基于TEC温控的非制冷热红外测温系统的研究与实现

Research and Implementation of Uncooled Thermal Infrared Temperature Measurement System Based on TEC Temperature Control

摘要: 非制冷红外热像仪用于人体或者其他精准测温场景使用时，需要具有较高的测温精度，然而受外界环境温度变化和自身芯片发热的影响，会产生较为严重的温度漂移现象，从而导致测温精度受到一定的影响。为了消除这一影响，本文采用TEC作为非制冷探测器的制冷方案，通过Xilinx XC7A100T FPGA主控芯片合理设置带TEC的国产氧化钒红外探测器焦平面温度，实时检测探测器内部温度实现闭环高精度温控，使红外探测器尽可能工作在恒温状态。在完成基本成像的基础上，使用探测器原始数据计算并研究在5℃到55℃环境温度下打开温控和关闭温控条件下对测温精度的差异，实验结果为探测器在打开和关闭温控条件下测温精度平均为0.5℃和1.3℃，结果表明利用TEC对红外探测器做恒温控制有利于提高探测器原始数据的稳定性，可以一定程度提高测温精度。

Abstract: When the uncooled infrared thermal imager is used in the human body or other precise temperature measurement scenarios, it needs to have a high temperature measurement accuracy. However, due to the influence of the changes in the external environment temperature and the heating of its own chip, a relatively serious temperature drift phenomenon will occur, which will lead to a certain impact on the temperature measurement accuracy. In order to eliminate this effect, this paper uses thermoelectric cooler (TEC) as the refrigeration scheme of the uncooled detector, reasonably sets the focal plane temperature of the domestic vanadium oxide infrared detector with TEC through the Xilinx XC7A100T Field-Programmable Gate Array (FPGA) master chip, and real-time detects the internal temperature of the detector to achieve closed-loop high-precision temperature control, so that the infrared detector can work at a constant temperature as much as possible. On the basis of completing the basic imaging, the original data of the detector is used to calculate and study the difference in the temperature measurement accuracy under the conditions of opening and closing the temperature control under the ambient temperature of 5˚C to 55˚C. The experimental results show that the average temperature measurement accuracy of the detector under the conditions of opening and closing the temperature control is 0.5˚C and 1.3˚C. The results show that using TEC to control the temperature of the infrared detector is conducive to improving the stability of the detector’s original data and can improve temperature measurement accuracy to a certain extent.