Open AccessAchieving diffraction-limited nanometer-scale X-ray point focus with two crossed multilayer Laue lenses: alignment challenges
Author(s) -
Hongyuan Yan,
Xiaojing Huang,
Nathalie Bouet,
Juan Zhou,
Evgeny Nazaretski,
Yong S. Chu
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.025234
Subject(s) - optics , focus (optics) , diffraction , orthogonality , azimuth , astigmatism , physics , point (geometry) , ptychography , scale (ratio) , aperture (computer memory) , x ray optics , x ray , geometry , mathematics , quantum mechanics , acoustics
We discuss misalignment-induced aberrations in a pair of crossed multilayer Laue lenses used for achieving a nanometer-scale x-ray point focus. We thoroughly investigate the impacts of two most important contributions, the orthogonality and the separation distance between two lenses. We find that misalignment in the orthogonality results in astigmatism at 45° and other inclination angles when coupled with a separation distance error. Theoretical explanation and experimental verification are provided. We show that to achieve a diffraction-limited point focus, accurate alignment of the azimuthal angle is required to ensure orthogonality between two lenses, and the required accuracy is scaled with the ratio of the focus size to the aperture size.