Disc discriminator of optical disc player system

摘要

A disc discriminator of an optical disc player system is disclosed. The disc discriminator has a 4-split photo-detector for converting the beam concentrated by the optical pickup unit into an electric signal by means of a plurality of photo diodes divided into first through fourth quadrants. A push-pull signal generator is provided for amplifying a difference between signals generated from two pairs of photo diodes which are symmetrical in the upper and lower sides from the center of a track direction, and generating a push-pull signal. A comparator compares the push-pull signal generated from the push-pull signal generator with a predetermined reference voltage, and generates a digital video disc/compact disc discrimination signal discriminating between a digital video disc having the thickness of 0.6 mm and a compact disc having the thickness of 1.2 mm.