Design of an imaging system for turbulence mitigation using phase diversity
conference paper
Long range observation through atmospheric turbulence is hampered by spatiotemporally randomly varying shifting and blurring of scene points in recorded imagery. The image quality degradation induced by turbulence will limit the performance of the system. To mitigate the effect, various hardware strategies combining wavefront sensors together with adaptive optics have been proposed. Both components are associated in a control loop designed to compensate in real time for the aberrations induced by turbulence and reach a system performance close to the diffraction limit. Those techniques are designed for observations of punctual sources within a narrow field of view under which the effect of turbulence can be considered as spatially constant. Unfortunately, the majority of long range horizontal path imaging applications deal with extended sources that are wider than the area under which the turbulence effect is assumed constant. For long range horizontal observation, we devise here a method implementing wavefront sensing using a high speed camera. The system relies on two images of the same scene and same atmosphere realization, having one of the images distorted by a controlled aberration. We describe the simulation and the design choices made for the implementation of such a system. We show that this method allows to measure the relevant shape of the wavefront and provides a way to correct for the effect of atmospheric turbulence.
TNO Identifier
991033
Publisher
SPIE
Source title
Proc. SPIE 12737, Electro-Optical and Infrared Systems: Technology and Applications XX, 127370A
Files
To receive the publication files, please send an e-mail request to TNO Repository.