半导体激光器高精度稳频输出控制系统

为了在光纤干涉仪中得到光源高精度稳频输出,采用高稳定度的恒温控制以及功率稳恒控制方法,通过高信噪比的运算放大器、半导体制冷器,设计了一种激光电源驱动系统,并进行了理论分析和实验验证。其能为半导体激光器提供温度控制精度在±0.01℃,制冷驱动电流可达800mA,同时使得半导体激光器输出波长控制精度在±0.1nm,驱动电流最大输出可达180mA,输出电流的稳定度为10-4~10-5。结果表明,该系统不仅结构简单,而且温度控制稳定、准确度高,可使半导体激光器的输出波长保持稳定,保证了干涉型光纤传感器的测量准确度以及在通信领域中的应用。

Accurate controlling system for the output and frequency of laser diodes

The change of the output power and the frequency of the light source of an optical fiber interferometer seriously affects the output of the interferometer. In order to get high output accuracy and stability from the optical fiber interferometer,the operation amplifier with high S/N,and a semiconductor cooler were used. A laser power driving system was designed. Through theoretical and experimental analysis,it was proved to provide laser diode(LD)with high stability and,high temperature controlling precision of ±0.01℃. The cooling driving current could reach 800mA. At the same time,it provides current control with high stability and constant control over output power,which assures the precision of the controlled wavelength to be ±0.1nm.The maximum LD driving current reaches 180mA,and the output curren stability could be kept among 10－4～10－5. The experimental data indicate the method is not only simple,but also highly accurate and stable in terms of temperature control. The application maintains the output wavelength of the laser diode at a constant level and assures the measure accuracy in optical fiber interferometer sensors(OFIS)and optical communication.