| 摘要 |
PURPOSE:To improve an erasing ratio by providing multiple interference films having prescribed characteristics adjacently to a recording film which is a phase change film and setting the reflectivity of the recording film so as to have the extreme value during the course of crystallization. CONSTITUTION:The recording film 7 which is changed in phase by irradiation of laser power and is thereby changed in the degree of crystallization and the reflectivity and the interference films 6', 6'' which are adjacent to the film 7 and make multiple interference of the dielectric material having a high refractive index, etc., are laminated on a substrate 5, by which the phase change optical information recording carrier is formed. The reflectivity during the course of the crystallization based on the irradiation of the laser power of the film 7 has the extreme value from the simple change if the refractive index and film thickness of the films 6', 6'' are set to prescribed values in accordance with the optical constant of the film 7. The recording near the irradiated point is uniformly erased if the laser power corresponding to the value near this extreme value is used as the laser power. The erasing ratio is thus increased. |
