An x-ray phase contrast imaging apparatus and method of operating the same. The apparatus passes x-rays generated by an x-ray source through, in succession, a source grating, an object of interest, a phase grating, and an analyzer grating. The x-ray source, the source grating, the phase grating, and the analyzer grating move as a single entity relative to an object of interest. The phase grating and the analyzer grating remain in fixed relative location and fixed relative orientation with respect to one another. The detected x-rays are converted to a time sequence of electrical signals. In some cases, the apparatus is controlled, and the electrical signals are analyzed by, by a general purpose programmable computer provided with instructions recorded on a machine readable medium. One or more x-ray phase contrast images of the object of interest are generated, and can be recorded or displayed.