An image capturing device in one aspect of the present invention includes: an imaging device; a lens optical system including a focus lens; a driving section for driving one of the imaging device and the focus lens; a displacement control section for controlling displacement of the imaging device or the focus lens to be driven based on a predetermined displacement pattern; a diaphragm having an aperture having a size which can be changed and being provided in the lens optical system; an aperture control section for controlling the size of the aperture of the diaphragm; a synchronizing section for controlling the displacement control section and the aperture control section based on exposure timing; and an image capturing parameter determining section for determining the exposure time, the size of the diaphragm aperture, and the displacement pattern, wherein: the predetermined displacement pattern includes a first-type displacement pattern and a second-type displacement pattern by which the imaging device or the focus lens is displaced over different ranges between a first focus position and a second focus position in an image capturing scene; the first-type displacement pattern and the second-type displacement pattern are repeated alternately; and the aperture control section controls the diaphragm so as to have a first aperture and a second aperture having a different size from that of the first aperture in the first-type displacement pattern and the second-type displacement pattern based on timing from the synchronizing section.