| 摘要 |
PROBLEM TO BE SOLVED: To obtain a phase transition type optical disk which lessens cross erasure and is excellent in repeating characteristics by successively laminating a dielectric layer, lower reflection layer, dielectric layer, recording layer, dielectric layer and upper reflection layer on a substrate and using at least one kind of the metals selected from Au, Al, Ti, Cu and Cr or their alloys for the reflection layer. SOLUTION: The constitution obtd. by successively laminating the dielectric layer 2, the lower reflection layer 3, the dielectric layer 4, the recording layer 5, the dielectric layer 6 and the upper reflection layer 7 on the substrate 1 is adopted for the recording medium 10. The dielectric layer 2 suppresses the thermal deformation of the substrate 1 by heating up of the lower reflection layer 3 at the time of recording. The lower reflection layer 3 acts to suppress the cross erasure by making the absorptance at the time the recording layer 5 is in an amorphous state lower than the absorptance at the time the recording layer is in a crystalline state. Materials or metallic materials having a high refractive index and having a small coefft. attenuation are usable for the lower reflection layer 3. |
