Pickup device for a magneto-optical information recording system

摘要

An optical information reproducing device includes a light source for generating a light beam, an optical system for converging the light beam generated by the light source on a magneto-optical recording medium on which recording information is recorded and for converging a return light beam reflected from the magneto-optical recording medium, beam splitting means for splitting the return light beam into split light beams, first detecting means for receiving one of the split light beams to detect the intensity of the one of the split light beams, servo signal generating means for generating a tracking error signal and a focusing error signal based on the output of the first detecting means, an optical waveguide disposed between the beam splitting means and the first detecting means, the optical waveguide crossing an optical axis of the one of the split light beams, an optical coupler disposed on the optical waveguide for separating part of the one of the split light beams from the one of the split beams to form a guided light beam which is guided in the optical waveguide, second detecting means for receiving the guided light beam from the optical waveguide to detect the intensity of at least one polarization component of the guided light beam, and information signal reproducing means for reproducing the recording information based on the output of the second detecting means.