Patent ID: 7456710

Claim:
A surface acoustic wave (SAW) resonator, comprising: a first interdigital transducer composed of a pair of interdigital electrodes provided in a propagation direction of a surface acoustic wave; a second interdigital transducer composed of a pair of interdigital electrodes provided in parallel to the first interdigital transducer; and a switch that alternately switches the pair of interdigital electrodes of the first interdigital transducer and the pair of interdigital electrodes of the second interdigital transducer; wherein 7λ≦B≦33λ where λ is a wavelength of a surface acoustic wave, and B is an addition of a width a 1 of an engaged section of electrode fingers of the first interdigital transducer, a width a 2 of an engaged section of electrode fingers of the second interdigital transducer and a distance b between the engaged sections of both interdigital transducers.