Acousto-optical light refraction system - has lithium sulphate input layer on gold electrode a carrier layer and salt resonator

摘要

The acousto-optical refraction system comprises a sound converter (1) made of lithium sulphate monohydrate in flat plate form, which surmounts a gold film electrode (2). The latter is mounted on a wedge shaped intermediate carrier (3) which may be of quartz or aluminium. The next layer is a resonant medium (4), typical of alpha iodine salt, and this is mounted on a base layer (5) of sound absorbing glass. The sound input produces ultrasonic vibrations (6) in the intermediate carrier (3). The vibrations transmitted to the salt layer (4) cause an incident light beam (7) to be refracted, the emergent beam (8) having an angle determined by Bragg's Law with a phase displacement as appropriate.