CD recording device and method and CD

Abstract

In apparatus for recording on a compact disc (1), sub-data strings are recorded so that the main data strings are reproducible by an optical pickup (13) for reproducing the main data strings, and the main data strings are protected from being copied illegally without any adverse effect on reproduction of the pit-and-land main data strings. The sub-data string (ED) is recorded by locally changing the reflectance of the reflection film in the form of irregularities such as pits or marks at a timing which does not affect the position information of the edge.

Description

technical field [0001] The present invention relates to an optical disc recording apparatus, an optical disc recording method, and an optical disc, and is applicable to, for example, an apparatus for recording on one or more compatct discs and an optical disc player. In the present invention, the sub-data string is recorded by locally changing the reflective film on the disc on which information has been recorded in the form of pit strings in advance. Since the sub-data string is recorded, it is used to reproduce the main data. The optical pickup of the string can reproduce the main data string and it is difficult to illegally copy the main data string without any adverse effect on reproduction of the main data string in the pit string form. Background technique [0002] So far, in the process of recording data on the optical disc, the data string to be recorded must undergo data processing and then undergo EFM modulation (0-14 modulation) to form a pit string with a time pe...

AI Technical Summary

Problems solved by technology

Although, making such a mark can make it intuitively understandable, the optical pickup of the CD player does not reproduce this mark

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