微焦点锥束CT高分辨率成像品质控制方法研究

This project is aimed at the three-dimensional non-destructive testing for micro structures in complex components with micro-focus cone-beam CT, and focused on the problem that the actual imaging result is very far from the theoretical prediction accuracy when the high resolution is required. In order to obtain the high-resolution imaging quality control method of micro-focus cone-beam CT, the key technologies in micro-focus cone-beam CT scan, which are adaptation parameters selection and optimization, system scatter precision measurement and correction, and three-dimensional weighted reconstruction in large cone angle imaging, will be studied and realized. This will reveal the influence and balance mechanisms of scanning parameters to high-resolution imaging in micro-focus cone-beam CT, clarify the precise scatter distribution and its impacting mechanism to imaging resolution, and form the scientific and effective theory and method to control the imaging quality of micro-focus cone-beam CT. With the ability of fast acquiring high-resolution, high-accuracy and three-dimensional slice images of micro structures, the project will provide a precise, reliable and efficient data acquisition means for the comprehensive three-dimensional non-destructive testing, to meet the urgent needs of the analysis and evaluation for micro structures in complex components in high-end manufacturing.

本项目面向复杂构件微小结构的微焦点锥束CT三维无损检测，针对高分辨率成像时发现的实际成像效果与理论预测精度相差甚远的问题，研究微焦点锥束CT的高分辨率成像品质控制方法，通过微焦点锥束CT扫描的自适应参数选取与优化、系统散射的精密测量与校正、大锥角成像的三维加权修正重建等关键技术的研究与实现，揭示微焦点锥束CT扫描参数对高分辨率成像的影响规律及平衡机制，阐明微焦点锥束CT成像的精密散射分布特性及分辨率影响机制，形成一套科学有效的控制微焦点锥束CT成像品质的理论和方法，从而实现微小结构的高分辨率、高准确性三维切片图像快速获取，为微小结构的三维无损综合质量评估提供一种精密、可靠、高效的数据获取手段，以满足高端制造对复杂构件微小结构分析评估的迫切需求。

本项目面向复杂构件微小结构的微焦点锥束CT三维无损检测，针对高分辨率成像时发现的实际成像效果与理论预测精度相差甚远的问题，开展了微焦点锥束CT高分辨率成像品质控制方法研究，完成了微焦点锥束CT扫描参数分析与优化、系统散射的精密测量与校正、大锥角成像的三维加权修正重建等主要研究内容，揭示了微焦点锥束CT扫描参数对高分辨率成像的影响规律及平衡机制，阐明了微焦点锥束CT成像的精密散射分布特性及分辨率影响机制，为微小结构的三维无损综合质量评估提供了一种精密、可靠、高效的数据获取手段，对满足目前高端制造对复杂构件微小结构分析评估的迫切需求具有重要的理论意义和工程应用价值。.本项目的特色和主要创新点如下：.1、揭示了微焦点锥束CT扫描参数对高分辨率成像的影响规律及平衡机制，并提出了一种基于核心成像关系的微焦点锥束CT扫描参数选取与优化方法，有效确保了微小结构精密成像的原始投影质量。.2、提出了一种基于交错小孔阵列屏蔽板的锥束CT散射精密测量方法，无需复杂计算即可同时完成X射线散射和可见光散射的高精度测量与校正，进而得到了微焦点锥束CT成像的精密散射分布特性及分辨率影响机制。.3、提出了一种基于三维加权修正的锥束滤波反投影重建算法，通过构建无需重排、形式确定、实现简便的三维加权函数，显著提高了微焦点锥束CT在较大锥角扫描下的微小结构三维图像重建精度。.本项目发表论文14篇（其中SCI索引7篇，EI索引7篇），申请国家发明专利4项，培养毕业博士2名，毕业硕士5人。