A mask according to an embodiment comprises: a first substrate; a first wiring arranged on the first substrate; a plurality of piezoelectric elements arranged on the first wiring; a second wiring arranged on the piezoelectric elements; a second substrate arranged on the second wiring; a third wiring arranged on the first substrate and electrically insulated from the first wiring; and a plurality of light-emitting elements arranged between the first and second substrates and arranged on the third wiring, wherein the plurality of light-emitting elements are arranged in areas overlapping, in a vertical direction, areas between the piezoelectric elements.