Directional X‐Ray Scattering and Microtomography for Laboratory‐Based Imaging of Fibrous Materials and Biological Tissues

X‐ray microtomography enables nondestructive three‐dimensional imaging, yet conventional attenuation contrast provides limited sensitivity to microstructural organization below the system's spatial resolution. Dark‐field imaging addresses this limitation by detecting scattering from unresolved structures, enabling indirect access to sub‐resolution features across large fields of view. Here we present a compact laboratory‐based X‐ray microtomography approach capable of resolving attenuation, phase, and anisotropic scattering signals with micrometre‐scale resolution across centimeter‐scale samples. The method employs a single intensity modulator and is compatible with conventional X‐ray sources and detectors. A key element of our system is its sensitivity to scattering along two orthogonal directions in the image plane, enabling the measurement of scattering anisotropy with a single exposure. As well as simple and robust, the approach provides sensitive and precise measurements of directional scattering signals. We demonstrate its capabilities across engineering and biological systems, including fiber‐reinforced composites, wood, bovine intervertebral discs, rat hearts, and porcine meniscus. In these samples, dark‐field tomography reveals microstructural heterogeneity and fiber‐related organization well below the voxel size that are not accessible with attenuation or phase contrast alone. These findings demonstrate the potential of the approach for nondestructive three‐dimensional characterization of complex materials and biological tissues across engineering and biomedical research.