Upgrade of an existing 3D X-ray microscope

现有 3D X 射线显微镜的升级

• 批准号: 521113530
• 金额: --
• 依托单位: Technische Universität Dresden
• 依托单位国家: 德国
• 项目类别: Major Research Instrumentation
• 财政年份: 2023
• 资助国家: 德国
• 起止时间: 2022-12-31 至 无数据
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/521113530?language=en
• 关键词: Upgrade; existing; 3D; ray; microscope

The Dresden Center for Nanoanalysis (DCN) currently houses a microscope. The instrument has a second, light-optical magnification stage, which allows high-resolution images to be produced almost independently of the sample size. In a conventional micro X-ray tomography (micro X-ray CT) apparatus with a cone beam and only geometric magnification on a pixelated X-ray detector, the smallest reasonable resolution is limited partly by the focal spot of the source and partly by the pixel size of the detector. In devices with two-stage magnification, on the one hand, by reducing the effective pixel size, and on the other hand, by reducing the geometric magnification, imaging below the focal spot diameter is also possible. This finer scanning also allows imaging by means of propagation phase contrast, which leads to significantly higher contrast, especially for samples of low atomic number, and thus low absorption. Due to the requirements on the coherence of the (white) X-ray light as well as the limitation of the performance at low X-ray energies, these measurements usually require long measurement times. In the present application, an upgrade for the system is requested, which includes as key features a 2.5-fold stronger X-ray source, improved resolution properties of well below 1 μm while maintaining a high accelerating voltage. This allows imaging with an increased signal-to-noise ratio on the one hand, and imaging of larger sample areas than before on the other.

德累斯顿纳米分析中心 (DCN) 目前拥有一台显微镜，该仪器具有第二个光学放大级，可以在传统的显微 X 射线断层扫描中几乎独立地生成高分辨率图像。微型 X 射线 CT）设备在像素化 X 射线探测器上具有锥形束和仅几何放大倍数，最小合理分辨率部分受到源焦点的限制，部分受到设备中探测器的像素尺寸的限制。通过两级放大，一方面通过减小有效像素尺寸，另一方面通过减小几何放大倍数，也可以在焦斑直径以下成像，这种更精细的扫描还允许通过传播方式成像。相衬，这导致显着更高的对比度，特别是对于低原子序数的样品，因此由于对（白色）X射线光的相干性的要求以及低X下的性能限制而导致低吸收。 -射线能量，这些测量在当前的应用中，需要对系统进行升级，其中包括强度提高 2.5 倍的 X 射线源、将分辨率提高到远低于 1 μm，同时保持高加速电压。一方面可以提高信噪比进行成像，另一方面可以对比以前更大的样品区域进行成像。