Adjustable Wollaston-like prisms

Abstract

A combination of a polarizing beam splitter and two quarter wave plates is used to direct a beam of light into one of two directions, depending on its polarization. Its function is similar to that of a Wollaston prism, except that the angle between the two directions is adjustable and does not vary with wavelength. Three cascaded units have been used to deflect a beam of light into eight selectable directions.