| Summary: | During the last ten to fifteen years, a new class of electronic imaging devices has been created. Closely related to the visible-light Charge-Coupled Device, or CCD, this new class of components has extended electronic imaging capability into the near, middle, and long-wave infrared regions of the electromagnetic spectrum. Most notable among these new components are the IRCCD, a monolithic device, and the hybrid imaging device, which employs separately optimized detector and readout assemblies. Since the creation of the first infrared imaging device, there has been a continual effort to improve performance. One of the many problems faced by the designers of such devices is that of spatial response nonuniformity. This investigation considers the impact of spatial response nonuniformity on thermal imaging. The analysis presented assumes the use of a platinum silicide hybrid imaging device intended to operate in the 3-5 μm middle-wave IR band. Both linear and nonlinear models for its operation are developed. Using these models, estimates of system performance are made. Post-correction spatial noise is estimated for two popular nonuniformity correction schemes. To demonstrate the validity of these concepts, results obtained from actual device testing are presented. Upper bounds are established for the amount of nonuniformity present in the tested device. To complete the investigation, conventional detector figures of merit are then modified to include the effects of nonuniformity.
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