| 摘要 |
PURPOSE:To rapidly perform laser diode rising by providing a transistor which outputs the control signal for LD drive circuit to drive the laser diode and grounding the emitter side of the transistor via a peak-value detecting circuit. CONSTITUTION:The titled controller is provided with a transistor 8 that outputs the control signal for an LD drive circuit 3 to drive a laser diode 1 and the emitter side of the transistor 8 is grounded via a peak-value detecting circuit 20. Since the voltage for controlling the circuit 3 has been impressed in the circuit 20, a time constant necessary for the conventinal mean value detecting circuit is unnecessary to be taken into account. Therefore the duration in which an optical amplitude will reach a constant level can be shortened. While, the emitter output voltage of the circuit 8 controls the circuit 3 according to the held values at every burst signal SB rise, and the output voltage of the circuit 3 controls the operation of the LD1. Thus an optical burst output signal with constant amplitude can be obtained. |
