PURPOSE: To improve transition characteristics and following-up precision by driving a galvanomirror and a voice coil motor on the basis of detected results of a tracking error of a spot on an optical disc to a track, the angle of the mirror, and the position of the motor.

CONSTITUTION: A disc 1 is rotated around a revolving shaft 2 in a certain direction, and an optical head 3 is placed on a moving base 4, and the moving base is moved on a base 5 in accordance with rotation of a roller 6. The moving base 4 is connected to the voice coil motor consisting of a voice coil 8 and a magnet 9 through a supporting mechanism, and the current of the coil 8 is detected by a resistance 14 and an A/D converter 15 and is supplied to an arithmetic unit 25. A galvanomirror 17 and a galvanomirror displacement detector 18 which polarize the light spot are provided in the head 3, and the signal of the detector 18 is supplied to the unit 25 through a differentiator 20 and an integrator 22. The tracking error of the light spot to the track is given to the unit 25 by a photodetector 19. The transition characteristic and the following-up precision are improved by the unit 25.