Speaker
Description
X-ray phase contrast imaging: An alternative approach to laboratory-based sources
Gideon Chinamatira1, Kudakwashe Jakata2, Hillary Masenda1, Josephine Gutekunst3, Anton Du Plessis4,5
1University of the Witwatersrand, 1 Jan Smuts Ave, Braamfontein, Johannesburg, 2000, South Africa
2Diamond Light Source, Harwell Science and Innovation Campus, Fermi Ave, Didcot OX11 0DE, United Kingdom
3Microworks GmbH, Schnetzlerstr. 9, 76137 Karlsruhe, Germany
4Stellenbosch University, 41 Merriman Street, Stellenbosch, Western Cape, South Africa,
5Comet Technologies Canada Inc, Montreal, Canada
Corresponding author e-mail address: gideonchinamatira@gmail.com
- Introduction
Conventional X-ray imaging, based on the absorption of X-rays by various materials, is the standard technique for non-destructive inspection of internal structures. This method is effective for high X-ray attenuation scenarios but encounters limitations when applied to specimens which often exhibit weak absorption contrast due to similar densities among their components [1]. To address this challenge, methods generating radiographic contrast from X-ray phase shifts and scattering have been explored. Among these, grating-based interferometric techniques, specifically the Talbot-Lau interferometer, show significant promise for laboratory-based phase contrast X-ray imaging. This technique employs a series of gratings to create an interference pattern that encodes phase information, enabling the visualization of structures with low absorption contrast [2]. This type of interferometer is particularly suited for use with polychromatic X-ray sources commonly found in laboratory settings due to the introduction of an additional source grating which introduces spatial coherence to the X-ray beam. The spatial coherence is essential for creating well-defined interference patterns downstream in the system setup [3]. In this work, we make use of the Talint-EDU system, a ready to use Talbot-Lau-Interferometer, for implementation to our already existing X-ray computed tomography imaging setup. We conducted a series of characterization experiments to evaluate the effectiveness of our system. These experiments included angular X-ray transmission measurements, system visibility measurements, phase stepping and stability tests, and an assessment of the system's sensitivity as a function of distance from the phase grating. Through these experiments, we were able to optimize the performance of the Talbot-Lau interferometer and ensure reliable imaging results
- Results
To demonstrate the capabilities of the system, we obtained preliminary images of a pencil and a circuit board. These images showcase the system's ability to obtain phase contrast, absorption, and dark-field imaging and highlight the potential of the Talbot-Lau interferometer system to overcome the limitations of conventional X-ray imaging offering a powerful tool for applications in various research and industrial environments.
- References
[1] T. Weitkamp, A. Diaz, C. David, F. Pfeiffer, M. Stampanoni, P. Cloetens, and E. Ziegler. X-ray phase imaging with a grating interferometer. Optics Express, 13 (2005) 6296-6304.
[2] H. Wen. Biomedical X-Ray Phase-Contrast Imaging and Tomography. In: P.W. Hawkes, J.C.H. Spence (eds) Springer Handbook of Microscopy. Springer Handbooks. Springer, Cham (2019).
[3] S.A. McDonald, F. Marone, C. Hintermüller, G. Mikuljan, C. David, F. Pfeiffer, and M. Stampanoni. Advanced phase-contrast imaging using a grating interferometer. Journal of Synchrotron Radiation, 16 (2009) 562-572.
