Large angle nonmechanical laser beam steering at 4.6  μm using a digital micromirror device

Abstract

Large angle, nonmechanical beam steering is demonstrated at 4.62 μm using the digital light processing technology. A 42-deg steering range is demonstrated, limited by the field-of-view of the recollimating lens. The measured diffraction efficiency is 8.1% on-axis and falls-off with a sin 2 dependence with the steering angle. However, within the 42-deg steering range, the power varied less than 25%. The profile of the steered laser beam is Gaussian with a divergence of 5.2 mrad. Multibeam, randomly addressable beam steering, is also demonstrated. © The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License. Distribution or reproduction of this work in whole or in part requires full attribution of the original publication, including its DOI.

Aberration and coherence effects with a micromirror array

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