How It Works; Field Of View; Distance & Spot Size - PeakTech 4975 Mode D'emploi

Contaminated batteries shall be marked with a symbol consisting of a
crossed-out refuse bin and the chemical symbol (Cd, Hg or Pb) of the
heavy metal which is responsible for the classification as pollutant:
1. "Cd" means cadmium.
2. "Hg" means mercury.
3. "Pb" stands for lead.
You can obtain further information about the Battery Regulations from
the Bundesministerium für Umwelt, Naturschutz und
Reaktorsicherheit (Federal Ministry of Environment, Nature
Conservation and Reactor Safety).

8. 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 displayed
on the unit. In units with a laser, the laser is used for aiming purposes
only.

8.1. 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.
8.2. 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. 2
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