Spatial response of source--collimator--detector systems for industrial applications of computed tomography

A simple model that accurately predicts the three-dimensional spatial response of a tomography system consisting of a spherical or cylindrical radioisotopic source, an arbitrary number of rectangular apertures, and a rectangular parallelepiped detector has been developed and verified experimentally. The implementation of the model in FORTRAN is discussed. This model is suitable for industrial applications of computed tomography, and has proved to be a useful, if not essential, tool for the design of computed tomography scanners.