OPTICAL DISK SUBSTRATE, OPTICAL DISK, AND MANUFACTURE OF OPTICAL DISK SUBSTRATE

摘要

PROBLEM TO BE SOLVED: To make transferrable a tracking guide groove and a pre-pit by making the surface of a pre-pit part of an optical disk master disk a reference, using the optical disk master disk with different depth of an inner peripheral part surface and an outer peripheral part surface and forming the optical disk substrate. ;SOLUTION: When laser cutting is performed, by opening-limiting the inner peripheral side of the pre-pit part to be cut, or by changing the guide groove and an aperture of a lens when a pre-pit cutting is performed, a photoresist recording master disk of a structure that the inner peripheral side surface is lower than the outer peripheral side surface for the pre-pit part is formed. This stamper 34 is fitted to a movable die 33, and based on a relation among compression pressure of an injection compression process, the viscosity of a fused polycarbonate resin 36 and the height of the pre-pit part, the fused polycarbonate 36 is molded to form an optical disk master disk having a difference between the land part of the inner peripheral side of the pre-pit part and the land part of the outer peripheral side, and a storage reproducing characteristic is improved.;COPYRIGHT: (C)2000,JPO