High-efficiency generation of Bessel-Gaussian vortex beams using Bessel-phase-embedded fork-shaped holograms

In this paper, we present a high-efficiency protocol for constructing pure amplitude and phase Bessel-phase-embedded fork-shaped holograms to generate Bessel-Gaussian vortex (BGV) beams. When illuminated with a Gaussian beam, these holograms produce BGV beams in the first diffraction orders. To quantify the performance of the generated beams, we introduce a quality factor that measures the degree of similarity between the generated BGV beam and an ideal BGV beam. Our results demonstrate that the proposed holograms achieve a significantly higher level of similarity compared to the conventional method of generating BGV beams, which involves the sequential use of a spiral phase plate (SPP) and an axicon or their equivalent computer-generated holograms. Additionally, we compare the diffraction efficiency of BGV beams generated using our approach for both pure amplitude and phase holograms. Phase holograms are implemented using a spatial light modulator (SLM), whereas pure amplitude holograms are printed on sheet glass or plastic substrates. The use of pure amplitude holograms offers a highly efficient, cost-effective, and straightforward method for generating BGV beams, making them an attractive alternative to traditional techniques.