| 摘要 |
PROBLEM TO BE SOLVED: To optimally set the recording power of a laser beam without necessitating a trial writing at the time of operation, by calculating the optimum recording power of the laser beam and storing the data in a nonvolatile memory as the setting value data of a recording power. SOLUTION: The detection output SDP of the power of an output laser is supplied from an optical head 14 and also a power control signal SPC is supplied from a system controller 16 to a laser driving circuit 15. The power of the laser beam to be outputted from the laser diode of the head 14 is controlled so that powers at a recording and a reproduction become respectively optimum. Recording data RD are supplied to the circuit 15 at the time of a recording and the laser power is driven by the circuit 15 so that the laser power changes according to the data RD. Thus, the data RD are recorded on the data part of a magnetooptical disk 11. At the time of reproduction, reproduced signals SMO, SRF from the disk 11 are obtained from the head 14 and, moreover, a tracking error signal ET and a focus error signal EF are outputted from the head 14. |
