X-ray near-field ptychography for optically thick specimens
X-ray near-field ptychography for optically thick specimens
复制标题
用于光学厚样品的 X 射线近场叠层成像
DOI：
10.1103/physrevapplied.3.014005
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发表时间：
2015
影响因子：
4.6
通讯作者：
P. Thibault
中科院分区：
文献类型：
--
作者：
M. Stockmar;I. Zanette;M. Dierolf;B. Enders;R. Clare;F. Pfeiffer;P. Cloetens;A. Bonnin;P. Thibault
像其他无透镜成像方法一样，内嵌全息术通过后验相位恢复步骤绕过了x射线光学的限制。然而，对于光学厚度，即强吸收和相移的样品，相位恢复仍然具有挑战性。在本文中，我们证明了近场平面摄影可以有效地在直径约为46 μm的铀球上进行相位检索，该铀球作为光学厚度样品。这种特殊的样品以前是无法通过内嵌全息术访问的。重建基于统计模型，并通过将照明分解为相干模式来实现部分相干性。此外，我们观察到相位涡在重建过程中可能作为伪影出现，比远场方法带来更大的挑战。我们期望本文中描述的方法能够产生可靠的样品相图，而这些相图是无法通过内嵌全息术访问的。
Inline holography, like other lensless imaging methods, circumvents limitations of x-ray optics through an a posteriori phase-retrieval step. However, phase retrieval for optically thick, i.e., strongly absorbing and phase shifting, specimens remains challenging. In this paper, we demonstrate that near-field ptychography can be used to efficiently perform phase retrieval on a uranium sphere with a diameter of about 46 μm, which acts as an optically thick sample. This particular sample was not accessible by inline holography previously. The reconstruction is based on a statistical model and incorporates partial coherence by decomposing the illumination into coherent modes. Furthermore, we observe that phase vortices, which can occur as artifacts during the reconstruction, pose a greater challenge than in far-field methods. We expect that the methods described in this paper will allow production of reliable phase maps of samples which cannot be accessed by inline holography.
影响因子：
8.6
作者：
Clark, Jesse N.;Huang, Xiaojing;Robinson, Ian K.
通讯作者：
Robinson, Ian K.