The Raspberry Pi auto-aligner: Machine learning for automated alignment of laser beams

Rev Sci Instrum. 2021 Jan 1;92(1):015117. doi: 10.1063/5.0032588.

Abstract

We present a novel solution to automated beam alignment optimization. This device is based on a Raspberry Pi computer, stepper motors, commercial optomechanics and electronic devices, and the open-source machine learning algorithm M-LOOP. We provide schematic drawings for the custom hardware necessary to operate the device and discuss diagnostic techniques to determine the performance. The beam auto-aligning device has been used to improve the alignment of a laser beam into a single-mode optical fiber from manually optimized fiber alignment, with an iteration time of typically 20 minutes. We present example data of one such measurement to illustrate device performance.