Method of recording information in phase-change recording medium and recording medium for use in the method

A method of recording information in a phase-change recording comprising the steps of:

• conducting a test recording with the application of a laser beam to said phase-change recording medium, said laser beam comprising a comb-shaped pulse train, with a duty ratio of said comb-shaped pulse train being changed, thereby forming laser-beam applied portions in said recording medium,
• applying light to said laser-beam applied portions to measure the intensities of the light reflected from said laser-beam applied portions, and
• obtaining the relationship between said intensities of the light and the duty ratios corresponding thereto in order to specify a pulse strategy for recording information in said phase-change recording medium.

A method of recording information in a phase-change recording medium with a predetermined recording line speed, comprising the steps of:

• conducting a test recording with the application of a laser beam to a predetermined portion of said phase-change change recording medium, said laser beam comprising a comb-shaped pulse train which comprises a plurality of pairs of pulses, one with a pulse width T1 and a recording power P1, and the other with a pulse width T2 and a recording power P3, wherein P1 and P3 are in the relationship of P1>P3 in terms of the intensity of the light of said laser beam, with a duty ratio of said comb-shaped pulse train portion, defined by T1/(T1+T2) wherein 1/(T1+T2) is a clock frequency, being changed, thereby forming laser-beam applied portions in said recording medium,
• applying light to said laser-beam applied portions to measure the intensities of the light reflected from said laser-beam applied portions, and
• obtaining the relationship between said intensities of the light and the duty ratios corresponding thereto in order to specify a pulse strategy for recording information in said phase-change recording medium.