| 摘要 |
PURPOSE:To permit repetitive recording and erasing by irradiating layer light on a member for optical recording formed by alternately laminating plural times dielectric layers and Se or its alloy layers on a substrate. CONSTITUTION:The dielectric layers 2, 4, 6, consisting of SiO2, Al2O3, etc. and Se layers or alloy layers 3, 5 contg. Se are provided on the substrate 1 consisting of a polymethyl methacrylate, etc. The Se or Se alloy layers are made thin in order to increase the crystallization temp. and to extend the life at a room temp. and are made into >=2 layers of medium constitution in order to obtain substantial contrast by the crystal-amorphous transition. The Se, etc. are in the amorphous state right after the prepn. of the films. Laser pulses of a relatively long pulse width are irradiated thereon to gradually heat said layers to the crystallization temp. or above and to crystallize the layers by the annealing effect, by which recording is executed. The laser pulses of a shorter pulse width and larger power are then irradiated on said films to heat the layers to the m.p. or above and thereafter the layers are quickly cooled to quench the same in the disordered state of atoms. by which the crystal layers are made amorphous and erasing is thus executed. |
