It is well known that X-rays can penetrate opaque objects and show the internal structure without destroying the object. Thus, X-rays are widely used for medical imaging, security and industrial inspection to name a few examples. In addition, X-ray computed tomography (CT) is a powerful technique for visualizing internal structure of various specimens including the human body, in three dimensions (3D). Recently, a high spatial resolution X-ray microscope has been developed as a result of improvements in microfocus X-ray sources and high resolution X-ray detectors, making it possible to determine the precise internal 3D structure at micrometer resolution. Rigaku has developed a unique 3D X-ray microscope, the nano3DX, by the application of the quasi-parallel beam technique with a rotating anode high-power X-ray source and submicron-resolution X-ray detector. An additional feature of the nano3DX is that it provides the ability to obtain high-contrast CT images for low-Z materials utilizing relatively low energy X-rays, e.g., Cu or Mo characteristic radiation. This feature of the nano3DX makes it very well suited for structural studies and/or inspection of various low-Z materials, e.g., polymer composite, pharmaceutical tablets, biomaterials and foods. Conventional X-ray microscopes use high energy tungsten white radiation to probe the specimen. The high energy X-rays make it difficult to distinguish constituent low-Z components from each other due to their low absorption. In addition, there is also demand for precise investigation of structural changes induced by changes in environmental conditions, for example, temperature variations or application of compression or tensile stress. In order to investigate structural changes under real environmental conditions, it was necessary to build in situ attachments, which can be combined with CT measurements.
Kazuhiko Omote, Yoshihiro Takeda, Raita Hirose and Joseph D. Ferrara