Tracking servo signal generating device in an apparatus for reading recorded information

摘要

A tracking servo signal generating device in a tracking servo control system in a recorded information reading apparatus adapted to deviate an information detecting point in the direction perpendicular to a target recording track on a recording medium in accordance with the tracking servo signal so that the information detecting point accurately traces the recording track, which comprises detecting means for producing a pair of detection signals a difference between which represents amount and/or direction of deviations of the information detecting point from the recording track in the direction perpendicular to the track. The pair of detection signals is processed to produce a first difference between low frequency components of the detection signals and a second difference between envelope components of high frequency components of the detection signals. The first and second differences are mixed to produce the required tracking servo signal, thereby to suppress erroneous components in the resulted tracking servo signal caused by optical and/or mechanical distortions in the recorded information reading apparatus and/or in the recording medium per se.