| 摘要 |
PURPOSE: To provide a phase change type optical disk capable of corresponding even to a digital video disk and wide in a adaptation range of linear speed. CONSTITUTION: An optical data recording medium is constituted by successively laminating a first protective layer 3 with a thickness of 90-120nm composed of a transparent dielectric, a recording layer 4 with a chickness of 15-30nm, a second protective layer 5 with a thickness of 5-25nm composed of a transparent dielectric, a reflecting layer 6 with a thickness of 50-150nm composed of a metal or an alloy thereof and an UV cured resin protective layer 7 with a thickness of 5μm or more on a light pervious substrate 2. The recording layer 4 consists of at least three elements of Ge, Sb and Te and is constituted so as to become a compositional ratio of Ge: 16-20 atomic %, Sb: 20-34 atomic % and Te: 50-60 atomic %. When recording, reproduction and erasure direct overwriting are performed, a laser beam spot is allowed to scan on the recording layer within a linear velocity range of 2.0-6.0m/s. |
