Twist of coherent fields and beam quality

An optical system is presented which transforms an arbitrary astigmatic beam into one of circular symmetry with twist. This holds for coherent and partially coherent fields. Experiments were performed with Gauss-Hermitian modes TEMno, transforming them into ring-like structures of Gauss- Laguerre type modes. The theoretical results concerning intensity structure and beam propagation factor were confirmed.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.