Fig. 1. Schematic of X-ray single grating phase-contrast imaging

Fig. 2. Flow chart of phase retrieval

Fig. 3. Example diagram of Moiré artifacts. (a) Spectrum after adding object; (b) phase-contrast image with Moiré artifacts

Fig. 4. Formation of Moiré fringes. (a) Schematic; (b) diagram of geometric relation

Fig. 5. Inclination angle of Moiré fringe versus included angle of grating

Fig. 6. Frequency of Moiré fringe versus projection frequency of grating under different included angles of grating. (a) Sampling frequency is 4 pixel·mm^-1; (b) sampling frequency is 5 pixel·mm^-1

Fig. 7. Imaging results of rotating grating experiment. (a) Spectrogram before rotating grating; (b) differential phase-contrast image before rotation; (c) spectrogram after rotating grating; (d) differential phase-contrast image after rotation

Fig. 8. Phase-contrast imaging results of PU tubes with different projection frequencies of grating. (a) 3.82 line·mm^-1 (u_s=3.5u_g); (b) 3.34 line·mm^-1 (u_s=4u_g); (c) 2.67 line·mm^-1 (u_s=5u_g)

Fig. 9. Phase-contrast imaging results of chicken wings with different projection frequencies of grating. (a) 3.82 line·mm^-1(u_s=3.5u_g); (b) 3.34 line·mm^-1(u_s=4u_g); (c) 2.67 line·mm^-1(u_s=5u_g)