Fig. 2: Design and implementation of the dark-field chest X-ray prototype.
From: Dark-field chest X-ray imaging for the assessment of COVID-19-pneumonia
a Schematic and b photograph of the prototype system, combining a conventional radiography setup with a three-grating X-ray interferometer. c Schematic and d photograph of the G2 grating holder allowing individual positioning of the gratings as well as bending of the gratings according to the cone-beam geometry. Bending prevents the shadowing of the gold bars of the high aspect ratio gratings. e Simulated visibility for optimising of grating parameters such as duty cycle and height. The optimisation was carried out iteratively for all three gratings. f Angular X-ray transmission measurements and scanning electron microscopy image (inlet) for one of the grating structures. g Influence of a number of fringes per frame on mean interferometric visibility.
