PURPOSE: To enable track control with high accuracy by calculating the average value of respective sample data for a driving signal in the case of control only by a feedback signal and executing reading of data and conversion to an analog signal synchronously with the rotation of an optical disk.
CONSTITUTION: A feed forward signal generator 7 is provided and the driving signal of an optical head 1 in the case of control only by the feedback signal is sampled only for one time rotation of the optical disk 1 with a prescribed cycle. Then, analog / digital conversion is executed and for each sample data, the average value is calculated and stored based on an L(=1,2,...) number of the sample data before and behind the objective sample data. Each average value is read out synchronously with the rotation of an optical disk 2 and digital / analog conversion is executed. Then, the average value is outputted as a feed forward signal. Thus, since the phase delay of the feed forward signal is eliminated, track error caused by the track eccentricity of the optical disk is improved and the track control can be executed with high accuracy.
TAMARU NAOYUKI
SATO TOSHITAKE
| JPS6126942A | 1986-02-06 | |||
| JPS5647932A | 1981-04-30 |