METHOD FOR RECORDING, REPRODUCING AND ERASING INFORMATION

摘要

PURPOSE:To attain recording, reproducing and erasing by one energy beam spot changing its level by using a recording medium provided with a reversible phase changing type information recording film to be rapidly changed at its speed in accordance with radiation energy. CONSTITUTION:The reversible phase changing type information recording film 2 laminated on a disk 1 together with a protection film 3, changing its phase rapidly in accordance with radiation energy and optionally changing its physical constant in accordance with the rapid change of the phase is irradiated by a laser beam radiated from a semiconductor laser 10. Since the film 2 is used, data can be recorded, reproduced and erased to/from the disk 1 by an energy beam spot such as a laser beam by changing an laser power level.