OPTICAL DISCS

摘要

A method of manufacturing an optical disc master includes preparing the surface of a glass master plate (2) with an adhesion promoter 4. A photoresist layer (6) is coated on the adhesion promoter (4). This photoresist layer (6) is subjected to a first exposure of a modulated laser beam (8) to produce an exposed photoresist layer (10) corresponding to the modulation information of the laser beam (8). A transparent sheet (16) is placed on the photoresist layer (6). This sheet (16) contains a distinguishing mark to be located in the optical disc. White light (18) from a second light source is passed through the sheet (16) onto the photoresist layer (6) to expose the upper surface of this layer (6). The exposed part of this upper surface provides a pattern (22) corresponding to the mark on the sheet (16). The exposed master plate (2) is then developed to form the pits (12) and a reproduction (24) of the pattern (22). <IMAGE>