Twisted Gaussian Schell-model beams: interpretation and experiments

In (synthetic) holography and diffractive optics, the optical field is often decomposed in a set of spherical waves, which are usually approximated paraxially. On the other hand, however, it is known that gaussian beams are exact solutions of the paraxial wave equation. Moreover they have the remarkable property that their Fourier transform is also a Gaussian beam. This makes them very interesting as basis functions for calculations in Fourier optics. In other words : the field is written as a sum (or integral) of gaussian beams, instead of a sum (integral) of plane or spherical waves. Up to now however, the use of Gaussian beams has been limited to laser optics ; we advocate their use in Fourier optics.