| 摘要 |
PROBLEM TO BE SOLVED: To provide an information recording disk having the recording areas of two types of recording densities. SOLUTION: The information recording disk is provided with a signal recording surface having a first area 4 and a second area 6 sequentially divided outward from a center hole 2 in a radial direction. The incident optical path surfaces of a reproducing light for reading-out from the first area and a reproducing light for reading-out from the second area are set to be opposite each other. Thus, the information recording disk is provided with the recording areas of two types of recording densities. |
