| 摘要 |
PURPOSE:To effectively short the emission and stop of a light from a semiconductor laser by forming overshoot and undershoot at the drive current of the semiconductor laser diode. CONSTITUTION:A transistor TR3 employs an auxiliary amplifying transistor, and DIF is differentiating circuit. Figure A shows an input signal waveform of the transistor TR1, Figure B shows the waveform of the collector at the left side transistor of the TR2 when a circuit with only a transistor TR2 is operated, Figure C shows the waveform passed through the transistor TR3 and the differentiating circuit DIF, and Figure D shows the waveform for driving a laser diode LD as the total waveform of the waveforms in Figures B and C. Since the laser diode operates to abruptly rise and fall the input signal waveform through this circuit, a light output waveform similar to rectangular shape can be obtained, an accuracy in an output signal corresponding to the input high speed signal can be improved. |
