Optimization techniques for electromagnetic deformable mirrors

Abstract

The resolution of ground-based telescopes is limited by the blurring caused by Earth’s turbulent atmosphere. Adaptive Optics (AO) is a technique used to correct atmospheric distortions, restoring images to diffraction-limited resolution. The main element of an AO system is the Deformable Mirror (DM), which compensates the distortions of the incoming wavefronts. There are several technologies available to actuate DMs. TNO has developed a novel DM equipped with electromagnetic actuators. Some of the design parameters of the DM have not yet been studied and are subject of optimization. A modeling approach is presented for studying the design sensitivities of the TNO DM. To increase optical performance, a study of optimal actuator layouts and mechanical parameters is shown. For the figure of merit in the optimization, a Fourier modal basis is used. Instead of the more commonly used Zernike basis from literature. This approach constitutes a blueprint for the design of electromagnetic DMs. Its use may be extended to other AO applications such as lithography or ophthalmology.