Patent ID: 8390400

Claim:
An acoustic wave element comprising: a piezoelectric material; and at least one IDT electrode contacting the piezoelectric material and including a plurality of electrode fingers including first and second electrode fingers that are adjacent to each other in an acoustic wave propagation direction and that connect to different potentials and a first dummy electrode finger that faces the first electrode finger via a gap located on an outer side in an electrode finger length direction of an end of the first electrode finger and that connects to the same potential as the potential connected to the second electrode finger; wherein in an area of an IDT electrode crossing region in which the first and second electrode fingers that are adjacent to each other overlap each other in the acoustic wave propagation direction near the gap, a first protrusion is provided in at least one of the first electrode finger and the first dummy electrode finger, the first protrusion protruding in the acoustic wave propagation direction from at least one of side edges of the at least one of the first electrode finger and the first dummy electrode finger so as to define a protrusion portion of the at least one of the first electrode finger and the first dummy electrode finger that has a width in the acoustic wave propagation direction that is greater than a width of the first electrode finger; and the first protrusion is in contact with the gap.