OPTICAL RECORDING MEDIUM

摘要

An optical recording medium contains a recording layer being composed of a phase-change recording material where at least four elements, Ga, Sb, Sn and Ge are contained and the transfer linear velocity is 20 m/s to 30 m/s , and when the wavelength of a recording/reproducing light is within the range of 650 nm to 665 nm and the recording linear velocity is 20 m/s to 28 m/s, the refractive index Nc and the extinction coefficient Kc in a crystalline state and the refractive index Na and the extinction coefficient Ka in an amorphous state in the recording layer respectively satisfy the following numerical expressions: 2.0 = Nc = 3.0, 4.0 = Kc = 5.0, 4.0 = Na = 5.0, and 2.5 = Ka = 3.1, and information is recordable at the range of 20 m/s to 28 m/s of recording linear velocity.