| 摘要 |
PROBLEM TO BE SOLVED: To provide a phase transition type optical recording medium which is improved in the respective characteristics of recording, erasing and reproducing even when a surface recording density is increased. SOLUTION: A reflective thin film layer 2, a lower protective layer 3, a recording layer 4, an upper protective layer 5 and a reflection layer 6 are laminated on a substrate 1 sequentially from the substrate 1 side. The reflectivity at the recording layer 4 larger in an amorphous state than in a crystalline state. As a result, the energy absorptance to the recording layer 4 with respect to incident light is made larger in an crystalline state than in an amorphous state. Further, the depth of the guide grooves of the substrate 1 is >=100 nm. |
