| 摘要 |
PURPOSE:To prevent erroneous erasing or erroneous recording by forming an irreversible recording region to the specific region of a recording layer consisting of a material which is reversibly changed in light transmittance or reflectivity. CONSTITUTION:An optical recording medium 3 is constituted by forming the recording layer 2 contg. the high-polymer material which is reversibly changed in a light scattering state and can maintain the state thereof and a light absorptive dye is formed on a substrate 1. For example, a phase sepn. polymer, high-polymer liquid crystal, etc., are used as said high-polymer material. The intensity of light scattering is decreased by projecting pulse light from a laser 4 for recording on the recording medium 3 to heat the recording layer 3, then rapidly cooling the same, by which the recording is executed. The output of the laser 4 is lowered and the laser is projected on the optical recording medium, then the difference in the quantity of the transmitted light is detected, by which the reproducing is executed. Erasing is executed by increasing the spot of the laser light from the laser 4, projecting this laser on the recording medium 2 to heat said layer, then slowly cooling the layer. Further, bits are formed on the recording layer 2 by increasing the output of the laser light. The light transmittance in this recording is not changed by the irradiation of the laser light. |
