The Virtual Platform Design Of Energy Spectrum Filtering Separation Multi-spectral CT Imaging Based On Geant4

In industrial CT system, the traditional CT imaging system is prone to hardening artifacts and poor reconstruction quality and so on, which can not meet the functional requirements of the partition of the material group. Currently, multi-spectral imaging technology based on energy spectrum filtering separation has some advantages compared with the photon counting multi-spectral CT and dual energy CT, which has a certain degree of technical maturity and feasibility. The method can realize the spectral separation and imaging by adding a filter sheet,which can improve the division of the material component. But being limited by the thickness of the filter sheet, the material and its component matching, the method need to be verified and optimized by repeated experiments. Therefore, in order to improve the multi-spectral imaging method of the efficiency study, this paper uses Monte Carlo simulation technique to study multi-spectral attenuation and multi-spectral scattering model, further being integrated with Geant4 platform, designs spectrum filtering separation multi-spectral CT imaging virtual platform, and then provides a simulation and verification platform for spectrum filtering separation and theoretical Study on spectrum matching.Firstly, based on the principle analysis of CT imaging and simulation, the paper studies the corresponding ray energy spectrum simulation model, scattering simulation models and multi-spectral projection simulation model; and builds a customized software development environment on the basis of Geant4 and related software; the same time, for the design goals of the virtual platform the paper studies the modular design of each simulation model and integrates them into the interface function layers callable from each other, then being into the overall framework to build the virtual platform of multi-spectral CT imaging, and on this basis, we make a simulation experiment to verify the platform; Finally, according to the implementation process of energy spectrum filtering separation we establish corresponding projection simulation model and design a multi-spectral CT imaging virtual platform based on the Geant4 platform. The research shows that the virtual platform can realistically simulate multi-spectral CT imaging system of energy spectrum filtering separation and realize function imaging of materials group partition, and provide a simulation platform for theoretical research of the energy spectrum filtering separation and spectral matching.