CT重构中射线硬化的校正研究

Method of beam hardening correction for CT reconstruction

在工业CT(ComputedTomography)重构中,由于射束硬化使得重建图像中出现"杯状"伪影。为了消除这种影响,提出了一种校正方法。该方法基于Beer理论,根据多色射束和数据,首先拟合出等效单色射束和数据,然后进行卷积反投影重构。这种方法不仅较好地消除了射线硬化的影响,同时也使重构图像的信息损失不大。

In order to eliminate the affects of beamhardening which causes the cuplike artifacts in ICT(Industrial Computed Tomography) reconstruction, a method of beamhardening correction is introduced. This method is based on Beer's law. According to the polychromatic data, it results in equivalent monochromatic data through data fitting, then the filtering backprojection is performed and the negative affects of beam hardening are decreased considerably,and at the same time, the useful information of the image is not lost.