4Pi focusing of spatially modulated radially polarized vortex beams
4Pi focusing of spatially modulated radially polarized vortex beams is a scholarly work, published in 2012 in ''Optics Letters''. The main subjects of the publication include optics, beam, physics, topological quantum number, light beam, microfluidics, vortex, laser, optical tweezers, trapping, and optical vortex. The authors propose a method for generating focal beams with special intensity distributions using radially polarized vortex beams in a 4Pi configuration.