| 摘要 |
An elastic wave filter includes electrode fingers, a first busbar and a second busbar, and inclined electrode portions each having a narrower distance between the electrode fingers from the first busbar toward the second busbar. The elastic wave filter includes a dummy electrode disposed in at least one of the input-side IDT electrode portion and the output-side IDT electrode portion to suppress reflection of a diffracted elastic wave by the busbar and to suppress spurious response at an end portion in a frequency pass-band. The dummy electrode has a width dimension and a pitch that are determined such that none of a period shorter than a shortest period of the electrode fingers and a period longer than a longest period of the electrode fingers is satisfied.
|
