Patent ID: 6977949

Claim:
An optical output control circuit of a semiconductor laser comprising: the semiconductor laser receiving a modulating electric current and a bias electric current; modulating electric current supplying means for supplying said modulating electric current on the basis of an inputted modulating signal; and bias electric current supplying means for supplying said bias electric current, wherein first temperature correcting means for increasing said modulating electric current with a rise in ambient temperature is arranged in said modulating electric current supplying means, a second temperature correcting means for increasing said bias electric current with said rise in ambient temperature is arranged in said bias electric current supplying means, a feedback circuit negatively fed back by said bias electric current is arranged in said bias electric current supplying means, said first temperature correcting means is constructed by a first resistor circuit constructed by a first thermistor, a first resistor connected in series to said first thermistor, and a second resistor connected in parallel to said first thermistor, and is also constructed by a third resistor connected in series to said first resistor circuit, said second temperature correcting means is constructed by a second resistor circuit constructed by a second thermistor, a fourth resistor connected in series to said second thermistor, and a fifth resistor connected in parallel to said second thermistor, and is also constructed by a sixth resistor connected in series to said second resistor circuit, said modulating signal is inputted between both terminals of said first temperature correcting means, a direct current voltage is applied between both terminals of said second temperature correcting means, said modulating electric current is supplied by the modulating signal outputted between said third resistor and the first resistor circuit, and said bias electric current is supplied by a divided voltage outputted between said sixth resistor and the second resistor circuit.