Acoustooptic 2×2 switch for radiation with different wavelengths as an element of a fiber-optic gyroscope

Planar acoustooptic 2×2 directional couplers that switch optical rays with different wavelengths are considered. A method for calculating the angular and frequency characteristics of such switches is developed, and the parameters of a switch based on a planar Ti-LiNbO₃ structure are calculated. Experiments employing bulk acoustooptic diffraction in TeO₂ are performed, confirming the basic theoretical assumptions. It is shown experimentally that the best conditions for switching optical rays directed into optical fibers can be provided nearly always by varying the diffraction angles and the frequencies of the sound waves. The functional possibilities of the 2×2 directional coupler investigated in a fiber-optic gyroscope are described. Zh. Tekh. Fiz. 67, 57–62 (July 1997)