高精度大范围的光学晶体温度控制系统

High-precision and wide-range optical crystal temperature control system

为解决固体激光器工作时光学晶体产生的热沉积问题,保证其工作性能稳定,提出了一种基于半导体制冷器(TEC)的高控温精度、大控温范围光学晶体温度控制方案。分析了TEC的工作特性和光学晶体的热效应与传热机理,将TEC工作过程中自身温度变化引起的电气特性改变与光学晶体温度的变化同时纳入控制环节,建立了温度-电流双闭环温度控制模型,设计并完成了一套高控温精度、大控温范围的光学晶体温度控制系统。实验结果表明:本系统在-15~120℃的温度控制范围内,可以迅速稳定在任一设定的温度点,其控温精度优于±0.002℃;当设定温度和实际温度之间的偏差在20℃以内时,其收敛稳定时间小于60s,可以满足固体激光器中光学晶体对控温范围与精度的要求。

To address the problem of heat accumulation of optical crystals in solid-state lasers and ensure the stability of its work performance,a temperature-control method with high temperature control accuracy and large temperature control range,based on a semiconductor Thermoelectric Cooler（TEC）,was proposed.Based on the operating characteristics of the TEC,the heat effect and the heat transfer mechanism of the optical crystal,a temperature-current double closed-loop temperature control model was established.The proposed model controls both the electrical characteristic variations of the working TEC and the temperature variations of the optical crystal.A high-precision and wide-range optical crystal thermostat control system was designed and implemented.Experimental results demonstrate that the overall temperature control accuracy of the proposed systemis better than ±0.002 ℃,and the system can quickly stabilize at any set point temperature in a wide temperature range of-15—120 ℃,when the set temperature and the actual temperature deviate20 ℃,a stable convergence time of less than 60 s,which meets the requirements of solid-state laser optical crystal for temperature range and accuracy.