A case of non validity of MRTD concept

Krzysztof Chrzanowski

Abstract


MRTD is considered as the most important parameter of thermal imagers. It is a function of a minimum temperature difference between the bars of the standard 4-bar target and the background required to resolve the thermal image of the bars by an observer versus spatial frequency of the target. Both theoretical models and experimental tests presented in available literature show MRTD as a monotonically increasing bijective mathematical function. This paper presents results of measurements of MRTD that contradict this common opinion. These results show that in rare cases MRTD can be a non-bijective function. Imagers having such MRTD function can fulfill formal requirements on MRTD but will perform poorly at real life conditions.

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References
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Photonics Letters of Poland - A Publication of the Photonics Society of Poland
Published in cooperation with SPIE

ISSN: 2080-2242