The emission factor is the rate of energy emitted from the surface of the object in front of the probe. All objects possess a particular emission factor which changes according to the object’s conditions or temperature. Since the probe allows the emission factor to be set, even more precise measurements can be conducted by matching the emission factor of the object to be measured.

Objects with a low emission factor (e.g the surface of shiny metallic objects) reflect the surrounding temperature since they are reflective. In this case, it is necessary to block out these effects from the surrounding objects since incorrect measurements will result by reflecting these temperatures.

The emission factor normally has a maximum value of 1.00. However, taking into consideration the influence of the surrounding noise, the emission factor of the probe can be set up to 1.20.