Dynamic control of Bessel beams through high-phase diffractive axicons

In this work, we present the realization of a high-phase diffractive axicon. For that purpose, we use a spatial light modulator that exhibits 10 pi phase modulation. We compare the results with standard diffractive axicons that exhibit 2 pi phase modulation. We show that high-phase modulation axicons generate Bessel beams with a shorter range and a smaller radius than standard axicons with the same period. We also find that the higher phase modulation regime provides improved diffraction efficiency since fringing effects are reduced. Therefore, dynamic control of Bessel beams is presented, controlled through the phase modulation dynamic range. (C) 2020 Optical Society of America under the terms of the OSA Open Access Publishing Agreement