Esposito Michela, Massimi Lorenzo, Buchanan Ian, Ferrara Joseph D, Endrizzi Marco, Olivo Alessandro
Department of Medical Physics and Biomedical Engineering, University College London, Malet Place, Gower Street, London WC1E 6BT, United Kingdom.
Rigaku Americas Corporation, 9009 New Trails Drive, The Woodlands, Texas 77381, USA.
Appl Phys Lett. 2022 Jun 6;120(23):234101. doi: 10.1063/5.0082968. Epub 2022 Jun 8.
We report on the development of a low-energy x-ray phase-based microscope using intensity-modulation masks for single-shot retrieval of three contrast channels: transmission, refraction, and ultra-small-angle scattering or dark field. The retrieval method is based on beam tracking, an incoherent and phase-based imaging approach. We demonstrate that the spatial resolution of this imaging system does not depend on focal spot size nor detector pixel pitch, as opposed to conventional and propagation-based x-ray imaging, and it is only dependent on the mask aperture size. This result enables the development of a multi-resolution microscope where multi-scale samples can be explored on different length scales by adjusting only the mask aperture size, without other modifications. Additionally, we show an extended capability of the system to resolve periodic structures below the resolution limit imposed by the mask apertures, which potentially extends dark-field imaging beyond its conventional use.
我们报告了一种基于低能X射线相位的显微镜的开发情况，该显微镜使用强度调制掩模来单次获取三个对比度通道：透射、折射以及超小角散射或暗场。该检索方法基于光束跟踪，这是一种非相干且基于相位的成像方法。我们证明，与传统的基于传播的X射线成像不同，该成像系统的空间分辨率既不取决于焦斑尺寸，也不取决于探测器像素间距，而仅取决于掩模孔径大小。这一结果使得开发一种多分辨率显微镜成为可能，通过仅调整掩模孔径大小，无需其他修改，就可以在不同长度尺度上探索多尺度样本。此外，我们展示了该系统扩展的能力，能够分辨低于掩模孔径所施加分辨率极限的周期性结构，这有可能将暗场成像扩展到其传统用途之外。
