| 摘要 |
PURPOSE:To attain multiple recording at one and same location by using a recording film including certain kinds of substances with different melting points or transposition temperature. CONSTITUTION:The recording film formed by the combination of some kinds of crystals with different melting point of transposition temperature is used for the recording medium and in selecting properly the power at recording, number of recording information is increased by the number of kinds of crystals at maximum. This is because the molten crystal differs from the magnitude of power at the recording. The number of stepwise reflectances is obtained by the number of kinds of crystals such as reflectance '0' at the complete crystal state, final reflectance '1' when the crystal with the lowest melting point is molten and the reflectance is decreased, and the final reflectance '2' when the crystal with the 2nd lowest melting pint is molten and the reflectance is lowered, and so on. Since the change in the reflectance is caused at one and same location, multiple recording is attained. Even when films whose crystal differs from the melting point are laminated, multiple recording is attained similarly. |
