Apparatus for phase-contrast imaging comprising a displaceable X-ray detector element and method

An X-ray system, comprising an apparatus for phase contrast imaging, the apparatus comprising:

• an X-ray source;
• an X-ray detector element having a detector size;
• a first grating element;
• and
• a second grating element;
• wherein an object is arrangeable between the X-ray source and the X-ray detector element;
• wherein the first grating element and the second grating element are arrangeable between the X-ray source and the X-ray detector element;
• wherein the X-ray source, the first grating element, the second grating element and the X-ray detector element are operatively coupled such that a phase contrast image of the object is obtainable;
• wherein the apparatus is configured to acquire a phase contrast image having a field of view lamer than the detector size;
• wherein the X-ray detector element is displaceable;
• and
• wherein by the displacement of the X-ray detector element a phase contrast image of the field of view is obtainable.

A method for acquiring phase contrast image information, comprising acts of:

• acquiring first phase contrast image information in a first phase stepping state;
• displacing, tilting and/or rotating an X-ray detector element relative to at least one of an object and an X-ray source and displacing a first grating element and a second grating element relative to one another;
• and
• acquiring second phase contrast image information in a second phase stepping state.