Rochon polarizing prism

Rochon polarizing prism

[rō′shōn ′pō·lə‚rīz·iŋ ‚priz·əm]
(optics)
A device for producing linearly polarized beams of light, consisting of two adjacent quartz wedges, the first of which has its optic axis parallel to the beam, while the second has its optic axis perpendicular to the beam; one of the beams (the ordinary ray) is undeviated, and is therefore not spread into a spectrum.