Symmetrical iterative Fourier-transform algorithm using both phase and amplitude freedom for the design of diffractive beam shaping elements

In this paper, we present a symmetrical iterative Fourier transform algorithm (IFTA) using both the phase and amplitude freedom (SIFTA_(p+a)) for the design of diffractive beam shaping elements. This algorithm is compared to the GSA, IFTA_(p+a), and SIFTA_(p), which is symmetrical IFTA exclusively using phase freedom. We compare these four methods by employing them to a number of flat-top super-Gaussian (SG) beam shaping problems. In this paper the modified Fourier-domain constraint is decided automatically by iteration