Patent ID: 6466594
Filing Date: 2002-10-15
Classification: G06K,H01S

Abstract:
A laser modulating device for driving a laser diode to emit a modulated laser beam in accordance with input data, comprising:a monitoring system that detects output power of the laser diode and outputs a detection signal corresponding to the output power; a minimum output level setting system that outputs a minimum level signal defining a minimum output power of said laser diode; a modulating signal generating system that generates a modulating signal representing modulation information of the output power of said laser diode corresponding to input data; a first adder that outputs a sum of the minimum level signal and the modulating signal as a reference signal; a comparing system that compares the reference signal and the detection signal and outputs the driving signal so as to make the detection signal coincide with the reference signal; and a circuit that supplies the modulating signal to said laser diode, the modulating signal being added to the driving signal.