%0 Journal Article %T Improving wavefront sensing with a Shack-Hartmann device %+ Centre de Mathématiques et de Leurs Applications (CMLA) %+ CEntre de REcherches en MAthématiques de la DEcision (CEREMADE) %+ Centre National d'Études Spatiales [Toulouse] (CNES) %+ Departament de Tecnologies de la Informació i les Comunicacions %A Rais, Martin %A Morel, Jean-Michel %A Thiebaut, Carole %A Delvit, Jean-Marc %A Facciolo, Gabriele %A Thiebaud, Carole %< avec comité de lecture %@ 1559-128X %J Applied optics %I Optical Society of America %V 55 %N 28 %8 2016 %D 2016 %R 10.1364/AO.55.007836 %Z OCIS codes: (010.1080) Active or adaptive optics; (010.7350) Wave-front sensing;(220.1140) Alignment. (100.0100) Image processing. (110.4280) Noise in imaging systems %Z Computer Science [cs]/Image Processing [eess.IV] %Z Computer Science [cs]/Signal and Image Processing %Z Computer Science [cs]/Modeling and Simulation %Z Computer Science [cs]/Computer Vision and Pattern Recognition [cs.CV]Journal articles %X In order to achieve higher resolutions, current earth-observation satellites use larger lightweight primary mirrors that can deform over time, impacting on image quality. We evaluated the possibility of compensating these deformations directly in the satellite by combining a deformable mirror with a Shack-Hartman wavefront sensor (SHWFS). The performance of the SHWFS depends entirely on the accuracy of the shift estimation algorithm employed, which should be computationally cheap to be executed on-board. We analyzed the problem of fast accurate shift estimation in this context and propose a new algorithm, based on a global optical flow method that estimates the shifts in linear time. In our experiments, our method proved to be more accurate and stable, as well as less sensitive to noise than all current state-of-the-art methods, permitting a more precise on-board wavefront estimation. %G English %2 https://enpc.hal.science/hal-01829646/document %2 https://enpc.hal.science/hal-01829646/file/OSA-journal-template_preprint.pdf %L hal-01829646 %U https://enpc.hal.science/hal-01829646 %~ ENPC %~ CNRS %~ UNIV-DAUPHINE %~ ENS-CACHAN %~ CNES %~ CEREMADE %~ PARISTECH %~ TDS-MACS %~ PSL %~ UNIV-PARIS-SACLAY %~ ENS-CACHAN-SACLAY %~ UNIV-DAUPHINE-PSL %~ CMLA %~ FARMAN %~ ENS-PARIS-SACLAY