Figure 1
From: 3D chemical imaging in the laboratory by hyperspectral X-ray computed tomography
Hyperspectral XCT: A regular area detector in a commercially available microtomography scanner is replaced with a spectroscopic imaging detector with a high energy resolution.
The absorbed X-ray spectrum in each pixel can now be measured. A geometric magnification can be defined by moving the sample closer to the X-ray source enabling micrometer scale resolution. By recording projections at different angles of sample rotation, a 3D dataset of the sample object can be mathematically reconstructed. Each voxel now contains an absorption spectrum as opposed to a grayscale value. Step-changes in the absorption spectrum signify the position of absorption edges, which can be used to map the distribution of chemical elements inside the object with micron scale resolution.
