Correction of astigmatism and ellipticity of an astigmatic Gaussian laser beam by symmetrical lenses

摘要

Description of the transformation properties of the beam waist parameters of an astigmatic Gaussian beam by a medium characterized by an ABCD matrix is presented. Transformations by thin and thick lenses are considered in detail. We conclude that both astigmatism and ellipticity of the beam can be corrected but not simultaneously. The corrections can be carried out by both proper selection of lens position and of the lens thickness as well; however, in the latter case limitations hold for possible lens positions.