FIELD: physics.
SUBSTANCE: invention relates to X-ray engineering. A device for forming a phase-contrast image for investigating an object (100) of interest comprises a source (101) for generating a radiation beam; a detector (102) for detecting radiation after passing through the object of interest (103); a first phase grating (104), situated between the source (101) and the detector (102) and having a first spacing; a second phase grating (105) situated between the source (101) and the detector (102) and having a second spacing; wherein the first spacing is different from the second spacing; wherein the first spacing corresponds to a first radiation energy; the second spacing corresponds to a second radiation energy; the first phase grating (104) has a Talbot length for the first energy; and the second phase grating (105) has the same Talbot length for the second energy. The image forming device therefore provides phase-contrast information for two different energies.
EFFECT: enabling use of phase information in a wider energy band.
14 cl, 4 dwg
