微分相衬成像阵列光源

Arrayed Source in Differential phase Contrast Imaging

通过对用于微分相衬成像吸收光栅效率及光源空间相干性分析,提出一种新型阵列光源替代现有普通光源加吸收光栅模式.根据相位光栅自成像强度分布及吸收光栅效率对干涉成像对比度的影响分析,吸收光栅厚度一般应大于100μm,而目前微加工工艺难以完成所要求的吸收光栅结构.结合光源亮度及成像对比度分析,给出阵列优化结构,并制作该光源,相关测试验证其可行性.

An arrayed X-ray source rather than traditional X-ray tube with absorption mask was proposed to generate structured light,based on the analysis of grating absorption efficiency and the coherence of X-ray source.According to the intensity distribution of interferogram,the influence of absorption efficiency on visibility of interference fringes was presented.With respect to the state of art micro-fabrication,it was impossible to realize the absorption grating required.The optimal structure of arrayed source was given from the analysis of spatial coherence.In order to verify the feasibility of the method,an arrayed X-ray tube was fabricated and relative measurement was performed.