| 摘要 |
PROBLEM TO BE SOLVED: To precisely determine the optimum recording power value by OPC (optimum power control) by preventing incomplete erasure in PCA(power calibration area) SOLUTION: The PCA of an optical disk 4 is erased at multiple levels of erase power value by a controller 15; the peak and bottom values are detected of the reproducing signal from the PCA after the erasure; an amplitude is determined on the basis of these peak and bottom values; the erase power value at the time when the determined amplitude becomes smaller than a prescribed value is decided as the optimum erase power value for DC-erasing the PCA; and the PCA of the optical disk 4 is DC-erased at that optimum erase power value. |
