3D SCATTERING TENSOR BASED ON ONE OR TWO AXES OF ROTATION
X-ray computed tomography (XCT) is a non-destructive evaluation method that is used to obtain high-resolution three-dimensional images of the internal structure of specimen. Advancements are being made for higher resolution XCT, however, there is always a tradeoff between the resolution and the size of the specimen that can be scanned. X-ray Tensor Tomography (XTT) (Malecki et al.) is a recent imaging modality that provides a solution to said trade-off. In contrast to conventional XCT where X-ray absorption is the main source of contrast, XTT utilizes the scattering of X-rays in order to analyze sub-micron sized structures inside macro-sized specimen.
Conventional XTT-systems rely on three axes of rotation in order to orient the specimen for image acquisition. To achieve this, the specimen stage needs to be positioned in an Eulerian cradle, enormously increasing the system’s complexity. Additionally, this leads to a large set of image data resulting in an extensive reconstruction process.
The present invention provides an XTT-system, which is capable of reconstructing sets of full 6D scattering tensors at each point in 3D space allowing the detection of inner specimen structures having any orientation by using only one or two specimen rotational axes (Sharma, APL).
Figure: Setup and 3D-image of a Short Fiber Reinforced Polymer (SFRP) specimen made of glass fibers (18 μm in diameter). The color scheme is coded with the orientation of the fibres.
The disclosed XTT-system provides more robustness and reliability and can be used for non-destructive material testing with several commercial advantages:
• shorter acquisition time caused by a smaller amount of specimen positions leading to a faster reconstruction procedure (Wieczorek et al.)
• reduced costs and complexity realized by a simpler specimen stage omitting the problematic rotation of the specimen due to between the gratings
Feasibility has been shown.
(1) WO 2017/216178
(2) Malecki, A., Potdevin, G., Biernath, T., Eggl, E., Willer, K., Lasser, T., Maisenbacher, J., Gibmeier, J., Wanner, A., and Pfeiffer, F. (2014). X-ray tensor tomography. EPL (Europhysics Letters), 105(3):38002.
(3) Sharma, Y., Wieczorek, M., Schaff, F., Seyyedi, S., Prade, F., Pfeiffer, F., and Lasser, T. (2016). Six dimensional x-ray tensor tomography with a compact laboratory setup. Applied Physics Letters, 109(13):134102.