BEAM SHAPING IN THE FRACTIONAL FOURIER-TRANSFORM DOMAIN

A new design approach for the diffractive phase elements (DPE's) that implement beam shaping in the fractional Fourier transform (FRFT) doma in is presented. The new algorithm can successfully achieve the design of DPE's for beam shaping in both unitary and nonunitary transform sy stems. The unitarity transform condition of the FRFT domain is discuss ed. Modeling designs of the DPE's are carried out for several fraction al orders and different parameters of the beam for converting a Gaussi an profile into a uniform beam. Our approach can realize beam shaping well for a nonunitary transform system in the FRFT domain. (C) 1998 Op tical Society America.