半导体激光器温度调谐波长扫描技术

Temperature-tuning Based Wavelength Scanning Technology for Semiconductor Lasers

摘要:

低成本、小型化的波长扫描半导体激光器在光纤传感系统中有着重要作用。设计了一种可进行温度调谐的半导体激光光源驱动电路。该电路系统以ARM单片机作为控制中心,利用热敏电阻采样激光工作温度,并通过半导体制冷器(TEC)进行温度调节,使得激光器能够根据温度调谐实现波长扫描；同时通过背向光探测器(PD)采样激光输出功率,并通过改变半导体激光驱动电流实现对激光输出功率的控制,使得激光器在温度变化时输出光功率保持稳定。实验结果表明,该电路能够长时间可靠地工作,激光器能够实现的最大波长调谐范围为5nm,且输出光功率在整个波长扫描过程中保持稳定。

Abstract:

Low-cost and miniaturized semiconductor lasers play an important role in optical fiber-sensing system. In this paper, a design of semiconductor laser driving circuit for temperature tuning is experimentally presented. Using the ARM chip as the core controller, the design applies a thermistor to collect the temperature signal, and uses the thermoelectric cooler (TEC) to control the temperature, thus the wavelength scanning of the laser can be achieved by temperature-controlled tuning. Then the output power is collected by a photo diode (PD), and the optic power of the laser is controlled by electric current, so that the optic power can keep stable with the changing temperature. Experiments results show that the circuit can work reliably for a long time, the max temperature tuning range reaches 5nm, and the output optical power remains stable during the whole wavelength scanning process.