Wavelength dependence of blur-circle size through turbulent flow
Michele R. Banish, Rodney L. Clark, Alan D. Kathman · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1990
Aerodynamic flow surrounding a missile or aircraft in flight can degrade the performance of on-board optical sensor systems. The minimum resolvable spot or blur circle is a measure of optical system performance. The blur circle size may change by orders of magnitude throughout the course of the vehicle flight trajectory due to aerodynamic perturbations. This paper examines the wavelength dependence of blur circle size. It is shown that in many cases an optimum wavelength exists at which the blur circle size is minimized. Expressions are given for depicting the Point Spread Function shape and wavelength at which blur is minimized. The optimization expressions presented are suitable for use on a desk top computer or calculator.