Upgrade of an existing 3D X-ray microscope

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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.