| 摘要 |
PURPOSE:To certainly erase recording by the change of the crystal state or phase of a recording layer by forming recording to a recording medium, wherein a photothermal converting layer absorbing recording light to convert the same to heat and a recording layer substantially transparent to recording light and reversibly generating the change of a crystal state or phase by heat to perform recording and erasure are provided on a substrate, by the short-time irradiation with light and erasing the same by the irradiation with light applied for a time longer than that at the time of recording. CONSTITUTION:A photothermal converting layer 2 absorbing recording light to convert the same to heat is provided on a substrate 1 and a recording layer 3 substantially transparent to recording light and generating the reversible change of a crystal state or phase by heat and a protective layer 4 are provided thereon. Next, semiconductor laser beam is condensed to the recording medium thus formed in a diameter of 5mum so that the intensity on the recording medium becomes 2mW and scanning is linearly applied so as to be superposed on a recording part. The linear speed at this time is set to 50mm/sec and the irradiation time of one point of the recording medium is set to 100musec. After irradiation, when the recording medium is observed by a polarization microscope in the same way as that before irradiation, recording is erased in the scanning part due to erasing beam in a strip shape with width of about 3mum. |
