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arXiv · 1409.3675

Microcontroller-based locking in optics experiments

K. Huang·H. Le Jeannic·J. Ruaudel·O. Morin·J. Laurat
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Abstract

Optics experiments critically require the stable and accurate locking of relative phases between light beams or the stabilization of Fabry-Perot cavity lengths. Here, we present a simple and inexpensive technique based on a stand-alone microcontroller unit to perform such tasks. Easily programmed in C language, this reconfigurable digital locking system also enables automatic relocking and sequential functioning. Different algorithms are detailed and applied to fringe locking and to low- and high-finesse optical cavity stabilization, without the need of external modulations or error signals. This technique can readily replace a number of analog locking systems advantageously in a variety of optical experiments.

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K. Huang, H. Le Jeannic, J. Ruaudel, O. Morin, J. Laurat. 2015-01-09. Microcontroller-based locking in optics experiments. https://doi.org/10.1063/1.4903869

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