An intraoral sensor includes an image sensor, an FOP, a scintillator, and a case. The FOP includes a first main surface, a second main surface, and a plurality of lateral surfaces. The first main surface and the second main surface have a polygonal shape. An edge of the second main surface is constituted by a plurality of corner portions, and a plurality of side portions connect the corner portions adjacent to each other. The scintillator is provided on the second main surface and the plurality of lateral surfaces in such a manner that the corner portions and the ridge portions constituted by the lateral surfaces adjacent to each other are exposed.
