Computing the Influence Functions of an Adaptive Optics Large Deformable Mirror: the Numerical Method and the Experimental Data

R. Biasi[1], D. Gallieni[2], A. Riccardi[3], R. Briguglio[3], C. Del Vecchio[3]
[1]Microgate Srl, Bolzano, Italy
[2]ADS International Srl, Valmadrera (LC), Italy
[3]National Institute for Astrophysics - Arcetri Astrophysical Observatory - Firenze, Italy
发布日期 2013

Adaptive Optics units are mounted on many large telescopes, thus enabling diffraction-limited astronomical images through compensation of the effects of atmospheric turbulence. The design of the control system of the Deformable Mirror includes a feed-forward block, aimed for increasing the efficiency of the control loop. Such a block is based on the stiffness matrix of the DM, defined as the force required to move a single actuator while all the others are constrained at zero positions. The mirror shape caused by this force pattern is called Influence Function. This paper discusses the computation methods adopted to calculate the IFs of the LBT and VLT DMs, grounded in the capabilities of the COMSOL Multiphysics® / MATLAB® interactions. The experimental data match the COMSOL Multiphysics® results.