多光束叠层衍射成像中的分辨率匹配增益
Resolution-matched gain in Multi-beam ptychography
- Lund University（隆德大学）
- MAX IV Laboratory, Lund University（马克斯四实验室，隆德大学）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
本研究通过数值模拟比较单光束与多光束叠层衍射成像，发现多光束在相同分辨率下图案数更少，增益约两倍，且增益受探测信息与重建标准影响。
AI中文摘要：
单光束叠层衍射成像（SBP）需要重叠的扫描位置以实现可靠重建，而成像更大区域则需要更多测量。多光束叠层衍射成像（MBP）同时照射多个区域，但当不同光束的衍射强度在探测器上重叠时，其在固定分辨率下的测量增益仍不明确。通过数值模拟，我们通过改变SBP和最多15束完全重叠MBP的扫描步长，确定了达到目标分辨率所需的最小图案数量。我们将增益定义为在相同总成像面积和达到的分辨率下，重复SBP扫描的图案数量除以MBP的图案数量。尽管所需的MBP图案数量随光束数量近似线性增加，但仍低于重复SBP扫描的数量。在空间奈奎斯特频率的67%处使用一位阈值时，完全重叠的MBP实现了约两倍的增益。探测器裁剪和较低分辨率目标降低了此增益，表明其依赖于可用的衍射信息和重建标准。由于重叠强度无法提供各光束贡献的空间识别，此增益是保守基准；探测器上的分离为实现更大增益提供了途径。
英文摘要：
Single-beam ptychography (SBP) requires overlapping scan positions for reliable reconstruction, and imaging larger areas demands more measurements. Multi-beam ptychography (MBP) illuminates several regions simultaneously, but its measurement gain at a fixed resolution remains unclear when diffraction intensities from different beams overlap on the detector. Using numerical simulations, we determined the minimum number of patterns needed to reach a target resolution by varying the scan step size for SBP and fully overlapped MBP with up to 15 beams. We define gain as the pattern count for repeated SBP scans divided by that for MBP at the same total imaged area and achieved resolution. Although the required MBP pattern count increased approximately linearly with beam number, it remained below that of repeated SBP scans. At 67% of the spatial Nyquist frequency using a one-bit threshold, fully overlapped MBP achieved a gain of approximately two. Detector cropping and lower-resolution targets reduced this gain, showing its dependence on usable diffraction information and the reconstruction criterion. Because overlapping intensities provide no spatial identification of individual beam contributions, this gain is a conservative benchmark; separation on the detector offers a route to larger gains.
