| 摘要 |
<P>PROBLEM TO BE SOLVED: To obtain an optical disk which can record individual ID data on the disk with signal recording layers having a ≥2 layer structure. <P>SOLUTION: The optical disk constituted by superposing ≥2 layers of semitransmission reflection films and total reflection films forming a light reflection film for reading signals out of the signal recording layer by laser light is so constituted that the external diameter of the semitransmission reflection film is smaller than the external diameter of the total reflection film, the reflection film material used for the total reflection film 6 varies in an inner peripheral part region and outer peripheral part region, the inner peripheral part region is a reflection film region 7 for recording the signals, the outer peripheral part region is a region 8 for recording an identification ID code, and the region 8 for recording the identification ID code does not overlap on the semitransmission reflection film. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
