| 摘要 |
PURPOSE:To obtain an excellent push-pull signal level, etc., and C/N by specifying the form of a groove and pit on a substrate surface. CONSTITUTION:In a magneto-optical disk which has recessed part forming area having at least erther one of a groove and pit on the surface of a disk shaped substrate and in which recording layers are formed so as to cover the area, the form of at least one of the groove and pit is formed so that relations, theta10>=theta50, theta50>=theta90 are satisfied while derining angles fromed by tangent lines and horizontal lines at positions of 10% depth, 50% depth and 90% depth of recessed part in the side wall of the sectional plane in a substrate radial direction as theta10, theta50, and theta90, respectively. Thus, excellent push-pull signal level, radial contrast and skew margin are obtained and moreover, an excellent C/N is also obtained. |
