Acoustic wave device and composite filter device

An acoustic wave device comprising:

• a piezoelectric substrate;
• an interdigital transducer (IDT) electrode on or above the piezoelectric substrate;
• and
• a pair of reflectors on both sides of the IDT electrode in a first direction on the piezoelectric substrate, the first direction being a propagation direction of an acoustic wave;
• wherein
• each of the pair of reflectors includes a plurality of electrode fingers extending in a second direction, the second direction being perpendicular or substantially perpendicular to the first direction;
• each of the plurality of electrode fingers includes a first end portion located at one end in the second direction and a second end portion located at the other end in the second direction;
• an electrode finger width of the second end portion of each of the plurality of electrode fingers is greater than the electrode finger width of the first end portion, the electrode finger width being a dimension of each of the plurality of the electrode fingers in the first direction;
• and
• the electrode finger width at any given position in each of the plurality of electrode fingers is equal to or greater than the electrode finger width at a position closer than the given position to the first end portion.