We explain a technique that extracts both the structure and the modal weights of spatial modes of lasers by analyzing the spatial coherence of the beam. This is the first time, to our knowledge, that an experimental method is being used to measure arbitrary forms of the spatial modes. We applied this method to an edge-emitting Fabry–Perot semiconductor laser with a stripe width of 5 μm and extracted fundamental and first-order lateral modes with relative power weights of 96.2% and 3.8%. There was a single transverse mode.
© 2000 Optical Society of America
(030.1640) Coherence and statistical optics : Coherence
(030.4070) Coherence and statistical optics : Modes
(120.3180) Instrumentation, measurement, and metrology : Interferometry
(140.5960) Lasers and laser optics : Semiconductor lasers
Carolyn M. Warnky, Betty Lise Anderson, and Charles A. Klein, "Determining Spatial Modes of Lasers with Spatial Coherence Measurements," Appl. Opt. 39, 6109-6117 (2000)