Industrial Ct Projection And Offset Scan Reconstruction

Industrial Computed Tomography (ICT) technology is key detect technology for national defence, aviation and other industrial products manufacture. In the actual industry application, size of many components are very large that cause the detector can't acquire the whole projection data, thus produce the problem of reconstruction from incompletely projection data. To solve the problem, based on analysis of basic CT theories and algorithms, the paper studied the squashing algorithm and the improved squashing algorithm that under limited angle projection of incompletely projection data firstly. By simulation, result of experiment and strict mathematical deduce, the paper pointed out the inherent flaw of the squashing algorithm and the deficiency of the improved squashing algorithm, presented the improvement method of the squashing algorithm again. Secondly, to aim at large size component, the paper presented various bias scanning way under the case of parallel beam and fan beam. By simulation, the results of each different bias scanning way are also analyzed and compared. Finally, the algorithm of the part district reconstruction of large size component is studied when it adopt fan beam. Satisfactory simulation result is gained.