| 摘要 |
<p>PURPOSE:To suppress the increase of a track error even when track bending, or the bending of a head locus at a reproduction side due to environment is generated, to lower requirement levels for parts accuracy and assembling accuracy, and to enable a cost down, by adding an offset voltage on a tracking error voltage, changing the offset voltage, and controlling the voltage so as to minimize an error rate. CONSTITUTION:A shift control is performed by adding an offset voltage VO on the output voltage VE of a circuit to detect the tracking error, and minimizing the error rate. A track bending detection circuit 23 which selects the value of the offset voltage VO, decides that the track bending is generated when the tracking error is small if a track center error rate is larger than a track mean error rate, and also, it approaches to a tracking error signal, and outputs an appropriate off-set voltage VO. By switching the offset voltage VO at various kinds of levels, and minimizing the error rate, the optimum locus relation of a track to a head can be obtained.</p> |
