SURFACE ACOUSTIC WAVE APPARATUS AND COMMUNICATION APPARATUS

摘要

A surface acoustic wave apparatus wherein the infinitesimal ripples in a passband can be prevented from occurring, the insertion loss has been improved and the balancing degree has been improved. Each of first and second surface acoustic wave elements (14,15) parallel connected to a surface acoustic wave resonator (16) has an odd number, which is equal to or greater than three, of IDTs (2-4,5-7) having a plurality of electrode fingers arranged in the propagation direction of surface acoustic waves propagating over the piezo-electric board (1) and further has reflectors (8,20,21,10) located at the both ends of the IDT sequence and having a plurality of electrode fingers. Moreover, all of the electrode fingers of the IDTs and reflectors are arranged in such a manner that the polarities of the electrode fingers each located adjacent to a different IDT or reflector are symmetric with respect to the central IDT.