| 摘要 |
PURPOSE: To obtain a high contrast by forming a recording medium in such a manner that the reflection contrast of the light polarized perpendicularly to an incident surface is larger than 0.5 and the sum of the reflection capability to the light polarized parallel and perpendicular thereto is at least 8%. CONSTITUTION: A Te70 Ge30 layer of a memory layer and an SiO2 layer which is a transparent layer are formed on a glass substrate. The reflection contrast in the wavelength of incident light to the light polarized perpendicularly to the incident surface is larger than 0.5. Namely, the component polarized perpendicularly to the incident surface hardly reflects or does not reflect at all at either of two changeover states. Simultaneously, the component polarized parallel therewith still reflects powerfully and, therefore, only the parallel polarization component or the sum of the parallel and perpendicular polarization components is usable for maintaining ordinary focusing and tracking control servo functions. |
