SEMICONDUCTOR LASER DRIVING CIRCUIT

摘要

PURPOSE:To obtain a semiconductor laser driving circuit at low power consumption and yet having excellent response characteristics by a method wherein the DC bias current is controlled to be proportional to the increase and decrease in the modulation current of a modulation circuit. CONSTITUTION:The value of DC bias current 1a is controlled to be proportional to the increase and decrease in the modulation current 1b. Through these procedures, the balance between the driving capacity of a modulation circuit 22 and that of an operation amplifier circuit 21 can be set up in a state of optimum thereby enabling a semiconductor laser diode LD to excite the output beams hv showing the fidelity toward electric signal Sin. Accordingly, the power consumption can be cut down to easily realize a compact unit by adopting a device using IC thereby enabling this simple semiconductor laser driving device displaying excellent performances to be obtained.