Visualization 1.avi RasouliSaifollah HebriDavud 2018 Calculated diffraction patterns from an amplitude radial grating with m=10 illuminated by the vortex beams with w=2mm and l= 3, 10 at different propagation distances in the range from z=0 to z=10z_T. For the cases l= m= 10 by propagation, beams' energy are flowing towards the optical axes. All dimensions are in millimeters.