Implementation of a Phase Only Spatial Light Modulator as an Atmospheric Turbulence Simulator at 1550 nm

Abstract

Modeling and simulating atmospheric turbulence in a controlled environment have been a focus of interest for scientists for decades. The development of new technologies allows scientists to perform this task in a more realistic and controlled environment and provides powerful tools for the study and better understanding of the propagation of light through a nonstatic medium such as the atmosphere. Free space laser communications (FSLC) and studies in light propagation through the atmosphere are areas which constantly benefit from breakthroughs in technology and in the development of realistic atmospheric turbulence simulators, in particular (Santiago et al. 2011). In this paper, we present the results from the implementation of a phase only spatial light modulator (SLM) as an atmospheric turbulence simulator for light propagation in the short-wave infrared (SWIR) regime. Specifically, we demonstrate its efficacy for its use in an FSLC system, at a wavelength of 1550 nm.

Folded optical design for high fidelity atmospheric emulation with a spatial light modulator

“…Atmospheric emulators made with spatial light modulators (SLMs) offer the ability to test a laser communication component's performance while in the laboratory with a broad range of turbulence levels [1][2][3][4][5][6][7][8][9][10][11][12][13] . When compared to rotating phase plates [14][15][16][17][18] (another common option for emulating atmosphere in the laboratory), SLM based systems have a speed limitation, restricting real time recreation of atmospheric optical turbulence evolving at typical Greenwood frequencies.…”

“…Commonly, SLM-based emulators are designed using a phase screen approach 1,4,6,9,10 . The phase screen approach loses fidelity for lower elevation propagation paths due to the intensity nulls which form in conjunction with branch points in deep turbulence.…”