MANUFACTURING PROCESS OF ORIGINAL DISC FOR PRODUCING OPTICAL DISC AND PRODUCTION PROCESS OF OPTICAL DISC

摘要

A process for manufacturing an original disc comprising a step for irradiating an inorganic resist layer formed on a substrate with a recording laser beam modulated by an information signal corresponding to the information signal of an information irregular pattern to be formed on an optical disc thus forming an exposure pattern corresponding to the information irregular pattern of the optical disc, and a step for developing the inorganic resist layer to form an irregular pattern corresponding to the information irregular pattern by the inorganic resist layer. In order to manufacture an original disc having an appropriate irregular pattern, the exposed part is irradiated with an evaluation laser beam in the exposure step following trial exposure of the non-recorded region of the resist layer. Recording signal characteristics of the resist layer is then evaluated from the reflected light and an optimal focus position of laser beam for subsequent recording is determined based on the evaluation results.