| 摘要 |
PURPOSE:To obtain a light output pulse having no distortion by connecting a pulse elongating circuit with the base terminal of a transistor for driving a semiconductor laser of a pair of transistors for forming a differential circuit, and connecting a delay circuit of an inverted pulse signal with the base terminal of the other transistor to compensate the delay of the rise of the laser. CONSTITUTION:An NRZ code an inverted code inverted from the NRZ code are supplied to a comparator 9 to output a signal equal to the NRZ code and an inverted signal from the NRZ code to inverters 6, 10 to output a pulse signal delayed at time and inverted in polarity. Thereafter, the pulse signal and a signal equal to the NRZ code are supplied to an OR gate to supply a pulse signal delayed at time 2tau from the timing of fall of the NRZ code to the base terminal of a transistor 1. When the types of inverters 6, 7 are determined so that the predetermined time and the delay time 2tau become equal, the light emitting time of a semiconductor laser 3 becomes merely delayed by 2 tau. |
