Measuring system performance characteristics of infrared systems (MRT, MTF, NETD) using automatic test equipment

Abstract

A project is described whose goal is to develop and test image signal processing algorithms and techniques that allow automation of MRT (minimum resolvable temperature) testing. The basis of the automated test system is the premise that the system MTF (modulation transfer function) is a product of the MTFs of each subsystem component. The MTF of the lens and detector are the major factors affecting system MTF. Therefore, for a given forward-looking infrared system, if the detector and lens system remain constant, the system MTF should be constant. Thus, the results of an automated measurement of the system MTF will remain constant relative to the MTF measurement obtained from human observers. If the constant is proven valid, then it can be reasoned that for all subsequent units of identical design, a constant can be applied to allow verification of system critical parameters to be conducted using automated methods of testing with the same or nearly the same confidence levels compared to the older manual methods. This set of data would be far more repeatable and correlate closer to actual field results. The use of a qualified, quantifiable, and repeatable constant results in a more realistic assessment of actual performance and the removal of human subjectivity from the equation. >