Phase change type optical recording medium and recording method therefor

摘要

A recording method forms recording marks according to a mark length modulation by irradiating a pulse-shaped light beam with respect to a crystallized phase change recording layer of a phase change type optical recording medium which comprises at least the phase change recording layer and a reflection layer on a substrate. The recording method irradiates a light beam formed by a single recording pulse when forming a recording mark having a size less than or equal to a predetermined size N, where the predetermined size N is set with reference to a reference size which is sum of a beam spot diameter of the light beam and a distance traveled by the light beam within a time amounting to a sum of rising and falling time constants of a light beam power, and irradiates a light beam formed by a plurality of recording pulses when forming a recording mark having a size greater than the predetermined size N.