| 摘要 |
PURPOSE:To obtain a substrate for an optical disk without having a groove at an inner periphery by providing a recessed part in which a presser part fits in a stamper, and setting the stamper and a part confronting with the molding vacancy of the presser part so as to be positioned at almost the same plane. CONSTITUTION:Disk shape molding vacancy are formed in molding dies 1 and 2, and the stamper 16 is placed on a plane confronting with the molding plane of the molding die 1 via a mirror plate 5, and the stamper 16 is pressed and fixed on the die 1 by an inner ring 17 and an outer ring 8. And a step A is provided at the inner peripheral part of the stamper 16, and the inner ring 17 fixes the stamper 16 by fitting in the step A, and is constituted so that the stamper 16 and the part confronting with the molding vacancy of the inner ring 17 can be positioned at almost the same plane. In such a way, it is possible to obtain the substrate for the optical disk without having the groove at the inner periphery. |
