| 摘要 |
<p>PURPOSE:To enable a stable fine slow reproduction even in a tracking system using a pilot signal by performing a tracking control using the four types of pilot signals and varying the acceleration in accordance with a voltage value of a tracking error signal obtained in a stop interval during the fine slow reproduction. CONSTITUTION:A sample holding circuit (S & H) 2 samples the tracking error signal (b) by a sample pulse (c) and outputs a hold voltage (d). The pulse (c) is generated in a center position of a change point of an H-S signal (a). In the case of a still scanning, the voltage (d) goes to a Vo potential. In the case of a scanning deviated from the till scanning, the voltage (d) changes according to the quantity of the deviation from the Vo potential. The voltage (d) is inputted to a delay circuit 6 and is used as a signal varying the quantity of a delay according to the voltage value. From a terminal 5, an acceleration position command signal (e) is inputted and impressed to the delay circuit 6 and an output signal of the circuit 6 becomes to an acceleration setting pulse (f). Accordingly, a delay time of the circuit 6 is suitably set corresponding to the direction of the deviation and the automatically stable fine sow reproduction can be performed.</p> |
