optris PI 400 LW, Operator'S Manual

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optris PI LightWeight Kit
– E2013-04-B
48
For the measurement of “thermal radiation” infrared
thermometry uses a wave-length ranging between
1 µ and 20 µm.
The intensity of the emitted radiation depends on the material.
This material contingent constant is described with the help
of the emissivity which is a known value for most materials
(see enclosed table emissivity).
Infrared thermometers are optoelectronic sensors. They calculate
the surface temperature on the basis of the emitted infrared radiation
from an object. The most important feature of infrared thermometers is
that they enable the user to measure objects contactless. Consequently,
these products help to measure the temperature of inaccessible or
moving objects without difficulties. Infrared thermometers basically
consist of the following components:

lens

spectral filter

detector

electronics (amplifier/ linearization/ signal processing)
The specifications of the lens decisively determine the optical path of the infrared thermometer, which is
characterized by the ratio Distance to Spot size. The spectral filter selects the wavelength range, which is
relevant for the temperature measurement. The detector in cooperation with the processing electronics
transforms the emitted infrared radiation into electrical signals.
The electromagnetic spectrum and the area
used for temperature measurement