Beam quality characterization of a radial laser array

Abstract

With the Hermite-Gaussian mode used to describe radial laser arrays and the M²-factor and power in the bucket (PIB) chosen as criteria for characterizing beam quality, a detailed study of beam quality of coherent and incoherent radial laser arrays is made. The closed-form expression for the M²-factor of incoherent radial arrays, which depends upon the Hermite-Gaussian order m, inverse radial fill factor r' and aspect ratio w _0x /w _0y , is derived. Numerical examples are given to illustrate and compare beam quality of coherent and incoherent radial arrays.