| 摘要 |
PROBLEM TO BE SOLVED: To obtain a recording area without teardrop-like area by controlling a laser beam by a PM-EFM signal, heating the recording area of a sufficient time phase change for phase change, and then intermittently emitting the beam. SOLUTION: The laser beam modulator comprises an EFM signal input unit 10 for receiving the 8-14 modulated signal, and a clock pulse generator 20 for generating a reference sampling clock pulse having a predetermined period of 4.32MHz. The EFM signal represents digital data to be written on a rewritable optical disk by using a laser beam, and has ON and OFF times of repetition of a series of high and low level signals. The beam is controlled by the length of the ON and OFF times of the signal. |
