ARMY
NATO STANDARDIZATION AGREEMENT
(STANAG)
MEASUREMENT OF THE MINIMUM RESOLVABLE TEMPERATURE DIFFERENCE (MRTD) OF THERMAL CAMERAS
Annex: MRTD Results Sheet
Related Documents: None
AIM
1. This STANAG serves to establish the conditions under which the minimum resolvable temperature difference (MRTD) of thermal imagers is to be measured at a given temperature and in the centre of the field of view.
VALIDITY
2. The measurement procedure described applies only to thermal imagers where the MRTD concept is defined, i.e. for properly sampled systems. The applicable spectral ranges are 3 - 5 μm or 8 - 14 μm respectively or parts of these ranges.
AGREEMENT
3. Participating nations agree that the measurement procedure established in the following paragraphs will apply when measuring MRTD of thermal imagers.
DEFINITION OF MRTD
4. The MRTD is the minimum temperature difference which allows an observer to resolve a test pattern in accordance with a given criterion. MRTD is a function of spatial frequency of the test pattern. It depends on the measurement temperature, and may depend on the orientation of the test pattern.
NOTE 1 : The MRTD measured at a given temperature can be converted to the MRTD at other temperatures, if necessary. The conversion factor depends on the spectral response of the thermal imager and has to be determined in each case.
