用于中子相衬成像的衍射光栅的设计、制造与表征

Design, fabrication, and characterization of diffraction gratings for neutron phase contrast imaging.

作者信息

Grünzweig C, Pfeiffer F, Bunk O, Donath T, Kühne G, Frei G, Dierolf M, David C

机构信息

Paul Scherrer Institut, CH-5232 Villigen-PSI, SwitzerlandEcole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.

出版信息

Rev Sci Instrum. 2008 May;79(5):053703. doi: 10.1063/1.2930866.

DOI:10.1063/1.2930866

PMID:18513071

Abstract

We have developed a neutron phase contrast imaging method based on a grating interferometer setup. The principal constituents are two absorption gratings made of gadolinium and a phase modulating grating made of silicon. The design parameters of the setup, such as periodicity, structure heights of the gratings, and the distances between the gratings, are calculated. The fabrication of each grating is described in detail. The produced diffraction gratings were finally characterized within the setup, by locally evaluating the produced contrast (visibility) in each detector pixel, resulting in a visibility map over the whole grating size. An averaged value of 23% is achieved.

摘要

我们基于光栅干涉仪装置开发了一种中子相衬成像方法。主要组成部分是两个由钆制成的吸收光栅和一个由硅制成的相位调制光栅。计算了该装置的设计参数，如周期性、光栅的结构高度以及光栅之间的距离。详细描述了每个光栅的制造过程。最终在该装置内对所制备的衍射光栅进行了表征，通过局部评估每个探测器像素中产生的对比度（可见度），得到了整个光栅尺寸上的可见度图。平均可见度达到了23%。