An Environmentally Benign Helicopter Deicing/Anti-Icing Fluid

Atmospheric turbulence adversely affects imaging systems by causing a randomdistribution of the index of refraction of the air through which the lightpropagates. We show that tactical Army infrared sensing systems are not affected byturbulence in the same way as astronomical imaging systems, but the influence ofturbulence can still be quite strong. Rather, the shape of the point spread functionassociated with the scene varies significantly across the image field-of-view. Thiscondition is referred to as anisoplanatic imaging. Fortunately, the overall effectof turbulence within a given isoplanatic patch is not as strong as in theastronomical imaging case due to shorter optical paths and longer wavelengths. Tiltand low order turbulence modes will dominate the aberration experienced withinindividual isoplanatic patches, greatly simplifying the image reconstruction problem.In Phase I we demonstrated an approach for mitigating the type of aberrationsdescribed above. The results of the Phase I show that an approach based on blockmatching techniques is capable of significantly enhancing the resolution and removingthe distortions caused by the non-isoplanatic turbulence conditions. Thesedistortions and blurring are time varying and our demonstrated algorithm is effectivein removing these temporal effects. In Phase II we propose to develop and demonstratea hardware-based system for implementing in real time the image reconstructionalgorithm.