| 摘要 |
PURPOSE: To attain a high density recording by effectively using the margin of track recording in an inner peripheral part by narrowing the pitch of an information signal sequence in the inner peripheral part than the pitch in the outer peripheral part in an information recording layer. CONSTITUTION: An information area Aw as an information recording region is divided into a first recording area Aw1 and a second recording area Aw2 from the inner peripheral side. The information area Aw is formed in a range between a radius of >=24mm and a radius of <58mm from the central point 0. In this case, the first recording area Aw1 is formed in a range between the radius of >=24mm and a radius of <40mm and the second recording area Aw2 is formed in a range between the radius of >=40mm and the radius of <58mm. In this optical disk, the track pitch in the first recording area Aw1 is set, for instance, to 0.80μm and the track pitch in the second recording area Aw2 0.85μm. |
