SAW DEVICE AND COMMUNICATION DEVICE USING SAW DEVICE

摘要

A SAW device comprises input/output interdigital transducer (IDT) electrodes (11, 12) provided on piezoelectric substrates (10), a first reflector electrode (13) following the input IDT electrode (11), and a second reflector electrode (14) preceding the output IDT electrode (12). The device satisfies the following inequality (1) to provide preferable characteristics in a pass band: 2(&thetas; - 5) </= tan<-1)<D / L) </= 2(&thetas; +5) where &thetas;: the inclination (in degree, except zero) of the first or second reflector electrode of the input and output IDT electrodes with respect to a plane perpendicular to the direction in which surface acoustic waves travel. D: the pitch (in micron) of the input and output IDT electrodes in the direction in which surface acoustic waves travel. L: the pitch (in micron) of the first and second reflector electrodes. <IMAGE>