The magnetic field is one of the most important parameters in solar physics, and a polarimeter is the key device to measure the solar magnetic field. Liquid crystals based Stokes polarimeter is a novel technology, and will be applied for magnetic field measurement in the first space-based solar observatory satellite developed by China, Advanced Space-based Solar Observatory. However, the liquid crystals based Stokes polarimeter in space is not a mature technology. Therefore, it is of great scientific significance to study the control method and characteristics of the device. The retardation produced by a liquid crystal variable retarder is sensitive to the temperature, and the retardation changes 0.09 per 0.1 C. The error in polarization measurement caused by this change is 0.016, which affects the accuracy of magnetic field measurement. In order to ensure the stability of its performance, this paper proposes a high-precision temperature control system for liquid crystals based Stokes polarimeter in space. In order to optimize the structure design and temperature control system, the temperature field of liquid crystals based Stokes polarimeter is analyzed by the finite element method, and the influence of light on the temperature field of the liquid crystal variable retarder is analyzed theoretically. By analyzing the principle of high-precision temperature measurement in space, a high-precision temperature measurement circuit based on integrated operational amplifier, programmable amplifier and 12 bit A/D is designed, and a high-precision space temperature control system is developed by applying the integral separation PI temperature control algorithm and PWM driving heating films. The experimental results show that the effect of temperature control is accurate and stable, whenever the liquid crystals based Stokes polarimeter is either in the air or vacuum. The temperature stability is within 0.015 C, which demonstrates greatly improved stability for the liquid crystals based Stokes polarimeter.

磁场是太阳物理学中最重要的参数之一，而旋光仪是测量太阳磁场的关键设备。基于液晶的斯托克斯旋光仪是一项新技术，将应用于我国研制的第一颗天基太阳观测卫星——先进天基太阳观测站的磁场测量。然而，基于液晶的太空斯托克斯旋光仪并不是一项成熟的技术。因此，研究该装置的控制方法和特性具有重要的科学意义。液晶可变延迟器产生的延迟对温度很敏感，每0.1℃延迟变化0.09。这种变化引起的偏振测量误差为0.016，影响磁场测量的准确性。为保证其性能的稳定性，本文提出了一种基于液晶的空间斯托克斯旋光仪高精度温度控制系统。为了优化结构设计和温度控制系统，采用有限元法对基于液晶的斯托克斯旋光仪的温度场进行了分析，从理论上分析了光对液晶可变延迟器温度场的影响。通过分析空间高精度测温原理，设计了一种基于集成运放、可编程放大器和12位A/D的高精度测温电路，采用积分分离PI温控算法和PWM驱动加热膜，研制了高精度空间温控系统。实验结果表明，基于液晶的斯托克斯旋光仪无论是在空气中还是在真空中，温度控制的效果都是准确和稳定的。温度稳定性在 0.015 摄氏度以内，这表明基于液晶的斯托克斯旋光仪的稳定性大大提高。