| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a disk like information recording medium by which unauthorized reproduction of principal information formed by unduly copying principal information such as digital AV content information can be strongly prevented to a conventional reproducing device and as a result unauthorized copy of principal information can be strongly prevented, considering public discussion of unauthorized copy of a digital AV content since recordable mediums each having reproduction compatibility of the same capacity and the same signal format with an original information recording medium are supplied inexpensively and in a large amount. <P>SOLUTION: A strong unauthorized copy preventing effect is realized by recording the digital AV content being the principal information and decoding information needed for normally reproducing the digital AV content in respectively different layers in the same recording medium. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
