How it works

Any object with a temperature greater than 0 Kelvin emits thermal radiation, the intensity and position of the emission maximum of which depends on its temperature. This radiation is detected by the IR sensor (pyrometer). The radiation spectrum recorded by the sensor thus allows conclusions to be drawn about the temperature of the object. With the help of an IR temperature sensor, the object to be measured no longer needs to be touched directly in order to record the temperature.

Different materials also have different emission factors and therefore emit IR radiation with a different intensity at a given temperature. In temperature measurement, this is especially important for objects that are IR-opaque and have a low emission factor. An object made of polished stainless steel has a much lower emission factor than the same object with a rough surface.

In addition to the composition and surface texture of an object, a third factor indirectly affects the emission factor, the spectral range of the sensor. It does not directly affect the object, but it does affect how the sensor perceives the spectrum emitted by the object. Materials that are partially transparent, such as glass, plastics or silicone, can be measured in a range in conjunction with the appropriate selective filters.