Abstract:

The reconstruction ranges of various cone-beam source trajectories are mathematically described based on the R-line algorithm , and the definition and existence of the reconstruction ranges are studied. Then , the section characteristics of the reconstruction ranges of several typical trajectories such as orthogonal double circles , helix and saddle trajectories are investigated. The effect of trajectory discretization on the reconstruction accuracy is finally discussed. Experimental results show that the sets of reconstructed points are controlled by the geometric parameters of the reconstruction range , and that the reconstructed points after the trajectry discretization non-uniformly distribute with an uneven reconstruction error distribution.

Key words: cone-beam reconstruction, reconstruction range, trajectory geometry, reconstruction accuracy, Computed Tomography