Optical recording medium and optical recording method using the same

摘要

An optical recording medium having a layer of recording material provided on a substrate, the material having an optical property which is changed reversibly by means of light or heat, so that writing/reproducing or writing/reproducing/erasing of information is performed by using the reversible change of the optical property of the recording material layer. The recording material is composed of a plurality of elements and is capable of taking, as a melt state thereof, a selected one of a single phase state and a two-phase coexistent state. An optical recording method for performing writing/reproducing/erasing of information uses a reversible change of an optical property of the recording material layer by irradiating the recording material layer with a high-power light beam so as to melt it into a single phase state and then cooling the recording material layer so as to form a phase-changed portion corresponding to a recording state or an erasing state. The recording material layer is irradiated with a low-power light beam so as to be melted into a two-phase coexistence state and then cooled so as to form a phase-changed portion corresponding to an erasing state or a recording state.