| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical disk and a reproducing device capable of obtaining roughly identical reproducing signal characteristics from the substrates of respective layers. SOLUTION: In multi-layer structure optical disk constructed by stacking a plurality of substrates 11 and 12 each having recorded information, when lights are selectively converged in the information recording surfaces of the plurality of substrates 11 and 12 from one surface side, reflected lights from the light converged substrates 11 and 12 are obtained from one surface side. In this case, a reflected light from any one of the light converged substrates 11 and 12 is roughly equal to another while it is obtained from one surface side. |
