High order quarter-wave plates and analysis of the directions of rotation in the circular polarizations

The advent of new research subjects, such as plasmas, optical pumping, and atom cooling, has led to an increased use of quarter-wave plates in order t o produce circularly polarized beams with the correct direction of rotation . The recent commercialized quarter-wave plates work in high orders, which leads to a drastic reduction of their pass band. Moreover, the direction of rotation in circular polarization can be affected. The purpose of the pres ent article is to describe new techniques allowing an accurate determinatio n of the optical properties of the used plates. (C) 2000 American Institute of Physics. [S0034-6748(00)01001-7].