目标表面发射率对红外热像仪测温精度的影响

介绍了红外热像仪测温原理,分析了影响红外热像仪测温精度的因素,计算了不同表面发射率下红外热像仪的测温误差曲线。理论分析表明,目标表面发射率越高,红外热像仪测温精度越高。实验改变表面发射率的设置,计算了不同表面发射率对应的总辐射亮度,得到TP8型长波红外热像仪能够精确测温时,目标表面发射率必须大于0.5的结果。最后,对表面发射率分别为0.96、0.93和0.3的3种材料进行实际测温,结果表明,材料表面发射率较高时,红外热像仪具有较好的测温精度。

Influence of surface emissivity of objects on measuring accuracy of infrared thermal imagers

The theory of temperature measurement by infrared imagers is introduced and the factors that influence the accuracy of infrared temperature measurement are analyzed. The error curves of temperature measurement at different surface emissivities are given. Using theoretical analysis, it is shown that the higher the surface emissivity of an object is, the more accurate the measuring accuracy of imager is. By changing the setting of surface emissivity, the corresponding total radiance luminance to surface emissivity is calculated. Analysing the results, the conclusion indicates that TP8 long wave thermal infrared imager can measure the temperature accurately when the surface emissivity is above 0.5. Finally, three materials whose surface emissivity is 0.96, 0.93 or 0.3 are measured, respectively, and the result shows that a higher surface emissivity leads to a better temperature measuring accuracy.