| 摘要 |
PROBLEM TO BE SOLVED: To obtain always appropriate recording state corresponding to the change of the state such as change in a recording layer, change in wavelength of a laser beam, or the like, when an optical disk is being recorded. SOLUTION: Asymmetry, which is a parameter for evaluating the quality of the recorded signal, is changed with the recording depth of a pit. Meanwhile, the recording depth of the pit is made to correspond to a ratio HL/HS of a peak value HS of the reflected light power at the initial time on the start of projection of the recording laser beam and subsequent stabilized value HL, and the ratio HL/HS is changed with the recording power. Then, the HS and the HL are detected at the recording time of the optical disk, and the value for instructing the recording power is outputted from a comparison means 26, so that the detected values coincide with the value set by a ratio setting means 24 on the basis of the trial writing, then the output power of a laser diode in an optical head 12 is controlled via an ALPC circuit 28. |
