Tight Focusing Properties of Azimuthally Polarized Lorentz Gaussian Beam

The tight focusing properties of azimuthally polarized Lorentz Gauss beam is investigated theoretically by Vector Diffraction Theory. It is observed from the results that Non-Vortex Lorentz Gauss beam generated a sub wavelength focal hole under the tight focusing condition. It is also noted that FWHM of the focal hole andits focal depth suffers little change with the change in Lorential parameter. However when annular obstruction is introduced, the focal hole seems to get confined and improvement in the focal depth is observed. Focusing of Lorentz Gauss beam one optical vortex shows the formation of focal spot of sub wavelength size. It is also noted introduction of annular obstruction improved focal depth and reduced the spot size of the generated focal spot for the Lorential parameters considered.