| 摘要 |
PROBLEM TO BE SOLVED: To make the cycle characteristics of an optical disk better, the mass production cost lower and the film thickness distribution more uniform. SOLUTION: In the phase change optical disk provided, successively from the incident side of a laser beam, with a protective layer, intermediate layer, first dielectric layer, recording and reflection layer, d1<100 nm and d1+d2>100 nm, d1>=d2, n2<=b3+0.4 and k2<=k3+0.2 when the wavelength of the laser beam for recording and reproducing the phase transition optical disk is defined as λ1, the refractive index at the wavelength λ1 of the intermediate layer as n2, the attenuation coefficient as k2, the film thickness as d2 (nm), the refractive index at the wavelength λ of the protective layer as n3, the attenuation constant as k3 and the film thickness of the first dielectric layer as d1 (nm). |
