Abstract

Cylindrical vector beams possess an inhomogeneous linear polarization, which has cylindrical symmetry about the optical axis. Two members of this family exist: the azimuthally-polarized beam possesses an electric field which is always transverse, even under high numerical aperture focusing. The radially-polarized beam exhibits, in the focal region, a strong longitudinal component to the electric field. We have employed these beams in surface and particle metrology, with attention to micro-polarimetry of particles, imaging of surface gradients, and single-molecule microscopy. Of particular interest is the use of longitudinal field imaging for the characterization of surfaces; fundamental questions are raised about what, exactly, is being probed on the surface in question. We present the results of recent experiments and discuss the prospects for using linear and nonlinear optical techniques for surface and particle metrology.

© 2002 Optical Society of America