采用半导体激光器自身pn结特性测温的半导体激光器恒温控制

Constant Temperature Control of Semiconductor Laser Based on Temperature Characteristics of pn Junction

温度对半导体激光器的发射波长有很大的影响,而很多应用都要求半导体激光器的发射波长是稳定的。针对使用测温元件作为温度传感器进行半导体激光器恒温控制中存在的温度误差,提出了以半导体激光器自身pn结作为温度检测元件进行半导体激光器恒温控制的方法,设计了半导体制冷器的驱动电路。该方法利用pn结的温度敏感特性,首先通过实际测量标定pn结的温度与其两端压降的对应关系,然后通过测量压降得出相应的实际温度。实验结果表明,采用该方法消除了使用温度传感器进行半导体激光器恒温控制中温度梯度造成的恒温误差,提高了测量速度,显著减小了超调量,消除了静差和波动。

Since the temperature has a great effect on emission wavelength of semiconductor laser device, con- stant temperature control is necessary to the situation which require high wavelength stabilization. In view of temperature error in constant temperature control of semiconductor laser by means of temperature sensor, a new method taking pn junction of laser diode （LD） itself as temperature detector to achieve the goal of constant temperature was proposed. The drive circuit of semiconductor refrigerator was designed also. This method makes use of the temperature sensitive characteristic of pn junction to test the temperature of pn junction through its terminal voltage. The experiment results showed that the temperature error caused by temperature gradient is eliminated; the experiment speed is increased; the overshoot value is reduced distinctly; and the static error and fluctuation were also eliminated.