Acousto-optic tunable filter with two acoustic channels.

摘要

The invention provides an acousto-optic tunable filter configuration. The configuration, a non-collinear acousto-optic tunable filter crystal has a first transducer bonded to one transducer face of the crystal and a single transducer bonded on the opposite crystal face which crystal face is cut so as to be parallel to the first transducer. The first transducer operates at a center frequency f1 and the second transducer operates at a center frequency f2. Extending the tuning range of the filter comprises introducing incident light into the filter which filter comprises a crystal having an optical input face, an optical output face and first and second parallel sides. Launching acoustic waves having a center frequency f1 into the crystal from the crystal's first side. Acoustic waves having a center frequency f2 are launched into the crystal from the crystal's second side.