We examine the effects of tightly focusing a radially polarized beam with uniform, Gaussian, or Bessel–Gauss pupil functions. The resulting FWHM is smallest for the case of a uniform amplitude profile, while the Bessel–Gauss beam results in the largest FWHM. The uniform amplitude profile also results in an axial field component that increases fastest with increasing NA. The ratio of the axial component to the transverse component is also the greatest for the uniform pupil function. On the other hand, the Bessel–Gauss beam benefits the most from the use of an annulus.
© 2007 Optical Society of America
Original Manuscript: August 14, 2007
Revised Manuscript: October 11, 2007
Manuscript Accepted: October 30, 2007
Published: November 21, 2007
Vol. 3, Iss. 1 Virtual Journal for Biomedical Optics
Elijah Y. S. Yew and Colin J. R. Sheppard, "Tight focusing of radially polarized Gaussian and Bessel-Gauss beams," Opt. Lett. 32, 3417-3419 (2007)