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International audience; Innovative optical designs combing freeform optics and curved freeform sensors will be key elements to improve the optical performance and reduce the overall manufacturing and testing pressure of optical complex systems. In this paper, three version of unobscured all-reflective TMA-type telescopes (D=10cm, FOV=7°×7°) will be designed separately with flat sensor, spherical sensor and freeform sensor. Then, we will analyze and compare their imaging quality (RMS spot radius) and surface complexity (PV sag departure and Max slop departure) to demonstrate the advantage of freeform sensor applied in the off-axis optical system. Finally, we make comparison on sensitivity analysis of surface error between mirror surfaces and freeform sensor surfaces to prove that the manufacturing pressure of the sensor did not increase even though its surface complexity increased. We expect that such a design has a great potential to be applied in the space weather monitoring and solar system planetary exploration drones.

Refined simulation tools for wide field AO systems (such as MOAO, MCAO or LTAO) on ELTs present new challenges. Increasing the number of degrees of freedom (scales as the square of the telescope diameter) makes the standard simulation's codes useless due to the huge number of operations to be performed at each step of the Adaptive Optics (AO) loop process. This computational burden requires new approaches in the computation of the DM voltages from WFS data. The classical matrix inversion and the matrix vector multiplication have to be replaced by a cleverer iterative resolution of the Least Square or Minimum Mean Square Error criterion (based on sparse matrices approaches). Moreover, for this new generation of AO systems, concepts themselves will become more complex: data fusion coming from multiple Laser and Natural Guide Stars (LGS \ NGS) will have to be optimized, mirrors covering all the field of view associated to dedicated mirrors inside the scientific instrument itself will have to be coupled using split or integrated tomography schemes, differential pupil or/and field rotations will have to be considered, etc. All these new entries should be carefully simulated, analysed and quantified in terms of performance before any implementation in AO systems. For those reasons i developed, in collaboration with the ONERA, a full simulation code, based on iterative solution of linear systems with many parameters (use of sparse matrices). On this basis, I introduced new concepts of filtering and data fusion (LGS / NGS) to effectively manage modes such as tip, tilt and defoc in the entire process of tomographic reconstruction. The code will also eventually help to develop and test complex control laws (Multi-DM and multi-field) who have to manage a combination of adaptive telescope and post-focal instrument including dedicated deformable mirrors.\\ The first application of this simulation tool has been studied in the framework of the EAGLE multi-object spectrograph project, one of the main instrument of the future E-ELT, which, in terms of adaptive optics combine all of these issues., La simulation fine de systèmes d'OA a grand champ de type MOAO, MCAO ou LTAO pour l'ELT se heurte a deux problématiques: L'augmentation du nombre de degrés de liberté du système (au carre du diamètre du télescope). Cette augmentation rend les codes de simulation classiques peu (ou pas) utilisables, en particulier en ce qui concerne les processus d'inversion et de calcul matriciel. Il faut donc envisager des approches d'inversion itératives d'un modèle direct y = A * x en s'appuyant sur les théories d'optimisation a base de matrices creuses. La complexite des systèmes, combinant des étoiles naturelles et laser, de grands miroirs déformables couvrant tous le champs et des miroirs dédiés dans les instruments eux memes, des rotations différentielles de pupille et ou de champs. Cette complexité conduit aux développements de procédures nouvelles d'étalonnages, de filtrages et fusion de données, de commandes distribuée ou globale. Ces procédures doivent être simulées finement, comparées et quantifiées en termes de performances, avant d'être implantées dans de futurs systèmes. Pour répondre a ces deux besoins. J'ai développé en, collaboration avec l'ONERA, un code de simulation complet base sur une approche de résolution itérative de systèmes linéaires a grand nombre de paramètres (utilisation de matrices creuses). Sur cette base, j'ai introduit de nouveaux concepts de filtrage et de fusion de données (étoiles laser et étoiles naturelles) pour gérer efficacement les modes de tip/tilt/defoc dans le processus complet de reconstruction tomographique. Ce code permettra aussi, a terme, de développer et tester des lois de commandes complexes (multi-DM et multi-champs) ayant a gérer la combinaison du télescope adaptatif et d'instrument post-focaux comportant eux aussi des miroirs déformables dédiés. La première application de cet outil s'est faite naturellement dans le cadre du projet de spectrographe multi-objets EAGLE, un des instruments phares du futur E-ELT, qui, du point de vue de l'optique adaptative combinera l'ensemble de ces problématiques.