Infrared Thermometer
size (S). The ratio between these values is fixed at 12:1. For example at
1metre the spot size is 84millimetres wide, at 1.5 metres the spot size is
125millimetres.
For accurate readings the target should be larger than the visual spot size
and should fill the field of view as indicated by the laser dots.
For small targets you may have to be quite close.
Emissivity
Emissivity is a crucial part of obtaining accurate and repeatable readings.
Emissivity is a complex and difficult area. Objects made of different
materials and with different surface finishes will have different emissivities.
Emissivity also varies with frequency, some objects are transparent to
certain frequencies but opaque to others.
In the case of the MS6530 the emissivity is fixed at 0.95. Most organic
materials and metal surfaces range between 0.85 and 0.98. 1.0 would
be a theoretically perfect object, reflecting all the energy that fell on it.
The result is that if the emissivity of an object measured with the MS6530
is less than 0.95 the reading will also be less than the true temperature of
the object. If the emissivity is more than 0.95 the reading will be higher
than the true temperature.
Note that shiny or polished surfaces have low emissivity so your readings
may also be correspondingly low.
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