A wafer includes a substrate layer, a first mirror layer having a plurality of two-dimensionally arranged first mirror portions, and a second mirror layer having a plurality of two-dimensionally arranged second mirror portions. A plurality of Fabry-Perot interference filter portions are formed in an effective area, in each of the plurality of Fabry-Perot interference filter portions a gap is formed between the first mirror portion and the second mirror portion. A plurality of dummy filter portions are formed in a dummy area disposed along an outer edge of the substrate layer and surrounding the effective area, in each of the plurality of dummy filter portions an intermediate layer is provided between the first mirror portion and the second mirror portion. At least the second mirror portion is surrounded by the first groove in each of the plurality of Fabry-Perot interference filter portions and the plurality of dummy filter portions.