| 摘要 |
PROBLEM TO BE SOLVED: To realize satisfactory reproducing characteristics in all information holding layers, in a multi-layered information medium having the plural information holding layers, and to obtain satisfactory mechanical accuracy in the multi- layered information medium. SOLUTION: The optical information medium has at least two layers of annular information holding layers which hold recording information and/or servo-information on a disk-shaped substrate having a center hole or between a pair of disk-shaped substrates. In the information holding layers, the information holding layer exists which performs recording or reproduction by means of recording light or reproducing light transmitted through other information layers. And, the optical information medium has at least two annular resin layers having an annular projecting part in an inner peripheral edge and the resin layer are laminated in a step shape so as not to cover the annular projecting part of other resin layers. |
