Optical information recording medium, method of manufacturing the optical information recording medium, and method of and apparatus for recording/reproducing optical information

An optical information recording medium comprising:

• a transparent substrate having a concentric circular guide groove or a spiral guide groove, said guide groove having land portions and groove portions formed thereon;
• and
• a phase change type recording layer over said transparent substrate, said recording layer being crystallized by initializing with laser radiation;
• wherein information that indicates a standard recording linear velocity Vr and/or a maximum recording linear velocity Vh is stored on the medium, said stored information being recorded onto said substrate;
• wherein, while irradiating land portions or groove portions formed on said guide groove with energy to melt the material of said phase change type recording layer and while increasing a linear velocity of said medium and scanning said land portions or groove portions formed on said guide groove with said energy, the linear velocity at which the reflectivity of said optical information recording medium decreases, in comparison to that before said irradiating with said energy, is defined as uppermost recrystallization linear velocity V;
• wherein the uppermost recrystallization linear velocity V at a time when a focused semiconductor laser beam irradiates said groove portions or land portions of said guide groove satisfies a relation, the focused semiconductor beam being used for recording or reproducing,
• V≧Vr×0.85
• or
• V≧Vh×0.85;
• and
• wherein a track pitch of said guide groove is between 0.2 and 1.4 μm, and the uppermost recrystallization linear velocity V is between 16 and 24 m/s.