An apparatus for deriving X-ray absorbing and phase information comprises; a splitting element for splitting spatially an X-ray, a detector for detecting intensities of the X-rays transmitted through an object, the intensity of the X-rays changing according to X-ray phase and also position changes, and an calculating unit for calculating an X-ray transmittance image, and an X-ray differential phase contrast or phase sift contrast image as the phase information. The X-ray is split into two or more X-rays having different widths, and emitted onto the detector unit. And, the calculating unit calculates the X-ray absorbing and phase information based on a difference, between the two or more X-rays, in correlation between the changing of the phase of the X-ray and the changing the intensity of the X-ray in the detector unit.