| 摘要 |
PURPOSE: To enable the recording, erasing and reproducing of optical information by light of a single wavelength above 760nm and the reproducing by a CD player. CONSTITUTION: Plural light interference films 2a to 2d which are transparent to light of wavelengths of 780nm and 830nm and vary in refractive indices are laminated on a substrate 1 and a lower protective film 3, a recording film 4, an upper recording film 5 and a reflection film 6 are successively laminated and formed on the light interference film 2d. Both parts corresponding to the crystalline parts and amorphous parts of the recording film 4 described above are low in reflectivity and both these parts have a difference in reflectivity at the time of the 830nm and, therefore, the execution of the reproduction of the optical information in addition to the recording and erasing thereof. Further, either one part of both parts is high in reflectivity and the other part is low in reflectivity, therefore, the execution of the reproduction by the CD player is possible as well. |
