Figure 2
From: Helical X-ray phase-contrast computed tomography without phase stepping
Experimental procedure of helical moiré fringe scanning.
Six interferograms (a), each recorded at the same angle but at different sample positions because of the helical movement, are combined to obtain a phase-stepping curve for each pixel. The areas marked with a red box are used to obtain a transmission, differential phase and dark-field projection (b).
