| 摘要 |
PURPOSE:To improve recording sensitivity by setting the film thickness of the medium for information recording at such a value at which the wavelength exhibiting the min. value of the reflectivity exists on the shorter wavelength side than the wavelength used for reproducing light in the spectral characteristics of the reflectivity. CONSTITUTION:The film thickness in the amorphous state of the information recording medium 2 of the member for information recording constituted by providing the information recording mdium 2 consisting of one layer on a substrate 1 is set at such a value at which the wavelength exhibiting the min. value of the reflectivity exists on the shorter wavelength side than the wavelength used for reproducing light in the spectral characteristics of the reflectivity. In addition, the information recording medium 2 is constituted of three elements; Sb, Se and Cu. Such recording medium 2 is structurally changed from the amorphous state to the crystalline sate by heating and is thereby so changed as to decrease both the refractive index and attenuation coefft. The wavelength exhibiting the min. value of the reflectivity shifts to the short wavelength side and the high SN is obtd. at the time of recording and reproducing. The improvement in the recording sensitivity is attained in this way. |
