X-ray interferometric imaging system

An x-ray transmission imaging system comprising:

• a source of x-rays comprising:
• a vacuum chamber;
• an emitter for an electron beam;
• and
• an electron target comprising:
• a substrate comprising a first material and, embedded in the substrate,
• at least a plurality of discrete structures comprising a second material selected for its x-ray generating properties,
• and in which said plurality of discrete structures;
• are arranged within a periodic pattern of sub-sources;
• a stage to position and orient an object to be examined;
• an x-ray detector comprising a two-dimensional array of x-ray detecting elements, positioned to detect x-rays transmitted through the object to be examined;
• said x-ray transmission system additionally comprising:
• a scattering rejection apparatus placed between the position of the object to be examined and the detector, comprising:
• a beam-splitting x-ray grating comprising periodic structures that form an x-ray phase-shifting grating positioned to diffract x-rays generated by the sub-sources of x-rays so that a Talbot interference pattern is formed by the interaction of the x-rays generated by the source of x-rays with the beam splitting grating;
• and
• an antiscattering grid having a periodic array of septa comprising an x-ray absorbing material positioned between the beam splitting x-ray grating and the detector;
• and
• a controller for adjusting the position of the anti-scattering grid relative to the Talbot interference pattern;
• in which the dimensions and periodicity of the septa of the antiscattering grid are selected to correspond to the dimensions of the Talbot interference pattern, and the septa of the antiscattering grid are positioned such that the septa are aligned with the nodes of the Talbot interference pattern.