Adaptive optics solutions for turbulence mitigation in different scenarios

Several studies on different adaptive optics concepts are presented in the article. Each one of the procedures shows its peculiar advantages when considering different situations where the image distortion, due to atmospheric or artificial turbulence, becomes problematic. A setup is presented based on the usual wavefront reconstruction techniques using a Shack-Hartmann wavefront sensor in a closed loop with a deformable mirror and a computer. The reconstruction method follows the modal approach which has been demonstrated to be more robust and suitable than the zonal one when limited to the correction of the first Zernike components1 . Some results deriving from the studies are reported. A second part in the article describes the measurements and the characteristics of the atmospheric turbulence present in direct tests. Another procedure based on the control of a deformable mirror by mean of a fast iterative procedure is also treated and the relative results about the compensation of laser beams as well as extended images are shown.

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