The laboratory supports Users of the neutron imaging instrument CONRAD II and provides the possibility to perform imaging experiments with complementary X-ray imaging techniques. The micro spot X-ray source produces a cone beam which allows for different magnification ratios in dependence of the relation between source-detector and source-sample distances. In this way the field of view and the spatial resolution are tunable. The short exposure times allow for fast preliminary image tests of samples which are dedicated for neutron tomographic experiments.
- Radiography: Projection Images of samples. The result is a 2D image that displays the local X-ray transmission of the sample. The resolution is tunable between 5 µm and 50 µm corresponding to fields of view (sample sizes) between 1 cm and 10 cm. The exposure time varies between 1 s and 10 s per image.
- Tomography: Three-dimensional visualization of the inner structure of a sample by volumetric mapping of the matrix of attenuation coefficients. The result is 3D digital volume which can be analyzed by rendering software. The spatial resolution is tunable between 10 µm and 50 µm. The sample sizes are similar to the radiography experiments. The tomographic experiment takes between 30 minutes to 3 hours in dependence on the sample material.
- Phase-contrast tomography: The technique uses a refraction contrast which can provide better result than absorption contrast for some special cases. For the reconstruction of the phase-contrast data a special software routine is used (AnkaPhase). The experiment parameters are similar to that of conventional tomography with the only difference that the distance between the sample and the detector should be increased which leads to small region of interest (sample size) and larger exposure times.
- Laminography: The x-ray computed laminography is developed as a method for high-resolution three-dimensional (3D) imaging of regions of interest (ROIs) in all kinds of laterally extended samples. In comparison to computed tomography, the method is based on the inclination of the tomographic axis with respect to the incident X-ray beam by a defined angle. The experiment parameters are similar to that of conventional tomography.
Source: x-ray tube (Hamamatsu, L8121-03), Voltage: 40-150 kV, spot sizes: 7 µm, 20 µm and 50 µm
Detector: flat panel (Hamamatsu, C7942SK-05) with 2316x2316 pixels and a resolution of 50 µm.
Equipment: High-pressure cell (100 bar), furnace (800°C)