Acoustic wave device

An acoustic wave device comprising:

• a piezoelectric layer including lithium niobate;
• a first comb-shaped electrode on the piezoelectric layer, including a first busbar and a plurality of first electrode fingers each including one end connected to the first busbar, and being connected to an input potential;
• a second comb-shaped electrode on the piezoelectric layer, including a second busbar and a plurality of second electrode fingers each including one end connected to the second busbar and interdigitated with the plurality of first electrode fingers, and being connected to an output potential;
• and
• a reference potential electrode including a plurality of third electrode fingers on the piezoelectric layer and aligned with the first electrode fingers and the second electrode fingers in a direction in which the first electrode fingers and the second electrode fingers are aligned, and a connection electrode connecting adjacent third electrode fingers, the reference potential electrode being connected to a reference potential;
• wherein
• a first electrode finger, a second electrode finger, and a third electrode finger are arranged such that, starting from the first electrode finger, the first electrode finger, the third electrode finger, the second electrode finger, and the third electrode finger define one period;
• and
• the acoustic wave device further includes:
• a pair of reflectors, each including at least one reflector electrode finger, on the piezoelectric layer sandwiching a region where the first electrode finger, the second electrode finger, and the third electrode finger are provided in an electrode finger orthogonal direction orthogonal or substantially orthogonal to a direction in which the first electrode finger, the second electrode finger, and the third electrode finger extend.