Initialization process for a phase change recording medium with a zero

Abstract

The present invention relates to a production process and a production apparatus for the optical information recording media comprising a material thin film which exhibits a reversible change of the optical characteristics by the irradiation of an energy beam such as a laser beam on the substrate. By dropping the emission strength instantly to the virtual zero level after having the emission for a specified time in conducting the initial crystallization process, both a large irradiation power and a short irradiation time can be achieved to reduce the various thermal damages. The charging time can be shortened. In the production of optical information recording materials with single side structure, in particular, by applying an annealing process in combination with a formation process of the resin protection layer or a recording thin fil initialization process, the warp or distortion of media caused by the contraction of the ultraviolet ray curing resin layer or the recording thin film layer can be reduced or corrected to realize an optical information recording medium having excellent servo characteristics. Further, by having at least one of two media to be affixed with a transmissivity of an ultraviolet ray of 3% or more as a method to comprise an optical information recording medium with double sides structure not liable to have a warp or distortion, an ultraviolet ray curing resin can be used as an adhesive, resulting in simplifing the production process.