Patent ID: 6768707
Filing Date: 2004-07-27
Classification: G11B

Abstract:
A phase-change type optical recording medium, comprising:(a) a substrate; (b) a recording layer formed on said substrate, wherein a phase condition of said recording layer being changed when a laser beam is radiated thereonto, to thereby record, erase or reproduce data into or from said recording layer; and (c) a reflection layer formed on said recording layer for reflecting a laser beam having been radiated onto said recording layer, said recording layer being formed so that the following equation (A) is satisfied: Rc>Rm>Raâ€ƒâ€ƒ(A) wherein Rc indicates a reflectivity to be obtained when said recording layer is in crystal condition, Ra indicates a reflectivity to be obtained when said recording layer is in amorphous condition, and Rm indicates a reflectivity to be obtained when said recording layer is in mixed condition of molten condition and crystal or amorphous condition.