Acousto-optic and electro-optic modulators for stereoscopic laser videoprojection

An original combination of acousto-optic modulators and electro-optic cells for stereoscopic laser videoprojection is presented. It is based on the separation by orthogonal polarizations of the two left and right images of a stereoscopic pair. As several video lines are scanned simultaneously, the acousto-optic modulators operate in multifrequency mode. The polarization states are controlled by the electro-optical devices. A practical bifrequency acousto-optic modulator using the slow shear acoustic wave in paratellurite has been designed, and an electro-optic device with four ammonium dihydrogen phosphate crystals has been implemented. Experimental results are reported.