Focal Pattern of Hyperbolic-Cosine-Gaussian Beam with Optical Vortex

Intensity distribution in focal region plays an important role in many optical systems, including optical tweezers, imaging system, and analysis instrument. The focal pattern of the hyperbolic-cosine-Gaussian beam with vortex was investigated theoretically in this article. The vortex includes one non-spiral vortex created by linear phase plate, and one spiral vortex created by spiral phase plate. By adjusting the parameters of the vortex, focal pattern evolves considerably, and some novel focal patterns may come into being, such as focal ring, two-peak pattern, four-peak pattern, which may be used to construct optical traps.