| 摘要 |
<p>An optical disc system includes a gain offset unit for giving a gain and an offset to an input reproduction signal, an A/D converter, a peak detector, a bottom detector, an amplitude detector for calculating a signal, an offset detector for calculating a signal offset, a drop out detector for detecting a defect of an input signal, and a control unit for performing gain control and offset control of the gain offset unit and capable of holding control operation or switching control speed by an external hold signal input. The optical disc system detects a defect of a recording medium and holds gain control and offset control or changes the control response speed so as to maintain the signal amplitude and offset in the A/D converter input always constant.</p> |
