Polarization rotators offer 45deg or 90deg rotation at a number of common laser wavelength, the optical axis in a polarization rotator is perpendicular to the polished face of the optic. The result is that the orientation of in put linearly polarized light is rotated as it propagates through the device.

Polarization Rotator

Due to the rotation activity of natural quartz crystal, it also can be used as polarization rotators so that the plane of input linearly polarized beam will be rotated at special angle which is determined by the thickness of quartz crystal.