Generation of complex optical fields by double phase modulation in a SLM

Abstract

We employ a setup, based on a phase spatial light modulator (SLM), for generation of arbitrary optical fields. The process is based on two sequential phase modulations of a laser beam at two different zones of the SLM. The input beam is transformed in the first contact with the SLM by a phase modulation that includes a diffractive phase element (DPE), which encodes the desired complex field, and a Fourier transforming lens. The Fourier transform of the DPE is projected, using a mirror, to the second SLM modulation area, whose transmittance includes a second Fourier transforming lens and a phase spatial filter, used to eliminate non-desired parts of the DPE Fourier spectrum.