Refractive-index based tomosynthesis using dark-field imaging optics

Tomosynthesis (TS) is a pseudo-3-dimensional image reconstruction method to recover depth-resolved information using restricted number of projections. In this research, refraction index based TS imaging using dark-field imaging (DFI) optics is proposed and biomedical soft tissues were imaged in low dose exposure. By a single exposure of an object, two projected images are obtained from a Laue-case analyzer of DFI. Calculating the both images refraction component is deduced, while two exposures are needed in DEI (diffraction enhanced imaging). Thus the measurement time and the radiation dose in DFI are half of DEI. In addition, the proposed reconstruction algorithm, derived from the quantitative relationship in measurement process, allows high contrast tomographic imaging in spite of one order smaller number of projections for CT (computed tomography). To demonstrate the proposed imaging protocol efficacy, an ex-vivo excised tissue of human lung were imaged using a system constructed at the vertical wiggler beamline at PF-BL14C at KEK. TS image is successfully delineated high quality soft tissue structures comparable to CT.