| 摘要 |
PURPOSE:To prevent the destruction of data and to assure the data by stopping recording information at the time of outputting a track deviation signal being in excess of an allowable deviation amt. or occasionally recording the information in another place and resuming the recording if no track deviation takes place when the information is reproduced again. CONSTITUTION:Information of a reproducing optical system 6 is inputted to a detecting means 13 to send out the track deviation signal. This signal 11 is inputted to a window comparator 14, and when the signal is deviated from a specified level range, the signal is made to be '0', and tracking is carried on with a signal 15 under the state of '1'. This signal may be a control signal for showing a closing and opening command of a tracking servo system. An output '1' of inverting '0' is passed through a gate 16 to be outputted as the track deviation signal 9. This signal is inputted to an FF 41 to be set to its rise, and is used as a gate control signal 17 for a recording signal. By this constitution, a track deviation is detected to stop recording, and this state information can be given to a control device. When the track deviation signal generated due to dust and a flaw is detected by the window comparator 14, its pulse width is narrow, so that, if this is below a prescribed time width, the signal is prevented from being inputted to the gate 16. |
