TRACKING ERROR DETECTING METHOD AND OPTICAL INFORMATION REPRODUCING APPARATUS USING THE SAME

摘要

A tracking error detecting method and an optical information reproducing apparatus using the same are provided to perform tracking error detection sensitive to the reproducing beam efficiency and thus to reduce bit error rate. An optical information reproducing apparatus comprises an optical system(110), a surrounding beam splitter(150), a beam information detector(160), first and second beam detectors(172,174), and a signal processing part(180). The optical system projects the reference beam over the current track and first and second surrounding tracks. The surrounding beam splitter divides reproducing beam formed by the reference beam into main reproducing beam and first and second surrounding beams. The beam information detector detects the beam information from the main reproducing beam. The signal processing part outputs a tracking error by dividing the sum of the first and second surrounding beam strength errors by the sum of first and second surrounding beam strengths.