Multi-helix beams generated with binary helico-conical phase patterns

In this paper, we generate a type of double helico-conical beam (HCB) by binarizing the modified helico-conical phase (MHCP). The diffraction patterns of the double HCBs were analyzed theoretically and experimentally. The relative position of the double HCBs can be adjusted arbitrarily by introducing a blazed grating only. In addition, the superposition of multiple binary MHCPs can be used to generate multi-helix beams. Accordingly, the diffraction patterns of the multi-helix beams were also analyzed theoretically and experimentally. The results demonstrated that the number and relative position of multi-helix beams can be adjusted by the number of superimposed MHCP profiles and the azimuth factor θj, respectively. This kind of arrayed HCB will be potentially applied in the fields of optical manipulation and multiplexed holography.