OPTICAL DISK DEVICE AND OPTICAL DISK

摘要

PURPOSE:To record information under an excellent S/N state and to improve recording accuracy by detecting infrared rays radiated from an optical disk with the aid of an infrared rays detector and controlling the recording power of a laser beam based on the detected output. CONSTITUTION:The infrared rays 11 radiated from the magneto-optical disk 1 is detected by the infrared rays detector 13a and the detection signal thereof is inputted in a signal processing circuit 14. The CPU 14b of the circuit 14 stores the correlation of the temperature and the S/N value of the disk 1, calculates the optimum recording power of the laser beam 3 based on the output of the detector 13a and outputs a command to a laser modulator 8. The modulator 8 controls a current supplied to a laser head 4 based on the command. Thus, the temperature of the disk is accurately detected at a high speed and an information signal 6 is recorded under an optimum state.