title: Highly convergent focusing of light based on rotating dipole polarization.
abstract: Focusing properties of transverse circular polarization modes that bring light to a small focal spot are investigated. Two particular illumination polarization distributions are discussed. Rotating electric dipole polarization results in a central lobe diameter 8% smaller than for the circularly polarized aplanatic case at a NA of 0.95 in air and is also smaller than for radial polarization at NAs less than 0.90. Azimuthal polarization with a phase singularity of charge unity results in a small central lobe width that is smaller than that produced by focusing radially polarized light, having a width that is 17% smaller than for circularly polarized illumination at a NA of 0.95.
authors.affiliation: Division of Bioengineering, National University of Singapore, Singapore.
authors.forename: Colin J R
authors.initials: CJ
authors.lastname: Sheppard
authors.forename: Shakil
authors.initials: S
authors.lastname: Rehman