Unidirectional surface acoustic wave device with meandering electrode

摘要

A surface acoustic wave device on a piezoelectric substrate comprises an interdigital transducer having an interdigital sending part in the forward direction and an interdigital reflecting part in the reverse direction. An electrical phase difference of phi (radian) is applied between the sending and reflecting parts, while the distance between the sending and reflecting parts providing a geometrical phase difference therebetween is established to be <IMAGE> where n is a positive integer and lambda o is the wavelength of surface acoustic wave. A third, common electrode meanders between the sending and reflecting electrodes.