NONUNIFORMITY CORRECTION AND CORRECTABILITY OF INFRARED FOCAL-PLANE ARRAYS

Correction of photoresponse nonuniformity in infrared staring sensor a rrays is investigated. A general nonuniformity correction procedure is proposed. The procedure is based on multiple irradiation sources and on least square fit approximations to the individual pixel response ch aracteristics. Nonlinearities of the signal response are taken into ac count. A correctability figure of merit is defined which may be used t o estimate the residual fixed-pattern noise after correction. The corr ection procedure and the correctability are applied to a real data set measured by a 64 x 64 element infrared focal plane array (FPA). It is shown that an offset correction is insufficient for this data set and that a linear correction reduces the fixed-pattern noise contribution to the magnitude of the temporal noise background. The residual uncor rected fixed pattern noise can be related to pixels showing large temp oral noise.