Thermal imaging is defined as the detection of a radiating object by an infrared sensor in the short-wave (SWIR), medium-wave (MWIR) and long-wave (LWIR) bands of the infrared spectrum. An object with a temperature higher than absolute zero radiates. The ability to detect this radiation depends on the type of sensor used, the temperature and the emissivity of the object. The higher the temperature of the object, the higher the radiation. If the temperature of an object is higher than 150 degrees Celsius, SWIR cameras are an excellent tool for detecting this radiation.

As can be seen in the three videos below, when the hot air gun and the soldering iron start to be heated, this temperature change can be easily seen in the SWIR camera as the temperature increases.