The important factors that ensure the accuracy of infrared thermometers are emissivity, distance to the spot, position of the spot, and field of view. Through communication and consultation with infrared temperature measurement experts and technical personnel from equipment manufacturers, and through multiple methods of repeated practice, a set of calibration equipment was self-made based on the principle of blackbody furnace. The feasibility of self calibration and comparison of this method was verified through comparison. Complete the comparison of basic errors, the influence of measurement distance changes, and the determination of emissivity range on time during self calibration. Before testing, adjust the infrared thermometer to a good state before using it for on-site testing.

Referring to the principle of blackbody furnace and practical work experience, the comparison standard used in self calibration is a self-made simple blackbody water tank with a size of 450 mmx300 mm, made of iron sheet and equipped with an electric heater inside. Use a Class 1.5 pressure thermometer with good stability (which can be replaced by a calibrated liquid glass thermometer) as a standard to test the temperature inside the water tank. Considering that when measuring the surface temperature of most organic materials, paints, or oxidized surfaces, black tape or flat black paint should be applied to the tested surface to compensate. When the black tape or black paint reaches the same temperature as the substrate material, measure the temperature on the surface of the tape or paint, Work experience with real temperatures. At the same time, considering the spot positioning test, use 80 mmx80 mm black tape to stick it on the liquid level at the same depth as the pressure thermometer probe. After the water in the water tank boils for 5 minutes and the temperature field in the water tank is uniform, use an infrared tester to aim at the center point of the black tape for comparison.