Theoretically exact FBP-type inversion algorithm for spiral CT
نویسنده
چکیده
| Proposed is a theoretically exact formula for inversion of data obtained by a spiral CT scan with a 2D detector array. The detector array is supposed to be of limited extent in the axial direction. The main property of the formula is that it can be implemented in a truly ltered backprojection fashion. First, one performs shift-invariant ltering of a derivative of the cone beam projections, and, second, the result is back-projected in order to form an image. Another property is that the formula solves the socalled \long object problem". Limitations of the algorithm are discussed. Results of numerical experiments are presented.
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