Experimental evaluation of methods for identifying spatial distributions of laser beam intensity

When developing and certifying laser radiation sources, it is necessary to know the characteristic that determines the similarity of the spatial distributions of the emitted beam intensity to a Gaussian distribution. The well-known numerical measure М ² serves as such a characteristic. However, in practice, to expand our knowledge of laser beam parameters, additional measures are required to assess the similarity of the spatial distribution of its intensity not only to a Gaussian distribution, but also to an arbitrarily specifi ed distribution. The authors previously developed identifi cation methods based on such measures, which make it possible to eliminate the shortcomings of the М ² measure. To confi rm the correctness of the theoretical conclusions, four methods for identifying the spatial distributions of the laser beam intensity of the LS-2131M-10-SHG-MN solid-state pulsed laser source (Belarus) were experimentally evaluated. The spatial distributions of the emitted beam intensity are compared with a Gaussian intensity distribution. Using the proposed additional measures, unlike the М ² measure, it is possible to perform identifi cation in real time. The experiments utilized a prototype of a laser beam intensity spatial distribution measurement instrument developed at the All-Russian Research Institute of Optical and Physical Measurements. It utilized a Contrastech Mars 4100-904100-90 multi-element measuring transducer (China) and a computer with integrated laser beam spatial distribution identifi cation software. Experiments demonstrated that the identifi cation measures are highly sensitive to changes in the spatial distribution of laser beam intensity and can be a useful tool for real-time tuning of laser sources.

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