Murugesan RThiruArul DRajesh K BLavanya MMahadevan G2020-09-282020-09-282010-10-242361-5092https://www.vibgyorpublishers.org/content/ijoe/fulltext.php?=ijope-3-011https://dspace.psgrkcw.com/handle/123456789/1823Focusing properties of circularly polarized annular multi-Gaussian beams through a uniaxial birefringent crystal is investigated numerically by vectorial Debye theory. Results show that the optical intensity in focal region of circularly polarized annular multi-Gaussian beams can be altered considerably by the topological charge [n], beam order [m] and birefringence [Δn]. Many novel focal structures such as focal spot, focal hole and flat top profile of sub wavelength structure are achieved.enArticle