How It Works - PeakTech 4970 Bedienungsanleitung

Field of view: Make sure, that the target is larger than the unit´s
spot size. The smaller the target, the closer your should be to it.
When accuracy is critical, make sure, that the target is at least
twice as large as the spot size..

7. How it Works

Infrared thermometers measure the surface temperature of an
object. The unit´s optics sense emitted, reflected and transmitted
energy, which is collected and focused onto a detector. The unit´s
electronics translate the information into a temperature reading
which is display on the unit.
7.1. Field of View
Make sure that the target is larger than the unit´s spot size. The
smaller the target, the closer you should be to it. When accuracy is
critical, make sure the target is at least twice as large as the spot
size.
7.2. Distance & Spot Size
As the distance (D) from the object increases, the spot size (S) of
the area measured by the unit becomes larger. See Fig.
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