Design of CT Reconstruction Software Based on the Air Container CT Inspection System Available to Purchase

The air container CT inspection system has been developed as a high space-resolution, high density-resolution CT scanner. The design of CT reconstruction software based on the system uses the back project algorithm to construct the CT images, and the filter functions are also included to process the CT data. Because the system can be used to inspect the large objects that cannot be penetrated easily by gamma-ray, the reconstructed CT images may have some artifacts that may damage CT image. The digital subtraction method is used to realize the CT reconstruction for the edge parts of large object that has big gamma-ray attenuation in the center part of the object. The nonlinear effect while measuring is corrected using serials of thin ion plates. The CT images for large objects are improved obviously by using the plate correction. The CT images based on the back project algorithm are also obtained by using the non-perfect projection data. The obtained CT image can have a certain precision to meet the demand. And the principal of the CT reconstruction using the non-perfect project data is also analyzed. The noise influence to the CT imaging quality is also analyzed. Different kinds of noises were added to the signals of all channels or selected channel. The experiment showed that the CT construction realized by the paper has high density resolution and high spatial resolution. The designing for CT construction software is successful.