4. Experimental setup

Measurement of the phase and amplitude of the diffracted optical field is traditionally based on an interferometric set-up combined with a system for angular scanning of the illumination and/or rotation. Figure 15 shows a Mach-Zehnder interferometer. A laser source is split by a fibered splitter into an illumination wave and a reference wave. These two waves are injected into single-mode optical fibers to adjust the optical path difference.