距离是影响热红外测温精度的主要因素。为研究不同距离下不同热源强度的热红外测温精度, 设计野外实验, 布设 460 K和 505K两个热源温度, 分别在 20 m的距离以间隔为 1m的测温距离采集温度数据, 通过函数拟合, 分析不同距离下测温值与真实值之间的变化关系。结论如下: 1)随着距离的增加, 红外测温值呈现先急剧下降, 之后逐渐平缓至某一稳定状态的趋势, 且当热源温度越高, 达到这一稳定状态的距离就越长。 2)通过比较多项式和指数拟合函数的相关系数, 提出了基于指数函数的温度 -距离拟合关系, 相关系数最大为 0.999。3)依据温度变化速率提出温度 -距离的分段数学模型对测温数据进行误差补偿, 经过补偿后红外测温值与真实值最大相对误差仅为 0.59%。

In this study, field experiments were designed to determine the accuracy of thermal infrared temperature with different intensity heat sources at different distances. Source temperatures of two differ-ent heat intensities (460 K and 505 K) were set up, and temperature data were collected at distances rang-ing from 1.20 m using a sampling interval of 0.5 m. Furthermore, the relationship between the measured temperature and the actual value was analyzed, and the following conclusions were reached: 1)With an in-crease in distance, the infrared temperature value declined sharply at first, and then gradually became sta-ble; the higher the temperature of the heat source, the longer the distance required to reach the stable state. 2)By comparing the correlation coefficients of polynomials and the exponential fitting function, a temper-ature-distance fitting relationship based on the exponential function is proposed; the maximum correlation coefficient is 0.999. 3)The temperature-distance segmentation mathematical model is given based on the temperature change rate used to compensate the temperature measurement data; the maximum relative er-ror between the infrared temperature measurement and the true value was only 0.59% after compensation.