OPTICAL WAVELENGTH FILTER WITH REDUCED SIDELOBES AND SIMPLE DESIGN

摘要

An optical wavelength filter has a polarizer, an analyzer, and an optical waveguide, formed in a substrate displaying an acousto-optic effect, that guides light from the polarizes to the analyzer. A transducer formed on the substrate excites a surface acoustic wave, thus creating an acoustic beam. The amplitude of the surface acoustic wave is small at the two sides of the acoustic beam and larger in the middle. The optical waveguide enters the acoustic beam at a point on one of the two sides of the beam, then moves into the center of the beam, and exits the beam at another point on one of the two sides.