title: Focal shift in focused radially polarized ultrashort pulsed laser beams.
abstract: Beginning with a beam coherence polarization (BCP) matrix, we obtain an analytical intensity expression for radially polarized ultrashort pulsed laser beams that pass through an apertureless aplanatic lens. We also investigate the intensity distribution of radially polarized beams in the vicinity of the focus. The focal shift of these beams is studied in detail. The focal shift depends strongly on Z(F) that coincides with pi times the Fresnel number.
authors.affiliation: Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China. wuguohua78@yahoo.com.cn
authors.forename: Guohua
authors.initials: G
authors.lastname: Wu
authors.forename: Qihong
authors.initials: Q
authors.lastname: Lou
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.forename: Jingxing
authors.initials: J
authors.lastname: Dong
authors.forename: Yungrong
authors.initials: Y
authors.lastname: Wei