Principle Of Operation - Ametek LAND UNO User Supplement

User Supplement
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Principle of Operation

Fig. 1 shows the field of view for a standard UNO Thermometer. The axis of
the field of view is fixed at the centre of the thermometer lens and is at right
angles to the front face of the thermometer.
Fig. 2 shows the field of view for a Thermometer fitted with the Target
Orbiting (TO) option. The target spot diameter at any given distance is
identical to that of the corresponding standard Thermometer.
field of view rotates about a 'cone' of half-angle 2°. This 'cone' is at right
angles to the front face of the thermometer. The axis of the cone passes
through the centre of the thermometer lens.
The field of view rotates three times per second.
The Target Orbiting option is designed for use on moving or intermittent
targets. In a standard UNO Thermometer, the eyepiece graticule defines the
target spot diameter. In a Target Orbiting Thermometer, the graticule defines
the orbit of the centre of the target spot (refer to Fig. 3).
When viewing a narrow, moving object (e.g. wire) there may be some to
lateral movement of the product with respect to the thermometer. This
means that it is possible that the target may not be covered by the graticule
for considerable periods.
A Target Orbiting Thermometer can be sighted so that the graticule covers the
limits of lateral movement. This means that an accurate, valid temperature
reading will be obtained by the thermometer at least three times per second.
Fig. 3 Comparison of views through the eyepiece (Standard v Target Orbiting
Limits of lateral
movement
Non target orbiting
Thermometer
Target Orbiting Thermometer
However, the
Limits of lateral
movement
Target orbiting
Thermometer
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