Substrat für optisches Aufzeichnungsmedium und magneto-optisches Aufzeichnungsmedium mit einem solchen Substrat

摘要

The reproduction characteristics, particularly the C/N ratio of a reproduced signal of an optical recording medium are deteriorated by an unevenness or deformation of an optical recording layer due to a convex or concave (i.e. the guide track) configuration of an underlying guide means formed on the surface of the substrate. This deterioration can be prevented by disposing a planalization layer under the recording layer, but the planalization layer lowers the efficiency of the servo tracking. This lowering of servo tracking efficiency is prevented by insertion of a dielectric layer between the planalization layer and the guides.