Laser propagation analysis using Plexiglas™ burn samples

A method is developed to determine the propagation characteristics of a high power laser beam using only PlexiglasTM burn patterns. Under the assumption of an embedded Gaussian in the laser beam and using ABCD ray analysis, the fundamental laser beam characteristics, independent of the optical array, are determined. The method can be used to approximate the beam irradiance profile, peak irradiance, and beam characteristic size along the beam path, the cavity induced curvature applied to the beam, and the laser beam Rayleigh range. Finally, the beam far-field spreading angle and beam quality relative to an ideal beam are calculated. The method developed defines gross characteristics of aberrated beams generated by both stable and unstable laser designs.