| 摘要 |
PURPOSE:To execute the stable tracking control without reducing the capability of track seeking by using track mark on a recording medium to perform tracing in the phase difference method and counting continuous grooves to seek a track. CONSTITUTION:The recording medium having both of concentric circle-shaped or spiral continuous groove and pit-shaped track mark is used, and two detection signals obtained from a light quantity detector 3 are subjected to waveform shaping by circuits 4a and 4b to obtain two digital detection signals C and d, and phases are compared with each other by a phase comparing means 5 to obtain a tracking error signal E from a phase difference pulse corresponding to the phase difference, and the tracking control is executed. A detection signal H obtained from a signal quantity detector 6 and difference means 7 is subjected to waveform shaping to obtain one pulse for one continuous groove which a head transverses, and the direction in which the head transverses the track is detected by a direction detecting means 13, and a track is seeked in accordance with the information. |
