Surface acoustic wave device for portable telephone system, has interdigital transducer with electrode fingers comprising specified gap portion whose polarization direction is different from others

摘要

The acoustic wave device has an interdigital transducer comprising multiple electrode fingers provided on a piezoelectric substrate (10) made of lithium tantalum trioxide (LiTaO3). The polarization direction in a gap portion between the electrode fingers of the transducer is different from polarization direction in other gap portions between electrode fingers on the same propagation path. Independent claims are also included for the following: (a) Duplexer; (b) Communication device; (c) Surface acoustic wave device manufacturing method