Optical recording medium and recording and reproducing method using the same

A method of recording information in a phase-change optical recording medium capable of recording information at a linear speed in a range of 2.4 to 5.6 m/s, and erasing recorded information therefrom, said phase-change optical recording medium comprising a substrate, a first dielectric layer, a recording layer, a second dielectric layer, a light reflection and heat dissipation layer, and an overcoat layer, said first dielectric layer, said recording layer, said second dielectric layer, said light reflection and heat dissipation layer, and said overcoat layer being successively overlaid on said substrate, said recording layer (1) comprising a phase-change recording material which comprises as constituent elements Ag, In, Sb, Te, and N and/or O with the respective atomic % thereof being .alpha., .beta., .gamma., .delta. and .epsilon. (the total atomic % of N and/or O), which are in the relationship of:

• 0<.alpha..ltoreq.6,
• 3.ltoreq..beta..ltoreq.15,
• 50.ltoreq..gamma..ltoreq.65,
• 2.ltoreq..delta..ltoreq. 35.
• 0.ltoreq..epsilon..ltoreq.5, provided that .alpha.+.beta.+.gamma.+.delta.+.epsilon.=100, and (2) having a recrystallization upper-limit linear speed ifn a range of 2.5 to 5.0 m/s, under the conditions that a ratio of erasing power (P.sub.2e)/writing power (P.sub.2w) at a linear speed in a range of 2.4 to 2.8 is greater than a ratio of erasing power(P.sub.4e)/writing power (P.sub.4w) at a linear speed in a range of 4.8 to 5.6 m/s.

A method of reproducing information recorded in a phase-change optical recording medium capable of reproducing recorded information therefrom by controlling a reproduction light power of a reproduction light for reproducing recorded information in accordance with a reproduction linear speed, said phase-change optical recording medium comprising a substrate, a first dielectric layer, a recording layer, a second dielectric layer, a light reflection and heat dissipation layer, and an overcoat layer, said first dielectric layer, said recording layer, said second dielectric layer, said light reflection and heat dissipation layer, and said overcoat layer being successively overlaid on said substrate, said recording layer (1) comprising a phase-change recording material which comprises as constituent elements Ag, In, Sb, Te, and N and/or O with the respective atomic % thereof being .alpha., .beta., .gamma., .delta. and .epsilon. (the total atomic % of N and/or O), which are in the relationship of:

• 0<.alpha..ltoreq.6,
• 3.ltoreq..beta..ltoreq.15,
• 50.ltoreq..gamma..ltoreq.65,
• 20.ltoreq..delta..ltoreq.35,
• 0.ltoreq..epsilon..ltoreq.5, provided that .alpha.+.beta.+.gamma.+.delta.+.epsilon.=100, and (2) having a recrystallization upper-limit linear speed in a range of 2.5 to 5.0 m/s, under the conditions that a ratio of erasing power (P.sub.2e)/writing power (P.sub.2w) at a linear speed in a range of 2.4 to 2.8 is greater than a ratio of erasing power(P.sub.4e)/writing power (P.sub.4w) at a linear speed in a range of 4.8 to 5.6 m/s.