Formation of a beam of high optical quality in a multistage neodymium laser

A report is given of an investigation of the formation of the intensity profile of laser radiation by the application of the spatial filtering and apodization method to a high-power neodymium system. Optimal conditions are found for the filtering of spatial frequencies and the newly developed simplest vacuum spatial filter is described. The method for making soft apertures by the evaporation of metal films on glass substrates is reported together with a study of the apodizing properties of these apertures. A study of spatial coherence of apodized laser radiation is described. The results are given of the formation of a beam of high optical quality in a high-power system with an exit aperture 45 mm in diameter.