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).