An imaging apparatus includes a light source, a spatial light modulator, a Fourier transform optical system, a photodetector, and a control unit. The control unit sets a first region and a second region on a modulation plane of the spatial light modulator, sequentially sets a plurality of light phase modulation patterns in the first region, sequentially sets a plurality of uniform phase shifts in a region other than the first region when setting each light phase modulation pattern in the first region to acquire a light intensity value, and acquires a phase image of a region of an object corresponding to the first region using a phase shift method.