ELASTIC WAVE RESONATOR, LADDER-TYPE FILTER, AND DUPLEXER

摘要

Provided is an elastic wave resonator which is superior in a return loss characteristic at the resonant/antiresonant frequency, and which is capable of effectively decreasing a loss. The elastic wave resonator comprises an IDT electrode (7) wherein a plurality of first electrode fingers (14) and a plurality of second dummy electrode fingers (17) are connected to a first common electrode (12), a plurality of second electrode fingers (15) and a plurality of first dummy electrode fingers (16) are connected to a second common electrode (13), a cross width is weighted in the elastic wave propagation direction, and the metallization ratio at the non-crossing area in the elastic wave propagation direction is high relative to the metallization ratio at the crossing area.