Abstract

The currently used static minimum-resolvable-temperature-difference (MRTD) model for IR imaging systems, referred to as the Ratches model,¹ is severely limited in scope. In practice, the predictive MRTD does not match the measured MRTD. The cause of these discrepancies, which are generally referred to as the high- and low-frequency problems, can be traced to the limitations of the eye-brain model that is a part of MRTD. A recent work² has pointed out that eye-brain characteristics are not exponential functions, as most experts believe, but are sinusoidal functions.

© 1990 Optical Society of America