| 摘要 |
PURPOSE:To stabilize the jump operation of recording and reproducing light to shorten jump time by extending the pulse width of a decelerating pulse signal and reducing the speed for a certain period after the recording and reproducing light reaches an adjacent track to turn on the track servo. CONSTITUTION:A pulse signal D outputted from a terminal QA of a counter 5 is inputted to one input of an OR circuit 10, and the pulse signal has the rise and the fall of waveform distorted by a resistance R and a capacitor C. Two pulse signals are inputted to the OR circuit 10 at the same timing, and the fall of the pulse signal D is delayed by DELTAT to obtain a pulse signal D2. Pulse signals C and D2 are inputted to a differential amplifier 6, and a pulse signal J which has a pulse width obtained by adding the time DELTAT to the pulse width of the normal decelerating pulse signal is outputted. As the result, the decelerating pulse signal is added for the time DELTAT after the reproducing light reaches the adjacent track to turn on the servo, and the light tries to return to the adjacent track with a stronger force to reduce the overshoot, and the jump operation is stabilized, and a jump time is shortened. |
