Figure 2.

Circular field of view (FOV) and recoverable regions of interest (ROI) according to different data sufficiency conditions. (a) A small recoverable region per the condition by Noo et al., (b) the enlarged recoverable region per the condition by Defrise et al., (c) and (d) the recoverable region per our new data sufficiency condition when the FOV is contained in the convex hull of the compact support of the object and covers a part of known region. The dashed lines outline the FOV. The gray-region represents the recoverable ROI, where the exact reconstruction can be performed.