A Fabri-Perot filter includes: a substrate; a first mirror disposed on the substrate; and a movable mirror unit facing the first mirror with a gap therebetween. The movable mirror unit is movable toward the first mirror in a case where a predetermined voltage is applied between the first mirror and the movable mirror unit so that the gap is changeable. The filter is capable of transmitting an infrared light having a predetermined wavelength corresponding to the gap. The movable mirror unit includes a center portion and a periphery portion, which is deformable easier than the center portion.