Laser beams used in many open space applications, such as in defense, optical communication, and remote sensing, will subject to turbulence distortions that disrupt the intended beam profiles at the end of propagation. To guide the transmitted beam properly through an open space channel, adaptive optics (AO) are often used to implement beam corrections based on the reciprocity principles. In specific, if wave distortion from a remote spot can be determined and field conjugated at the site of the transmitter, the transmitted light will focus to the same spot at the receiver. Many experiments have demonstrated such a principle using a cooperative laser guide star on the target plane. However, finding or creating a well-defined guide star is impractical in real-world applications. The second best beacon choice is temporal glint signals that are relatively refined in geometry and brighter than ambient target illumination. To date, the best approach to extract information from arbitrary glint signals to instruct AO correction is still unknown. We propose the plenoptic sensor technique to extract phase distortion information from glint signals with minimum loss of information. In addition, as the addressed turbulence channel is typically a lateral path near the ground, we also validate the function of the plenoptic sensor in revealing the anisotropic state of turbulence.
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