Principles of Computerized Tomographic Imaging
نویسنده
چکیده
The total attenuation suffered by one beam of x-rays as it travels in a straight line through an object can be represented by a line integral. Combining a set of line integrals forms a projection. With the filtered back projection a three-dimensional reconstruction of the object can de made by using projections from different angles. The quality of a reconstructed image depends on the number of samples, the number of projections, the reconstruction grid, the photon energy, the x-ray source and the detector. Several techniques can be used to avoid or repair distortions. To improve the volume coverage speed performance of CT scans, new scanning methods, such as helical and multi-slice CT, are developed. These methods ask for new reconstruction algorithms.
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