Performance of active and passive night viewing systems under low ambient illumination levels

Abstract

A comparison of the estimated field performance of some typical active and passive night viewing systems under low illumination levels is presented. In addition to the ‘range’, a generalized figure of merit, the minimum detectable object size (MIDOS), is suggested and used as a basis of comparison. The influence of the optics and other parameters is discussed and the usefulness of the results in the optimization of system design is illustrated. The results indicate that active systems perform better than similar passive systems under certain commonly encountered ambient conditions.