Pyrometers (infrared thermometers) use the heat radiation of objects invisible to the human eye to determine the temperature!

The thermometers presented in the previous articles must directly touch the object from which the temperature is to be determined. This can be a disadvantage in many cases, for example with very hot materials such as metal melts or corrosive liquids. In such cases non-contact measuring methods are used.

The so-called pyrometer (IR thermometer) detects the thermal radiation (infrared radiation) from objects, which each body emits due to its temperature (see article Black-body radiation). The radiation spectrum recorded by the measuring device thus allows conclusions to be drawn about the temperature of the objects. With the help of such a radiation measuring device, the object to be measured no longer has to be touched directly in order to measure the temperature.

Infrared thermometer (Pyrometer)
Figure: Infrared thermometer (Pyrometer)

Pyrometers (infrared thermometers) use the heat radiation of objects invisible to the human eye to determine the temperature!

Infrared thermometers are often equipped with a laser. However, this laser has only a targeting function. In this way, it is easier to determine the exact location from which the temperature is measured.