Diffracting aperture based differential phase contrast for scanning X-ray microscopy
Diffracting aperture based differential phase contrast for scanning X-ray microscopy
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DOI：
10.1364/oe.10.001111
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发表时间：
2002-10-07
期刊：
影响因子：
3.8
通讯作者：
Wilhein, T
中科院分区：
文献类型：
--
作者：
Kaulich, B;Polack, F;Wilhein, T
研究表明，在基于波带片的扫描X射线显微镜中，无需在普通显微镜上增加任何额外的光学元件，就可以在介观尺度上对低吸收、非均匀物质成像，从而实现差分相位衬度(DPC)。DPC模式是通过适当定位和对准显微镜孔径而简单地产生的。来自光圈的衍射产生了强度不均匀的波前。位于强度梯度上的针孔光电二极管记录的信号对被记录样品引入的相变高度敏感。在欧洲同步辐射装置(ESRF)的ID21光束线上，用6keV光子能量工作的扫描X射线显微镜验证了这种新型DPC技术的可行性。我们观察到一种差分相位对比度，类似于光学显微镜的Nomarski差分干涉对比度，这导致在成像低吸收样品时图像对比度大幅增加高达20%。(C)2002年美国光学学会。
It is demonstrated that in a zone plate based scanning X-ray microscope, used to image low absorbing, heterogeneous matter at a mesoscopic scale, differential phase contrast (DPC) can be implemented without adding any additional optical component to the normal scheme of the microscope. The DPC mode is simply generated by an appropriate positioning and alignment of microscope apertures. Diffraction from the apertures produces a wave front with a non-uniform intensity. The signal recorded by a pinhole photo diode located in the intensity gradient is highly sensitive to phase changes introduced by the specimen to be recorded. The feasibility of this novel DPC technique was proven with the scanning X-ray microscope at the ID21 beamline of the European Synchrotron Radiation facility (ESRF) operated at 6 keV photon energy. We observe a differential phase contrast, similar to Nomarski's differential interference contrast for the light microscope, which results in a tremendous increase in image contrast of up to 20% when imaging low absorbing specimen. (C) 2002 Optical Society of America.