Investigating the Modal Dependencies of Beam Quality - Via Spectrally-resolved Imaging of the Mode Structure in Diode Lasers

Stephen M. Misak, James A. Beil, Rebecca B. Swertfeger, Paul O. Leisher

2017

Abstract

Laser beam quality is an important factor for free-space communication and other high power applications. To achieve the power requirements for such applications, there is a trade-off with the M2 Beam Quality factor. While direct diode lasers offer higher efficiency in a smaller footprint compared to solid-state and fiber laser systems, beam quality is poor due to multi-mode operation. M2 measurements compliant with ISO 11146 standards require numerous measurements, especially for multimode lasers. It is possible to use faster, modal decomposition methods for measuring M2 by employing a spectrometer to spatially separate the modes of a laser. This work presents a custom Echelle Grating Spectrometer for spatially separating laser modes. This tool provides the basis for an alternative method of M2 measurements via Modal Power Distribution analysis.

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Paper Citation


in Harvard Style

Misak S., Beil J., Swertfeger R. and Leisher P. (2017). Investigating the Modal Dependencies of Beam Quality - Via Spectrally-resolved Imaging of the Mode Structure in Diode Lasers . In Proceedings of the 5th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS, ISBN 978-989-758-223-3, pages 245-251. DOI: 10.5220/0006152702450251


in Bibtex Style

@conference{photoptics17,
author={Stephen M. Misak and James A. Beil and Rebecca B. Swertfeger and Paul O. Leisher},
title={Investigating the Modal Dependencies of Beam Quality - Via Spectrally-resolved Imaging of the Mode Structure in Diode Lasers},
booktitle={Proceedings of the 5th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,},
year={2017},
pages={245-251},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0006152702450251},
isbn={978-989-758-223-3},
}


in EndNote Style

TY - CONF
JO - Proceedings of the 5th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,
TI - Investigating the Modal Dependencies of Beam Quality - Via Spectrally-resolved Imaging of the Mode Structure in Diode Lasers
SN - 978-989-758-223-3
AU - Misak S.
AU - Beil J.
AU - Swertfeger R.
AU - Leisher P.
PY - 2017
SP - 245
EP - 251
DO - 10.5220/0006152702450251