Development of automated procedures for expedient and cost-efficient acceptance testing of imaging infrared systems

An improved acceptance test procedure for imaging infrared (IIR) equipment has been developed to remove subjectivity, improve repeatability, and decrease the time and expense over existing methods. Traditional procedures for acceptance testing of IIR equipment require manual minimum resolvable temperature difference (MRTD) measurements at multiple spatial frequencies with both positive and negative contrast targets. Although the manual measurement of MRTD is the standard evaluation technique used in developmental testing, it is deficient for use as an acceptance test. The main limitations are subjectivity, length of time required, and manpower (i.e., cost). The Missile Guidance Directorate (MGD) of the U.S. Army Aviation and Missile Research, Development, and Engineering Center has developed the automated infrared sensor test facility (AISTF) to perform automated acceptance tests and remove the subjectivity of the test procedure. The AISTF measures the modulation transfer function, noise equivalent temperature difference, 3-dimensional noise analysis, field-of-view, and non-subjective MRTD of the unit under test (UUT). The software interface for the AISTF provides an efficient means for a single test conductor to set up and conduct the test. The software controls the experiments by selecting the appropriate target, setting thermal contrast, acquiring digital imagery, and performing image analysis. Test results are provided in a detailed report and stored in a database. in addition to production line acceptance testing, the AISTF should be applicable to flight-line testing, R&D analysis, and sensor characterization.