| 摘要 |
PURPOSE:To detect the middle point between tracks and to make jump operation of an optical spot stable, by detecting the peak point of a total reflected luminous amount from a disc and switching the polarity of a control signal driving the optical spot at the peak point. CONSTITUTION:In a digital optical disc, the jump operation shifting the optical spot from a guide groove to a guide groove in a short time where recorded parts and nonrecording part are mixed, is made stable, and the average value of the reflected luminous amount from the recorded track is a half the nonrecording track, and although a track shift detecting signal E1 is largely changed, the peak position of a total reflected luminous amount E2 is unchanged. Thus, to detect the middle point between the tracks, this peak point is detected and denoted as a switching timing point for acceleration and deceleration, and to improve the stability of jump, the optical spot is once positioned at the middle point of the tracks and led to the objective track. |
