| 摘要 |
PURPOSE:To strengthen an optical disk against flows and defects and, at the same time, accurately detect positions of sectors, by installing plural sector areas and sector separating information areas in guide tracks. CONSTITUTION:At a surface R side of an optical disk 1, concentric or spiral giode tracks 2a-2e are formed by grooves having a width of (w), a pitch of (pt), and a depth of (delta), and each track is separated from each other by flat parts 3a-3d between the grooves. A very small spot light 5 is irradiated on a recording layer 4 from the surface side of a substrate 6 and the light focused on the surface R, and then, information is recorded on the bottom part of the tracks 2a-2e. Address information representing the address of the tracks is recorded in address areas A1 and A2 by an uneven phase groove structure, and they are cut in a point symmetry about the center O of the disk 1. Moreover, the tracks 2a-2e are divided into plural sector areas S1-S32 by sector separating information areas B1-B32 and information is recorded in the sector areas. |
