| 摘要 |
PURPOSE:To eliminate the need for an outer peripheral mask at the time of production of an optical disk and to prevent the change in the characteristics of the optical recording medium in the outer peripheral part and the corrosion from the outer peripheral part. CONSTITUTION:The surface between the film forming surface and outer peripheral end face 6 of an optical disk substrate 2 is chamfered to provide a round part. A projection 12 facing the outer peripheral end face is provided to suppress the incidence of the recording particles of the optical medium to the outer peripheral end face 6. The radius of curvature of the round part is specified to 0.4 to 1.2mm. |
