Fig. 2.

At each position, the detector acquires a projection (P) of the object (e.g., forearm). The CT reconstruction algorithm essentially averages the intensities of these multiple projections at each spot on the detector array, and generates a 2D tomogram (slice) which is like a density map. Note that for clinical CT and in vivo microCT, the source and detector rotate around the subject, as shown above. By contrast, for specimen microCT, multiple projections are acquired by rotating the object while the source and detector are fixed