| 摘要 |
Since the conventional optical disk recording/reproducing apparatus cannot correctly measure a power of a main beam that is a part of the laser light outputted from an objective lens and is focused on a recording layer to contribute to recording/reproducing, it is difficult to accurately control a read power. A ratio of a proper read power to a threshold power of erasing is acquired beforehand. The read power is determined by measuring the threshold power of erasing and multiplying it by the ratio when learning of the read power is performed for each drive device. According to the read power learning method of this invention, it becomes possible to determine the proper read power regardless of performance variance of an optical pickup and sensitivity dispersion of a medium. |
