OPTICAL RECORDING SYSTEM AND OPTICAL RECORDING MEDIUM

摘要

PURPOSE:To allow reloading of data with the inexpensive optical recording medium by irradiating an expansion layer consisting of a resin having elasticity with a laser beam and deforming a layer consisting of a memory resin having a proximate shape. CONSTITUTION:The laser beam emitted from a laser oscillating section 5 is hardly absorbed in the recording layer 4 and intrudes through the recording layer 4 into the thermal expansion layer 3 and is absorbed by the thermal expansion layer 3. The recording layer 4 is then built-up by the thermal expansion of the thermal expansion layer 3 and a pit is formed. A gap 6 is formed between the thermal expansion layer 3 and the recording layer 4 at this time. Shape recovery takes place in the recording layer 4 if the pit part of the recording layer 4 is irradiated with the laser beam from the laser oscillating section 7 at the time of erasing the data. The pit is flattened by this shape recovery and the data is erased.