Exact Filtered Back Projection (FBP) Algorithm for Spiral Computer Tomography with Variable Pitch [US]

Reconstructing images of objects spirally scanned with two-dimensional detectors with a novel algorithm under a variable pitch (nonconstant speed), where the object is not restricted to moving at a constant velocity. The object can move at variable speeds(increasing, decreasing, combinations thereof) during the scan of the object. The image reconstruction process is proven to create an exact image of the object under the ideal circumstances. The algorithm can have a convolution-based FBP (Filtered Back Projection) structure and works very efficiently. The algorithm uses less computer power and combines the benefits of Exact Algorithms and Approximate algorithms. An object can be moved at a nonconstant speed through a rotating source and oppositely located detector. Additionally, at least one source and oppositely located detector can be mounted on a coil stand for generating the spiral scan