PURPOSE:To realize the stable jumping operation by changing relatively the energy fed at acceleration/deceleration in the operation in a tracking element independently at the jump up-down. CONSTITUTION:A direction signal 16 jumping down a light beam toward the outer circumferential direction of a tracking track of jumping it up toward the inner circumference, and a jumping start signal 17 are inputted to a command circuit 24. Command signals 28, 29, 30 are supplied to pulse generating circuits 25, 26, 27 from the circuit 24, inputted to the tracking element 15 via an adder circuit 13 and a drive circuit 14 and a converging lens 5 is accelerated for a prescribed time toward the outer or inner circumference. Then tracking error signal being an output of a differential amplifier 9 is sent to the circuit 24 via a zero cross detection circuit 21 and the circuit 24 decelerates the element 15 for a prescribed time at a prescribed rate. Thus, the stable jumping is applied.
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