Rotation of laser beam polarization in acousto-optic devices

When a linear, polarized laser beam is passed through an acousto-optic device, the polarization direction of the outgoing beam is often different from that of the entering beam, and thus a rotation of the polarization angle takes place. This paper shows how the polarization rotation and the intensity can be calculated for different polarization angles. Experimental results obtained with a single crystal germanium frequency shifter in the 10.6 μm region agreed well with theory.