Skip to main content
Fig. 1 | European Radiology Experimental

Fig. 1

From: Simultaneous wood and metal particle detection on dark-field radiography

Fig. 1

Basic principle of the experimental x-ray dark-field radiography setup. a The experimental dark-field radiography setup is based on a three grating interferometer, a so-called Talbot-Lau interferometer. The source grating G0 provides the necessary beam coherence for interference effects to occur with a clinical x-ray source, the phase grating G1 causes a periodic modulation of the interference pattern, and the analyser grating G2 enables the resolution of the pattern with a conventional detector. b The phase grating is shifted laterally in seven discrete steps leading to a resulting stepping curve for each detector pixel. Performing two scans, one without the object (reference scan) and one with the object (sample scan), leads to two different stepping curves. The conventional attenuation image is represented by the relative mean values of the curve and the relative reduction of the amplitude (which represents the visibility of the system) is a measure for the dark-field signal. c A human hand fixed in formalin was measured in preclinical x-ray dark-field setup to evaluate the diagnostic value for foreign-body detection

Back to article page