Optical recording medium including protruding winding parts used as prepits

Abstract

In an optical recording medium wherein grooves or lands formed on the supporting substrate are used for the recording tracks, and wherein prepits are also formed, production of the supporting substrate and high density recording are facilitated. This medium comprises a supporting substrate and a recording layer on the substrate wherein the surface of the supporting substrate on which the recording layer is formed is formed with alternating continuous convex portions and continuous concave portions which are substantially parallel to each other. The adjacent continuous convex portions are connected by bridging convex portions extending in transverse direction, and the bridging convex portion has a planar configuration that its width is minimum at or near the center between the adjacent continuous convex portions. The supporting substrate is produced by using a master disk which has a resist layer formed with mother patterns of each of the continuous convex portions, continuous concave portions, and prepits. In the production of the master disk, the resist layer is intermittently irradiated with one exposure beam, and the area irradiated is used as the mother pattern of the continuous concave portions or convex portions, and the area which was not irradiated is used as the mother pattern of the prepits.

Dependencies are inferred from the claim text.