基于半导体激光器高精度恒温系统设计

摘要

为了在宽温环境中保证半导体激光器能够稳定地输出功率和波长,针对半导体激光器体积小、重量轻及对温度稳定性要求高等特点,在采用负温度系数热敏电阻作为温度传感器并对其输出信号进行处理的基础上,设计了基于微控制单元的半导体激光器温度控制系统,并在软件上采用了直接比例积分微分算法等方法.通过微控制单元调整输出调制信号脉宽和幅值,从而改变半导体致冷器的驱动电流的大小和方向,并进行了相应理论分析和实验验证,可知半导体激光器工作温度稳定在25℃左右,且温度稳定精度为±0.1℃.结果表明,该高精度温度控制系统在宽温环境中控制精度高、响应速率快,优于其它同类产品.%In order to obtain stable output power and wavelength from a semiconductor laser in a large range of temperature, according to the characteristics of small volume, light weight and the high requirement of temperature stability of a semiconductor laser, with a negative-coefficient heat-sensitive resistance as a temperature sensor, a temperature control system was designed based on a micro control unit ( MCU) and direct proportion-integration-differentiation ( PID ) algorithm. Changing the width and amplitude of the pulse width modulation signal output from the MCU to adjust the driving current and direction of the thermoelectric cooler, the temperature of the semiconductor laser was controlled at about 25℃ ± 0. 1℃. Experimental results show that the temperature control system is with high precision and fast responsibility in a large range of temperature, it is better than other similar products.