ELASTIC WAVE DEVICE

摘要

An elastic wave device includes an IDT provided on a piezoelectric substrate. The IDT includes edge areas in which an elastic wave propagation velocity is slower than an elastic wave propagation velocity in a center area of an electrode finger intersecting region. The edge areas are provided on both sides of the center area in an intersecting width direction. The IDT includes a first section where the propagation velocity in the center area is relatively fast and a second section where the propagation velocity in the center area is relatively slow in the elastic wave propagation direction. In accordance with the propagation velocities in the center areas of the first and second sections, the widths and propagation velocities in the edge areas of the first and second sections excite a piston mode.

主权项

1. An elastic wave device comprising:
a piezoelectric substrate; and at least one IDT located on the piezoelectric substrate; wherein the least one IDT includes a plurality of first electrode fingers and a plurality of second electrode fingers interleaved with the plurality of first electrode fingers; in a portion of the least one IDT where the plurality of first electrode fingers and the plurality of second electrode fingers intersect with each other in an elastic wave propagation direction, edge areas are provided on both sides of a center area in an intersecting width direction in which the first and second electrode fingers extend; in the edge areas, an elastic wave propagation velocity is slower than an elastic wave propagation velocity in the center area; the elastic wave device further includes a first section where the propagation velocity in the center area is relatively fast and a second section where the propagation velocity in the center area is relatively slow in the elastic wave propagation direction; and the elastic wave propagation velocity in the center area of the first section and the elastic wave propagation velocity in the center area of the second section, the elastic wave propagation velocity, a width as a dimension along the intersecting width direction in the edge area of the first section, the elastic wave propagation velocity, and a width as a dimension along the intersecting width direction in the edge area of the second section excite a piston mode in each of the first section and the second section.