热红外热像仪测量温度的误差分析和修正

ANALYSIS AND CORRECTION OF ERROR ON SURFACE TEMPERATURE OF GROUND OBJECT BY INFRARED THERMAL TRACER

红外热像仪具有非接触、精度高、直观、可实时大范围地观测表面温度的优势,对表面温度的测量研究较为适合。但由于环境和被测物体的材质、表面几何结构和观测角度的影响,会使成像上表现的温度测量值结果产生一定的误差。本文通过理论分析并结合多次使用热像仪进行公路热环境观测的经验.总结了野外应用热像仪进行精确测量时需要注意的问题和降低误差的手段,并借鉴遥感图像处理方法提出了对整幅热像的温度进行逐像元修正的方法.得到较好的订正效果。

The Infrared Thermal Tracer imaging the surface temperature in untouchable mode,by the principle of infrared image,is useful for measuring the surface temperature in a wide area and at the same time,which has an advantage in its higher precision and in its intuitional view. Because of the difference of measured surface,such as quality, surface situation, geometric structure and measured angle, the error of the temperature occurred in the image. On the basis of environmental investigation at a new section of the Expressway,the temperatures of road and vegetation protective slope were measured by the Infrared Thermal Tracer （TH3102MR） and the thermometers. By comparing the temperatures measured by infrared thermal tracer and measured by thermometers,the error of the temperature presented in the infrared ther- mal tracer needs to be corrected due to the situation of the measured surface and manner of the measured angle. The evaluation of temperature image from infrared temperature is usually calculated as the residual component of the surface energy balance. A simple and accurate correction,which determines the radiative ratio at one reference level, was found and assessed. The corrected method was used in temperature investigation of building envelope material, and good results are available. The infrared thermal tracer is useful for monitoring surface temperature of different material envelope and the temperature distribution due to its non-touch and imageable advantage.