论文标题
带有随机照明的单帧远场衍射成像
Single-frame far-field diffractive imaging with randomized illumination
论文作者
论文摘要
我们引入了一种称为随机探针成像（RPI）的单帧衍射成像方法。在RPI中，样品被结构化探针场照亮，该探针场包含小于样品的典型特征大小。然后，根据所得远场衍射模式重建定量振幅和相位图像。 RPI的实验几何形状很容易实现，不需要近场光学元件，并且适用于扩展样品。当使用免费算法分析所得数据时，可以实现可靠的重建，以实现丢失的数据。为了实现这些好处，施加了与探针形成光学元件的数值光圈相关的分辨率限制。因此，当时间分辨率和可靠性至关重要时，RPI为定量X射线相成像提供了一种有吸引力的方式，但是在数十纳米中的空间分辨率就足够了。我们讨论该方法，引入重建算法，并提供两个概念验证实验：一种使用可见光，另一个使用软X射线。
We introduce a single-frame diffractive imaging method called randomized probe imaging (RPI). In RPI, a sample is illuminated by a structured probe field containing speckles smaller than the sample's typical feature size. Quantitative amplitude and phase images are then reconstructed from the resulting far-field diffraction pattern. The experimental geometry of RPI is straightforward to implement, requires no near-field optics, and is applicable to extended samples. When the resulting data are analyzed with a complimentary algorithm, reliable reconstructions which are robust to missing data are achieved. To realize these benefits, a resolution limit associated with the numerical aperture of the probe-forming optics is imposed. RPI therefore offers an attractive modality for quantitative X-ray phase imaging when temporal resolution and reliability are critical but spatial resolution in the tens of nanometers is sufficient. We discuss the method, introduce a reconstruction algorithm, and present two proof-of-concept experiments: one using visible light, and one using soft X-rays.
