| 摘要 |
A disk-shaped optical data carrier having a first surface, a second surface, a CD information layer on which CD-standard data is stored, and a DVD information layer on which DVD-standard data is stored. A first reading light which captures the CD information layer enters the data carrier by the first surface. A second reading light which reads the DVD information layer enters the data carrier by the second surface. The DVD information layer is located approximately in the middle between the first and the second surface. A CD reading light which reads the CD information layer runs through the DVD information layer. The DVD reading light which reads the DVD information layer runs through the CD information layer. |
