A METHOD OF PROCESSING MEASUREMENT DATA HAVING ERRORS DUE TO UNPREDICTABLE NON-UNIFORMITY IN ILLUMINATION OF DETECTORS

A method for reducing error (when compared to conventional methods) in estimates of radiance inferred from measurements of irradiance provided by detectors in an array of a sensor. By using measurement data from each cluster in a set of nested clusters in the neighborhood of a selected detector and applying selected mathematical relationships, an accurate estimate is obtained. A source of this error springs from the non-uniformity of illumination that occurs within the finite solid angle field of view (FOV) of a detector in a sensor array due, at least in part, to intrinsic unpredictable characteristics of the scene being viewed by the sensor array. To achieve fine resolution with reasonably sized detector FOVs, this non-uniformity makes impractical the use of average values of illumination within the solid angle defining the detector's FOV, the conventional method for deriving estimates of radiance.