Surface acoustic wave transducer

Abstract

A unidirectional surface acoustic wave (SAW) transducer has a substrate which is piezoelectric or electrostrictive, a first IDT (interdigital transducer) electrode disposed on a surface of the substrate and having a plurality of first electrode fingers, and a second IDT electrode disposed on the surface of the substrate and having a plurality of second electrode fingers alternating with the first electrode fingers, and structural elements disposed on the surface of the substrate and arranged periodically in a propagating direction of surface acoustic waves. The structural elements comprise grooves or dielectric films each having a width of λ0/4 or λ0/2, for example, where λ0 represents a wavelength corresponding to a fundamental operating frequency of the unidirectional surface acoustic wave transducer.

Dependencies are inferred from the claim text.