In photoacoustic imaging, there has been a possibility that an artifact is indistinguishable from an image of an actually-existing light absorber (i.e., an actual image) and the light absorber is determined to be present although nothing exists in fact. An artifact attributable to a band of an acoustic wave receiver is distinguished or reduced based the positional relationship among respective voxel data representing an actual image and a reflected image of a light absorber and related artifacts, as viewed on image data, by utilizing acoustic wave reflecting surface disposed in a specimen.
