Abstract
In reconstructing cross-sectional images of 2D(2-dimensional)X-ray CT, a data acquisition is a line integral operation along a projection's direction. This operation is equivalent to the Radon transform(RT), hence the reconstructing cross-sectional images is equivalent to this inverse transform. Generaly, the convolution backprojection(CB)algorithm has been used for realiging 2D inverse Radon transform(IRT). The authors proposed the method to shorten reconstructing time by using TFB for the backprojection-part. In this paper, we expand the TFB method to 3D-IRT, and show that this technique is very effective for time saving. The application to 3D-IRT realized that the reconstructing speed of TFB method was approximately about 760 times faster than that of IRT method.