摘要
本文在平行相干光照明条件下,推导出了二维光栅剪切成像系统的角度信号响应函数,并描绘出了角度响应函数二维曲面.虽然光栅剪切成像系统常用的分束光栅有四种,分析光栅有三种,分析光栅和分束光栅之间还存在多种不同组合,但是产生的角度信号响应函数曲面却只有三种,即峰型位移曲面、谷型位移曲面和峰谷对称型位移曲面.其中峰型位移曲面和谷型位移曲面之间具有数值互补关系,由此还可以把峰型位移曲面和谷型位移曲面归纳为一种,最终只需要考虑两种位移曲面.这个理论结果无疑显著简化了人们对二维光栅剪切成像的认识,将对今后讨论定量提取二维角度信号的工作奠定基础.
In this paper, we derive the response function of angle signal in a two-dimensional X-ray grating interferometry system under the condition of parallel coherent light, and depict the surface of the function with Matlab.Although there are four kinds of commonly used beam splitter gratings and three kinds of analyzer gratings, and there are still different compound modes between them, we may find that the ultimate surface of the response function of angle signal can only be of three kinds: the peak type, the valley type, and the peak-valley symmetry type of shifting surfaces. As there is a numerical complementary ralationship between the peak type and the valley type of shifting surfaces, we can take the two kinds as one; and finally we only need to consider two kinds of shifting surface.This conclusion simplies the common understanding of the two-dimensional X-ray grating interferometry method, and lays the foundation for the research of quantitatively extracting the two-demensional signal in the future.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2014年第7期391-401,共11页
Acta Physica Sinica
基金
国家重点基础研究专项经费(批准号:2012CB825800)
国家自然科学基金(批准号:11205189,11375225,U1332109)
中科院知识创新项目(批准号:KJCX2-YW-N42)资助的课题~~
关键词
光栅剪切成像
相位衬度成像
位移曲面
位移曲线
two-dimensional X-ray grating interferometry, phase contrast imaging, shifting surface,shifting curve