Beam shaping and splitting for high-power USP-lasers

Abstract

A spatial light modulator is used to flexibly shape and divide a femtosecond laser beam. The phase masks required for this task are generated by iterative algorithms like the well-known Gerchberg-Saxton-Algorithm (GSA). However, the GSA tends to generate phase masks containing singularities, leading to severe deviations from the desired target intensity distribution. To address this, a modified GSA was developed which avoids singularities and is capable of finding phase solutions being close to analytic ones in cases where they exist. Measurements of the corresponding intensity distributions are shown. The aim of this development is to parallelize micromachining with high-power USP-lasers.