Fast algorithm for rotation and translation two-dimensional computed tomography accurate reconstruction

RT (rotation and translation) scan mode for 2D (two-dimensional) CT (computed tomography), based on multiple axes, can scan large-sized work pieces and components with paraxial X-ray beam. Compared with the traditional second generation scan mode of TR (translation and rotation), it can save about 3/4 times of the scan time. The accurate reconstruction algorithm by region, can remove the artifacts around inner and outer borders in general reconstruction images. But a mass of zero values participate back-projection operations, and slow down the accurate algorithm operation. In this paper, projection data are grouped according to the regions they located before being back-projected. Data are selected or not according to the regions ID determined in advance during back-projection. So zero values are kicked out by their locations, before doing some time-consuming works such as reading, judging or accumulating the values and so on. And computer simulations show that the reconstruction algorithm saves at least half of the operation time according to the number of rotation centers.