| 摘要 |
PURPOSE:To eliminate an unstable tracking state generated by a shock vibration of a disturbance or a jump of an optical pickup, etc. by inserting a limiting circuit into an inlet side of a servo-circuit, and forming its envelope to an up-and- down symmetrical shape by a limiting action even when an unsymmetrical signal seen in a traverse signal, etc. in case when the optical pickup has moved has been inputted, so that its signal is inputted to an integration circuit. CONSTITUTION:A signal controlling circuit 10 is formed by diodes D1, D2 connected in reverse to each other, and a unit amplifier G, only a signal of a constant level of positive and negative is inputted to an integration circuit 5, and it does not occur that an unstable AC signal component is generated in a feeding servo-signal. However, a tracking error signal in a normal reproducing state is supplied to the integration circuit 5 without being short-circuited by said diodes D1, D2, and supplied to a sled feeding motor 7 as a feeding servo-signal for moving an optical pickup device 2 in the radial direction. |
