The two-color temperature measurement will not change with the state of the surface of the object (the surface roughness is different, or the surface chemical state is different), it will not affect the accuracy of the temperature measurement, and the single-color thermometer will have an effect.

The optical part of the thermometer, such as glass, will leave some dust after using it for a period of time. Water, gas, oil, etc. in the air will reduce the emissivity coefficient. reduce. Two-color thermometers measure the ratio of objects in specific two bands. When dust, water vapor, etc. appear, the measured signals in the two bands decrease at the same time. After division, the ratio does not change. However, this does not mean that maintenance is not required when using a two-color thermometer. When dust, water vapor, etc. are too dirty, the glass still needs to be wiped.

Monochrome thermometers cannot measure objects smaller than the field of view. When the target cannot fill the field of view, the measurement temperature will be low. The two-color thermometer can measure objects smaller than the field of view.