| 摘要 |
PURPOSE:To prevent completely mis-recording and double recording caused by an unexpected track jump, by detecting a track jump from a guide track recording information to other guide track out of a track crossing signal, and changing the optical power of a laser light source from the recording state into the non-recording state. CONSTITUTION:When jumping operation is executed, a crossing signal 51 is detected in a tracking error signal similarly the same as a track jump, because an optical spot crosses between pits from a pit of the guide track in the jumping. The cross signal 51 should not be discriminated as track jump. A jumping section pulse 52 and an output of positive/negative comparators 32, 33 are ANDed at an AND gate 56 so as not to discriminate jumping pulses 53, 54 of the jumping section formed with the crossing signal 51 as a track jump signal. The track jump only is detected accurately by using the first leading edge of the pulse of a track jump detecting signal 56 obtained in this way, allowing to reduce the optical power from the recording state into the reproducing state. |
