Tracking error signal detecting method selectively using a push-pull method, an improved push-pull method, and a three beam method and optical recording/reproducing apparatus using the same

Abstract

An optical recording/reproducing apparatus includes an optical pickup and a signal processor. The optical pickup includes an optical splitting device which splits light emitted from a first light source into a main light beam and sub-light beams which are symmetrical with respect to the main light beam and irradiates the split light beams on a recording medium, and a light detection device which receives the main light beam and the sub-light beams reflected by the recording medium, so as to detect a tracking error signal in a three-beam method and one of a push-pull method and an improved push-pull method. The signal processor receives the detection signals output by the light detection device and detects the tracking error signal in the three-beam method and one of the push-pull method and the improved push-pull method, and otherwise selectively detects the tracking error signal in one of the three-beam method, the push-pull method and the improved push-pull method, so as to realize an optimal tracking servo-control. Since a selective use of one of the improved push-pull method, the push-pull method and the three-beam method can be made according to the type of an optical disc, the optimal tracking servo-control can be realized regardless of the depth of a pit in an optical disc during a reproduction of data from the optical disc, such as a non-rewritable optical disc.