CI Systems ControlMaster SR-800R, Руководство по эксплуатации

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CI Systems SR-800R
3.2.3.5 MRTD
The SR-800R provides the ability to run a semi-automatic MRTD Test.
MRTD (Minimum Resolvable Temperature Difference) is the equivalent Blackbody
temperature difference between a standard target at a given spatial frequency and its
background, such that, the target is "just resolved" by the observer.
In this test, the observer typically looks at a sequence of 4-bar targets at different
spatial frequencies (see
Figure 3-18 ). An MRTD curve is drawn as a function of the
spatial frequency.
NOTE
"Just resolved" is the term used for the particular point at
which, in the eyes of the observer, there is a transition between
being able to resolve the target's individual features, and not
being able to resolve them.
Figure 3-18: MRTD - Typical 4-Bar Targets
3.2.3.5.1 Using Radiometric Offset in MRTD Tests
The Radiometric Offset can be used to shorten the duration of MRTD Tests.
A Radiometric Offset is defined as a constant temperature deviation added,
artificially, to the real Blackbody differential temperature.
This feature is used to compensate an error in FLIR interpretation of infrared scenes.
These can be caused by phenomena such as: minute differences in the emissivity of
the Blackbody emitter versus a target due to the "Cavity Effect" on the emitter.
The effect is interpreted as an apparent temperature difference.
605-7040 Operation Manual
Rev D
3-20
June 2013
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