DIFFERENTIAL PHASE CONTRAST IMAGING DEVICE WITH MOVABLE GRATING(S)

摘要

An X-ray differential phase contrast imaging device (10) comprises an X-ray source (20) for generating an X-ray beam; a source grating (G0) for generating a coherent X-ray beam from a non-coherent X-ray source (20); a collimator (22) for splitting the coherent X-ray beam into a plurality of fan-shaped X-ray beams (28) for passing through an object (14); a phase grating (G1) for generating an interference pattern and an absorber grating (G2) for generating a Moiré pattern from the interference pattern arranged after the object (14); and a line detector (24) for detecting the Moiré pattern generated by the phase grating (G1) and the absorber grating (G2) from the fan-shaped X-ray beams (28) passing through the object (14). The X-ray source (20), source grating (G0), collimator (22), phase grating (G1), absorber grating (G2) and line detector (24) are fixed to a common gantry (12) and are movable with respect to the object (14), such that a number of interference pattern from different positions of the gantry are detectable for reconstructing a differential phase image of the object (14). At least one grating (G0, G1, G2) comprises, in an alternating manner, groups (36) of grating lines (34) and transparent areas (38). At least one grating (G0, G1, G2) is movable with respect to the gantry (12), such that in a first position of the grating (G1, G2) the fan-shaped X-ray beams (28) pass through the grating lines (34), and in a second position of the grating (G1, G2), the fan-shaped X-ray beams (28) pass through the transparent areas (38).

主权项

1. An X-ray differential phase contrast imaging device, comprising:
an X-ray source for generating an X-ray beam; a source grating (G0) for generating a coherent X-ray beam from a non-coherent X-ray source (20); a collimator comprising slits for splitting the coherent X-ray beam into a plurality of fan-shaped X-ray beams for passing through an object; a phase grating (G1) for generating an interference pattern and an absorber grating (G2) for generating a Moiré pattern from the interference pattern arranged after the object;
a line detector comprising detector lines for detecting the Moiré pattern generated by the phase grating (G1) and the absorber grating (G2) from the fan-shaped X-ray beams (28) passing through the object;wherein the X-ray source, source grating (G0), collimator, phase grating (G1), absorber grating (G2) and line detector are fixed to a common gantry and are movable with respect to the object, such that a number of interference patterns from different positions of the gantry are detectable for reconstructing a differential phase image of the object; wherein groups of grating lines and transparent areas (38) alternate with respect to each other in a direction perpendicular to the direction of the detector lines;
wherein at least one grating (G0, G1, G2) of the source grating, the phase grating and the absorber grating comprises groups of grating lines and transparent areas between the groups of grating lines, and is movable with respect to the gantry, such thatin a first position of the source grating (G0) the X-ray beams pass through the grating lines and subsequently pass through the slits of the collimator and in a second position of the source grating (G0) the X-ray beams pass through the transparent areas and subsequently pass through the slits of the collimator, orin a first position at least one of the phase grating (G1) or the absorber grating (G2) the fan-shaped X-ray beams pass through the grating lines, and in a second position at least one of the phase grating (G1) or the absorber grating (G2) the fan-shaped X-ray beams pass through the transparent areas.