1. The object's reflectivity, as the reflective metal surface has high reflectivity that will cause lower measured temperature;
2. The temperature of the radiation background, the influence will be small if there is no clouds, otherwise it will bring great influence in temperature measurement.
3. The influence from the air factors including temperature and humidity. The higher these two factors, the easier to affect the temperature measurement of the object and lead to low accuracy.
4. The thickness of the air, also the distance from the camera to the measured object. The further the distance, the greater the influence from the air, and less the accuracy of the measurement.