Single-mode filtering and pupil remapping

Correction of the in.uence of phase corrugation in the pupil plane is a fundamental issue in achieving high dynamic range imaging. It can be done in real-time with a deformable mirror, but also by post-detection data processing. We present here an imaging system which, thanks to non-redundant pupil remapping and spatial filtering by single mode fibers, allows perfect calibration of the Modulation Transfer Function (MTF). Using phase closure, we have then precise knowledge of the complex values filling the spatial frequency plane of the telescope. We do show that such a system would be free from phase perturbations, photon noise limited, and would allow processed imaging with very high dynamic range. This at the price of loosing the convolution operation between the focal plane and the object.

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