Multiconjugate adaptive optics with plenoptic cameras and the Fourier transform reconstructor

Montilla, I.; Reyes, M.; Femenía, B.; Rodríguez-Ramos, J. M.
Referencia bibliográfica

Adaptive Optics Systems II. Edited by Ellerbroek, Brent L.; Hart, Michael; Hubin, Norbert; Wizinowich, Peter L. Proceedings of the SPIE, Volume 7736, pp. 773641-773641-8 (2010).

Advertised on:
7
2010
Número de autores
4
Número de autores del IAC
3
Número de citas
0
Número de citas referidas
0
Descripción
Multi-Conjugate Adaptive Optics (MCAO) will play a key role in future astronomy. Every Extremely Large Telescope (ELT) is being designed with its MCAO module, and most of their instruments will rely on that kind of correction for their optimum performance. Many technical challenges have to be solved in order to develop MCAO systems. One of them, related to its use on ELT's, is to find fast algorithms to perform the reconstruction at the required speed. For that reason we have been studying the application of the Fourier Transform Reconstructor (FTR) to MCAO. We use the Fourier Slice Theorem in order to reconstruct the atmospheric volume. The process consists on reconstructing "slices" of atmosphere, taking 1D-FFT's of the different projections to build a 2D Fourier space that is inverse-transformed to build the reconstructed slice. The advantage of using the FTR is that this algorithm gives us directly the Fourier Transform of the projections, speeding up the process. To do a good reconstruction it is necessary to know the height at which the laser guide star is focused, and we propose to use a plenoptic camera to get this information, that we use together with the available information relative to the atmosphere we are reconstructing, C2n, to weight the inverse-transforms and obtain a better estimate. The height is obtained in real-time, a very important advantage for the reconstruction. We present the preliminary results of our MCAO simulations and the configuration of the plenoptic camera that could be applied to an ELT