Centering detection system for an apparatus for playing optically readable record carriers

摘要

An apparatus as described for reading a record carrier on which information, for example video and/or audio information is stored in an optically readible track-shaped information structure. A deviation between the center of a read spot which is projected on the information structure and the center line of a track to be read can be detected with the aid of at least two detectors which are disposed in the far field of the information structure in different quadrants. With the aid of the same detectors a reference signal is obtained which is used for deriving a control signal for correcting the position of the read spot relative to the track to be read.