Optical recording and reproducing apparatus having a pickup head including a main prism with reflecting surfaces for splitting the reflected beam

摘要

An optical recording and reproducing apparatus for optically recording and reproducing information on and from a disk includes a light source for generating a parallel beam. A movable optical system condenses the parallel beam from the light source on the disk, splits the beam into two different beams, and moves in the radial direction of the disk. A split-beam detecting device has two light receiving surfaces which receive part of the two different beams obtained in the movable optical system. A and a control device effects tracking control by moving the movable optical system in the radial direction of the disk in accordance with respective detection signals output from the two light receiving surfaces.