Backprojection for x-ray CT system

摘要

An x-ray CT system acquires a series of views during a scan and reconstructs a slice image by backprojecting the filtered projection data from each acquired view. Backprojection is facilitated by employing a Cordic processor that produces the angle ( gamma ) and distance (L) of each pixel location from the x-ray source. The angle ( gamma ) selects the proper value from the filtered projection data, and this value is divided by the square of the distance (L) to arrive at a value used to update the slice image pixel value.