An imaging apparatus includes a diffraction grating which diffracts electromagnetic waves from an electromagnetic wave source, a shield grating which shields a part of the electromagnetic waves diffracted by the diffraction grating, a detector which detects an intensity distribution of the electromagnetic waves through the shield grating, and an adjusting unit which adjusts the attitude of at least one of the diffraction grating and the shield grating on the basis of the detection result by the detector, wherein the adjusting unit divides the intensity distribution detected by the detector into a plurality of regions and adjusts the attitude of at least one of the diffraction grating and the shield grating on the basis of the intensity distributions of the plurality of regions.