Inverse Fourier Transform in the Gamma Coordinate System
Figure 1
3D reconstruction problem in parallel-beam geometry and the cylindrical coordinate system. (a) A parallel-beam scans an object along a semicircle locus on the unit sphere; (b) In the frequency domain, when increases from 0 to the frequency plane scans every point exactly once except for the points on the axis, and the end point of the normal vector moves along the equator from to (0,1,0); (c) For simplicity, we suppose that the detector panel passes through the origin.