Magnetooptic disc apparatus and recording medium

An optical information recording and reproducing method comprising the steps of:

• converting an information signal to be recorded into a code train;
• modulating a light beam into a light pulse train in accordance with said code train;
• irradiating the light pulse train onto a recording medium;
• recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train;
• photoelectrically converting the light from the recording medium to thereby obtain an electric signal waveform;
• processing said electric signal waveform;
• converting a signal obtained by processing said electric signal waveform into a pulse signal;
• detecting the code train recorded on the recording medium from the pulse signal;
• decoding the detected code train to the information signal;
• modulating the light beam by a special test signal;
• forming a test pattern on the recording medium;
• reproducing the test pattern;
• and
• evaluating output waveforms of the reproduced test pattern;
• wherein a unit of the light pulse train for forming one of said recording marks has pulses of power levels equal to or larger than a first level P.sub.w, wherein a light pulse train which does not form said recording marks has pulses of power level equal to or smaller than a second value P.sub.as, wherein said light pulse train for forming said recording marks has a region of a power level which is equal to or smaller than a third value P.sub.r that is at least one of before and after said light pulse train for forming said recording marks, wherein P.sub.w >P.sub.as >P.sub.r, and wherein the power level P.sub.as is controlled on the basis of results obtained in the evaluation, independently of the power levels P.sub.w and P.sub.r.

An optical information recording and reproducing method, comprising the steps of:

• converting an information signal to be recorded into a code train;
• modulating a light beam into a light pulse train in accordance with said code train;
• irradiating the light pulse train onto a recording medium;
• and
• recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train, wherein said light pulse train includes recording pulses corresponding to said recording marks and auxiliary pulses which do not correspond to said recording marks, wherein power levels of said recording pulses are set higher than power levels of said auxiliary pulses, and wherein shapes of said recording marks are controlled by controlling the power levels of said auxiliary pulses which are applied just before application of said recording pulses.

An optical information recording and reproducing method, comprising the steps of:

• converting an information signal to be recorded into a code train;
• modulating a light beam into a light pulse train in accordance with said code train;
• irradiating the light pulse train onto a recording medium;
• recording the code train as recording marks by at least one of a heat function and heat interference of the light pulse train, wherein said light pulse train includes recording pulses corresponding to said recording marks and auxiliary pulses which are irradiated before said recording pulses and used for preheating said recording medium, and wherein power levels of said auxiliary pulses are controlled;
• and
• wherein said step of recording the code train as recording marks comprises a step of providing a period having a power level lower than the power levels of said auxiliary pulses.