| 摘要 |
PURPOSE:To protect recorded contents from destruction, by detecting the occurrence of a situation that the reaching position on a disk of an optical beam made incident on the disk is abruptly moved in the direction traversing tracks just before the situation occurs and immediately stopping the signal recording operation. CONSTITUTION:When, for example, extrenaly shock is given at the time of recording operation and the optical spot on a disk 1 of an optical beam made incident on the disk 1 from an optical head 2 is abruptly moved in the direction traversing tracks, a tracking error signal TE' is given from a signal forming circuit 4 and supplied to the positive input terminal of a level comparator 19 and negative input terminal of another level comparator 20 through a switch 12. Both outputs are supplied to a gate circuit 21 and a signal Sp which appears at the output terminal of the circuit 21 sets an R-S FF22 at the rising time t1. Therefore, the output signal So of the R-S FF22 becomes high level (h) and an operation mode control circuit 9 interrupts the recording operation. |
