PURPOSE: To decrease the noise at the time of rotating a disk by rotating reversely a disk at an approximately standard 1/N speed and jumping two light spots to 3 track outer circumference simultaneously for each prescribed number of rotation.

CONSTITUTION: Light spots A and B start from a second track position A0 and a first track position B0. After the reproduction is usually performed up to positions A1 and B1 of 1.05 rotation in a counterclockwise direction, 3 track jumping is performed in the outer circumferential direction and the spots arrive at a position A2 (2.97 track from A1) and a position B2 (2.97 track from B1). The reproduction information is written into a memory. Further, 3 track jumping is performed in the outer circumferential direction from counter-clockwise direction 1.05 rotated positions A3 and B3, the information is reproduced up to positions A4 and B4 (respectively 2.97 track from A3 and B3) and written into the memory. Thus, the light spots A and B are always rotated in the counter-clockwise direction, and 3 track jumping is performed in the outer circumference for each 1.05 rotation, the information written in the disk is reproduced. The reproducing switching time from the A surface to the B surface can be shortened, and the noise generation can be suppressed without the constitution complicatedness of a device.