Refraction measurements and modeling over the Chesapeake Bay during the NATO (TG-51) SAPPHIRE trials, June 2006

Optical refraction tends to occur frequently in the atmospheric boundary layer. Due to a gradient in the temperature as function of height, rays are bending down towards the earth (super-refraction), or up towards to the sky (sub-refraction). As a consequence, images of targets at long range may be distorted and mirages may occur, while the...

Geometrical image distortion and aberration for long-range targets in a non-homogeneous atmosphere

When images are made of distant targets over long atmospheric paths, local variations of the refractive index of the air may lead to severe optical distortions and aberrations. An extreme example of such variations is the stream of hot exhaust gases on ships. The performance of infrared and optical sensors, mounted on elevated platforms on board...