| 摘要 |
PURPOSE:To obtain a high-precision and high-speed access function by providing a control means which turns on a tracking servo means in response to a rotation position signal in case that the tracking servo means is turned on after movement of a light spot. CONSTITUTION:In the stop mode, an optical pickup 8 is placed in such position that the light spot scans the position a length L1 distant form the center of a spindle 5; and when a position selecting signal Ss which starts reproducing from the position a length L2 (L1>L2) distant is given with a keyboard 26 in this state, a CPU turns on a switch SW2 to connect an integrator 21 to a power source +V. Thus, servo is so applied to a linear motor 17 that a pickup position signal Sp is changed while following up the variance of the output of the integrator 21, and the optical pickup 8 is moved to the innermost peripheral part from the position the length L1 distant from the center of the spindle in a high speed. The CPU stops moving the optical pickup 8 when signals Ss and Sp coincide with each other, and a one-pulse rotation position signal Sr is given from a pulse generator 7, and a switch SW1 is turned on to turn on the tracking servo. |
