Experimental implementation of phase triplicator gratings in a spatial light modulator

In this work, we compare different methods for implementing a triplicator, a phase grating that generates three equiintense diffraction orders. The design with optimal efficiency features a continuous phase profile, which cannot be easily reproduced, and is typically affected by quantization. We compare its performance with binary and sinusoidal phase profiles. We also analyze the effect of quantizing the phase levels. Finally, a random approach is adopted to eliminate the additional harmonic orders. In all cases, a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.