ANGLE FREQUENCY RELATIONSHIP FOR A PRACTICAL ACOUSTOOPTIC DEFLECTOR

A number of designs have been proposed for acousto-optic deflectors that use anisotropic acousto-optic diffraction in TeO2. The interaction geometries commonly used permit acceptable deflection angles by ensuring that, to first order, the required angle of incidence of the optical beam is fixed. For these interaction geometries, a complicated relationship between the deflection angle and the acoustic frequency is predicted. However, a simple linear relationship is observed experimentally. It is shown that this discrepancy is due to the angular spread in the acoustic beam, which is necessary for the operation of a practical acousto-optic deflector.