X-ray transmission imaging that creates image contrast from the distribution of the X-ray absorption coefficient is not sensitive to materials consisting of light elements such as hydrogen, carbon, nytrogen, and oxygen. On the other hand, the X-ray phase shift caused by the light elements is substantial enough to be detected even when absorption is almost zero. Hence, phase-contrast X-ray imaging is a promissing technique for observing the structure inside biological soft tissues without the need for staining and without serious radiation exposure. Using fringe scanning X-ray interferometry, the X-ray phase shift caused by an object was measured. Three-dimensional image reconstruction of cancerous tissues using the measured phase shifts was enabled under tomographic configuration phase-contrast X-ray computed tomography (CT) .
