OPTICAL MODULATION SYSTEM

摘要

PURPOSE:To simplify the circuit constitution and to enhance the excellent frequency characteristic by changing a bias current flowing to an LED. CONSTITUTION:A buffer circuit 1 feeds an electric input signal to an LED driver 2 and a bias control circuit 3, the LED driver 2 outputs a modulation signal superimposed with a prescribed DC signal, a capacitor 4 cuts off the DC component and the bias control circuit 3 inputs a signal from the buffer circuit 1 to detect the signal level. Then the bias signal corresponding to the signal level and the LED 5 outputs an optical signal.