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MEASUREMENT CONSIDERATIONS
1. Theory of Measurement
Every object emits infrared energy in accordance with its temperature. By
measuring the amount of this radiant energy, it is possible to determine the
temperature of the emitting object.
2. About Infrared
Infrared radiation is a form of energy (electromagnetic radiation), and has the
property that it passes easily through air while it is easily absorbed by solid
matter. With an emission thermometer, which operates by detecting infrared
radiation accurate measurement is possible, irrespective of the air tempera-
ture or the measurement distance.
3. Emission Thermometer Structure
Infrared radiation which has been emitted from the object is focused upon an
infrared radiation sensor, via an optical system. This includes a lens which is
transparent to infrared radiation, and a 5.3µm cut off filter. The output signal
from the infrared radiation sensor is input to an electronic circuit along with the
output signal from a standard temperature sensor (Thermopile).
