A principal scheme for an external cavity technique for changing the polarization of a laser beam based on a modified Sagnac interferometer is proposed. The modified Sagnac interferometer includes standard optical components: a displacement polarizing beam splitter, an angle reflector, and a Dove prism. The radially polarized beams, obtained with the help of the developed scheme, allow the generation of a longitudinally polarized electric field by sharp focusing. The phase correction of radially polarized modes of higher orders leads to increasing the longitudinal field in the focus of the beam.
© 2006 Optical Society of America
Original Manuscript: March 29, 2006
Revised Manuscript: June 20, 2006
Manuscript Accepted: July 2, 2006
V. G. Niziev, R. S. Chang, and A. V. Nesterov, "Generation of inhomogeneously polarized laser beams by use of a Sagnac interferometer," Appl. Opt. 45, 8393-8399 (2006)