The application relates to a
system and a method for the phase-
contrast imaging by use of X-
ray gratings. The
system comprises an X-
ray device, a first absorption
grating, a second absorption
grating, a detection unit, a
data processing unit and an imaging unit, wherein the X-
ray device transmits an X-ray bundle to a detected object; the first and second absorption gratings are positioned in the direction of the X-ray bundle; the X-ray refracted by the detected object forms an X-ray
signal with
variable intensity through the first absorption
grating and / or the second absorption grating; the detection unit receives and converts the X-ray with
variable intensity into an electrical
signal; the
data processing unit processes and extracts
refraction-angle information in the electrical
signal, and utilizes the
refraction-angle information to figure out pixel information; and the imaging unit constructs images of the object. In addition, the
system and the method can also realize
CT imaging by using a rotating structure to rotate the object so as to obtain
refraction angles in a plurality of projection directions and the corresponding images, and use
CT reconstruction algorithm to figureout refraction-index fault images of the detected object. According to the invention, the phase-
contrast imaging of approximate decimeter-magnitude viewing fields under incoherent conditions can be realized by use of common X-ray machines or multi-seam
collimator such as source gratings, as well as two absorption gratings.