| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor laser drive circuit in which a stable bias current can be flowed into semiconductor laser without installation of a bias current supply circuit and also without being affected by temperature change or aging of a current control circuit.SOLUTION: A semiconductor laser drive circuit includes: a constant current source 1 which flows a constant current; a semiconductor laser 2 whose one end is connected to one end of the constant current source: a resistance part 4 whose one end is connected to one end of the constant current source and includes one or more of variable resistances; a current control element 3 whose main electrode is connected to the other end of the resistance part; a current control circuit 6 which controls the current by applying a control signal to a control electrode of the current control element and then turning on/off the current control element; and a resistance value control circuit 5 which controls a resistance value of one or more of variable resistances in the resistance part. |
