Research of optical vortex’s energy efficiency and diffraction angle based on spatial light modulator

We systematically study the effects of computer-generated hologram characteristics and spatial light modulator (SLM) performance on the quality of the optical vortex (OV). To improve the energy efficiency of the OV, the blazed fork gratings are introduced to transfer most of the energy to +1 diffraction order of SLM, and the relationship among three kinds of holograms is discussed. A mathematical model, based on the digital blazed grating theory, is proposed to analyze the diffraction angle and energy efficiency of +1 order. The theoretical analysis is further validated by experimental results. The research provides useful guidelines for OV-related applications.