High-resolution computed tomography from efficient sampling

This paper investigates high-resolution reconstructions from efficiently sampled data in parallel-beam tomography, in particular, local tomography. A class of sampling schemes is defined and characterized, and it is shown that the standard scheme and the interlaced scheme of Cormack (Cormack A M 1978 Phys. Med. Biol. 23 1141-8) are most promising. An error analysis for the filtered backprojection algorithm for both global and local tomography is presented. The analysis provides insights on how to realize the theoretically superior resolution of the interlaced scheme in practice. A numerical experiment with real data indicates the feasibility of high-resolution local tomography using the interlaced scheme.