AUTOCORRELATION HOLE IN NONLINEAR IMAGE DETECTORS - AN ESTIMATE USINGAN AUXILIARY PHOTOMULTIPLIER

In an experiment in which two or more photoevents arriving at the same pixel are considered as a single count, a one-pixel-sized central hol e appears in the autocorrelation estimate. This hole is a source of er ror when high-resolution techniques based on the autocorrelation funct ion are applied to image or signal recovery. We present an experimenta l method with which to evaluate the autocorrelation central hole based on the simultaneous measurement of the total number of counts in the image detector and an auxiliary photomultiplier. The technique is easy to perform and provides high accuracy. (C) 1995 Optical Society of Am erica