Sharp focusing of radially polarized light with microlenses

Based upon the radial FDTD-method developed, we show numerically that super-resolution can be achieved by focusing a radially polarized laser beam with a cylindrical gradient Michaelian microlens and a conical microaxicon. The (FWHM) focal spot areas in these cases are 0.152λ and 0.096λ, respectively. These values are less than those experimentally obtained to date with the use of a microobjective (0.160λ2), a parabolic mirror (0.134λ2), a minimal theoretical estimate (0.101λ2), and definitely less than the diffraction limit (Airy disk area) of 0.204λ2.