Phase-change optical recording method using pulse width modulation technique

摘要

When recording data according to the PWM recording system by modulating signals, pulse modulation for pulse modulation for recording for recording a 0 signal or the like having a signal width of nT (T: Clock time) after modulation is a continuous electro-magnetic wave at a power level e, a record signal pulse array for recording a 1 signal or the like having a signal width of nT after modulation comprises a pulse section fp having a time width x and a power level a, a multi-pulse section mp in which a low level pulse at a power level b and a high power pulse at a power level c having a time width T in total alternately appear (n-n') times in all with a duty ratio y, and a pulse section op having a time width z and a power level d, and x, y, z are integers satisfying the conditions of 0.5 T≦x≦2 T, 0.4. ltoreq.y. ltoreq.0.6 and 0.5 T≦z≦1 T, and n' is a positive integer which is equal to or smaller than n, and controls are provided so that the condition of (a and c) e (b and d) is satisfied.