Different applications such as astronomy, remote optical sensing and free space optical communications, among others, require both numerical and laboratory experimental simulations of beam propagation through turbulent atmosphere prior to an outdoor test. While rotating phase plates or hot chambers can be applied to such studies, they do not allow changing the atmospheric conditions and the propagation distance in situ. In contrast, the spatial light modulators (SLMs) are a flexible alternative for experimental turbulence simulation. In this work we consider an experimental setup comprising two SLMs for studying laser beam propagation in weak atmospheric turbulence. The changes of atmospheric conditions and propagation distances are properly achieved by the adjustment of the phase screens and the focal distances of digital lenses implemented in both SLMs. The proposed system can be completely automatized and all its elements are in fixed positions avoiding mechanical misalignment. Its design, propagation distance and atmospheric condition adjustment are provided. The setup performance is verified by numerical simulation of Gaussian beam propagation in the weak turbulence regime. The obtained parameters: scintillation index, beam wander and spreading are compared to their theoretical counterparts for different propagation distances and atmospheric conditions.
In this paper a new class of optical vortex known as <i>perfect</i> vortex and its generation by means of a liquid crystal spatial light modulator (LC-SLM) is reported. Unlike other techniques, optical vortices with true controllable dark core radius and any topological charge are obtained. Experimental results using LC-SLM model LC2002 Holoeye are shown.
An experimental technique for controlling the statistical properties of a primary source by means of nematic 90°-twist
liquid-crystal spatial light modulators (LC-SLMs) is proposed. The modulation of coherence and polarization is achieved
through computer generated random signals applied to LC-SLMs placed at the opposite arms of an interferometric setup.
Experimental results obtained by using Holoeye LC2002 modulators show the efficiency of the proposed technique.