Authors:
Stephen M. Misak
;
James A. Beil
;
Rebecca B. Swertfeger
and
Paul O. Leisher
Affiliation:
Rose-Hulman Institute of Technology, United States
Keyword(s):
Beam Quality, Tapered Diode Laser, Broad-Area Diode Laser, Echelle Grating Spectrometer, Spectrally-Resolved Modes, Modal Power Distribution, Astigmatism.
Related
Ontology
Subjects/Areas/Topics:
Lasers
;
Optical Instrumentation
;
Optics
;
Photonics, Optics and Laser Technology
;
Semiconductor Lasers and Leds
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.