, 428/913, 428/64.1, 428/64.2, 428/64.4, 369/272, 369/273, 369/275.1, 369/275.4, 369/275.5, 369/277, 430/270, 430/495, 430/945
• US Class Current: 428/64.1
• CPC Class Codes: G06F 2211/007 Encryption, En-/decode, En-/decipher, En-/decypher, Scramble, (De-)compress
• 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 20/0021 involving encryption or decryption of contents recorded on or reproduced from a record carrier
• CPC Class Codes: G11B 20/00253 wherein the key is stored on the record carrier
• 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 7/005 Reproducing G11B7/0065 takes precedence
• CPC Class Codes: G11B 7/26 Apparatus or processes specially adapted for the manufacture of record carriers
• CPC Class Codes: Y10S 428/913 Material designed to be responsive to temperature, light, moisture
• CPC Class Codes: Y10S 430/146 Laser beam
• CPC Class Codes: Y10T 428/21 Circular sheet or circular blank

Abstract

The present invention discloses an optical recording medium having copy protection measures, production method thereof and a reproducing apparatus therefor. The optical disc comprises a data recording area recorded with ciphered digital signals and a cipher key information recording area provided other than the data recording area in the optical recording medium for recording cipher key information to determine a deciphering method of the ciphered digital signals. The cipher key information is provided along a peripheral edge surface which is outside the surface of the optical recording medium in a serrated pattern, perpendicular to the surface having the recording layer. The serrated pattern is formed by an injection molding machine using a metal mold having an injection molding member provided with a serrated negative pattern in accordance with the recording cipher key information to be recorded. The ciphered digital signals and the cipher key information are respectively read out from the optical recording medium by a reproducing device and the ciphered digital signals obtained are deciphered by a deciphering device using the cipher key information obtained.

Claims

1. An optical recording medium comprising:

a data recording area recorded with ciphered digital signals; and

a cipher key information recording area provided other than the data recording area in the optical recording medium and recorded with cipher key information which determines a deciphering method of the ciphered digital signals recorded on the data recording area, the cipher key information being provided along outside surface of the medium perpendicular to the surface having the recording layer of the optical recording medium.

2. An optical recording medium as claimed in claim 1, wherein the cipher key information is formed in a serrated pattern having a plurality of notches and ridges, and a difference of a height from each of bottoms of the notches to each of tops of the ridges is limited less than or equal to 300 μ

m.

3. A reproducing apparatus for reading out an original data from an optical disc having a data recording area recorded with ciphered digital signals and a cipher key information area recorded with cipher key information, the cipher key information being formed at outside surface of the medium perpendicular to the surface having the recording layer of the optical disc, outside surface of the medium perpendicular to the surface having the recording layer being formed other than the data recording area of the optical disc, the reproducing apparatus comprising:

data reading means for reading out the ciphered digital signals from the data recording area;

a cipher key information reading means provided so as to face outside surface of the medium perpendicular to the surface having the recording layer of the optical disc for reading out the cipher key information;

deciphering means for deciphering the ciphered digital signals and restoring the original data by using the cipher key information obtained with the cipher key information reading means.