| 摘要 |
PURPOSE:To provide the material for a substrate reflection layer which enables a high reflectivity by imparting a good push-pull signal characteristic to an optical disk having the film of the material for the substrate reflection layer which exhibits a high reflectivity and high transmittance with a good balance on the substrate. CONSTITUTION:The substrate reflection layer 2, then a recording layer 3 are formed on the substrate 1 and light is made incident from the substrate 1. Grooves 4 for tracking servo are directly formed on this substrate 1. The substrate 1 consists of an acrylic resin, polycarbonate resin, glass, etc. The film formation of the reflection layer 2 is executed by a sputtering method, vacuum vapor deposition method, etc. Further, the material to be used for the recording layer 3 generates a certain optical change by the photon energy or thermal energy generated by photoirradiation. Namely, a change in the reflectivity or transmittance arises from a color change, phase change, pit formation, shape change, etc. As a result, the high reflectivity is enabled. |
