Elimination of wraparound artifacts in spatial harmonic imaging using motion blurring

Dark-field X-ray imaging (DFXI), which is based on spatial harmonic imaging (SHI), is an imaging modality that can rapidly and easily acquire microstructural information on macroscopic samples that cannot be detected by conventional X-ray imaging systems. It has potential in various fields. However, it cannot obtain accurate information concerning microstructures, owing to image distortion caused by wraparound artifacts. In this study, we examined the use of motion-blurring technique to eliminate these artifacts and devised a modified motion condition for a tilted grid system designed to prevent moiré artifacts in SHI-based DFXI. Experimental results indicated that the technique successfully eliminated the artifacts in dark-field images and increased the contrast-to-noise ratio for small-angle X-ray scattering signals, which are the measures of microstructural information of the sample. Furthermore, the technique increased the accuracy of detection of low-density foreign bodies in SHI-based DFXI-particularly when the sample had sharp edges. The results indicate the applicability of motion-blurring technique to SHI-based DFXI.