| 摘要 |
PROBLEM TO BE SOLVED: To improve the uniformity of a power margin characteristic without shortening the life of a semiconductor laser. SOLUTION: This control circuit has a laser diode 1, a voltage-current conversion circuit 19, a photodiode 2 which detects light emission output, an error amplifier 12 for recording which compares the output of this photodiode 2 and a recording power set voltage 21, and a hold circuit 14 which holds the output of this error amplifier 12 for recording and controls the output current of the voltage-current conversion circuit 19 in accordance with the output from this hold circuit 14. The hold circuit 14 adds the driving voltage by ΔV to the value held in the ALPC(auto laser power control) section of a continuous servo tracking system of the ISO standards of an optical disk holding the driving voltage in a hold voltage correcting and adding circuit 27 and sets the peak power value of the pulse light emission at the time of data recording higher than the recording power set value by DC lighting in the ALPC section. |
