Computed laminography has become a popular tool to achieve high spatial resolution in three-dimensional imaging of flat, laterally extended objects. This study explores the synergy of synchrotron full-field micro-computed and scanning x-ray fluorescence laminography imaging, along with efficient data analysis software, to enhance x-ray imaging capabilities at beamlines 2-BM and 2-ID-E of the Advanced Photon Source at Argonne National Laboratory. We discuss the advantages of laminography imaging and demonstrate examples of laminography data acquisition and reconstruction for a flat mouse bone section measured at both beamlines. Reconstructed data provided structural information from the full-field micro-computed laminography measurements and elemental distribution from the fluorescence laminography measurements. Dragonfly ORS software was used to produce high-quality interactive volume and multichannel visualizations, facilitating the analysis of the 3D reconstructed data. The proposed integration of these two modalities for efficient structural and elemental analyses of samples holds the potential for substantial advancements in imaging technology.
The Advanced Photon Source Upgrade (APS-U) project is set to revolutionize hard x-ray research. The upgraded machine will provide increase coherent flux and brightness in x-ray beams by a factor of 500. Many x-ray techniques will significantly benefit from this enhancement, particularly in terms of speed and achievable resolution. The Imaging Group at APS operates three specialized beamlines—2-BM, 7-BM, and 32-ID—focused on full-field imaging and ultra-high-speed applications. These beamlines cover up to three orders of magnitude in both spatial and temporal resolution. As part of the APS-U, the Imaging Group will further improve its capabilities, especially in terms of speed and image quality. These advancements will enable new possibilities for researchers conducting multi-scale, multi-modal, and time-resolved experiments. A significant addition to the group will be the future installation of a Projection Microscope at 32-ID, which will bridge the resolution gap between nano-tomography, currently achieved with the Transmission X-ray Microscope at 32-ID, and micro-tomography at 2-BM and 7-BM.
Nano-CT enables 3D imaging of micro/nano-structures and is becoming an indispensable tool. At such a high resolution, specimens must have a small diameter small enough to fit into the instrument’s field of view, typically a few tens of micrometers to a few hundred micrometers. As a result, samples are commonly glued to the tip of a steel pin for alignment before imaging. Ideally, data are collected from the part of a specimen above the pin and the x-ray opaque pin will not interfere with imaging. However, the tiny sample size makes precise mounting very tricky, and many times a region adjacent to the pin is found of to be of interest post mounting. Sometimes the sample is too fragile to remount and other times removing the specimen and repeating the tedious remounting steps is impractical due to time constraints, we find that the information occluded by the metal pin can be almost fully recovered via iterative reconstruction with simple metal-trace masked from a regular scan of an imperfectly mounted specimen. Specifically, combining the metal artifact reduction and interior tomography techniques, a metal trace mask in the sinogram is first extracted from a low-resolution global reconstruction which covers the whole cross-section of the pin, then the desired high-resolution reconstruction of a region of interest is iteratively reconstructed excluding any contribution from the metal trace. Our method is demonstrated with a 42.35 nm reconstruction of a portion of a sea urchin tooth, which is scanned on a synchrotron with the pin moving across the field of view during sample rotation, showing that streaking artifacts caused by pin occlusion can be greatly suppressed to achieve an image quality close to that without occlusion. These results suggest that our method has a great potential in simplifying the specimen preparation and relaxing the proficiency requirements, which significantly facilitates nano-CT imaging applications.
Dogfish (Squalus spp.) possess one or two dorsal-fin spines located at the dorsal midline over the vertebral column. These spines are heavily mineralized, and surface bands of light and dark contrast are used in age determinations. The interior of the spine also contains growth bands visible via optical microscopy of thin sections, but the three-dimensional pattern of growth bands does not appear to have been quantitatively mapped nor has the microstructural origin of the band contrast been established. This paper reports synchrotron microComputed Tomography (microCT) results on spines of Squalus suckleyi. MicroCT was performed at beamline 2-BM of the Advanced Photon Source (APS). There are numerous parallel bands, and their contrast consists of varying (higher and lower) values of linear attenuation coefficient, similar to growth bands observed in other mineralized tissues including mammalian cementum and dentin. The microCT data are supplemented by x-ray excited x-ray fluorescence maps of a sectioned Pacific dogfish spine recorded at beamlines 8-BM and 2-ID-E, APS; of particular note are bands of high Zn content, something which has been found in growth bands in other mineralized tissues.
KEYWORDS: Data acquisition, Tomography, Sensors, Visualization, Synchrotrons, Reconstruction algorithms, Real time imaging, Microscopes, Dimensional metrology, Data processing
Tomographic experiments at modern synchrotrons require software and hardware solutions for automatic selecting representative features for high-resolution scanning, real-time feedback on the sample motion and changes of the internal structure, as well as on-demand data saving mechanisms to reduce projection volumes from fast detectors. Here we present a new real-time imaging monitoring instrument allowing for automatic 3D zooming to features of interest, optimized organization of data flow significantly reducing acquired data sizes, and real-time sample reconstruction and visualization. Efficacy of the instrument was demonstrated during several tomographic experiments at beamline 2-BM of the Advanced Photon Source at Argonne National Laboratory.
Applications of X-ray computed tomography (CT) for porosity characterization of engineering materials often
involve an extended data analysis workflow that includes CT reconstruction of raw projection data, binarization, labeling and mesh extraction. It is often desirable to map the porosity in larger samples but the computational challenge of reducing gigabytes of raw data to porosity information poses a critical bottleneck. In this work, we describe algorithms and implementation of an end-to-end porosity mapping code "Tomo2Mesh" that processes raw projection data from a synchrotron CT instrument into a porosity measurement and visualization within minutes on a single high-performance workstation equipped with GPU.
As X-ray imaging is pushed further into the nanoscale, the sample deformations due to the increased radiation levels or mechanical instabilities of the microscopes become more apparent, leading to challenges in realizing high-resolution microscopy under these conditions. Here we propose a distributed optimization solver for imaging of samples at the nanoscale. Our approach solves the tomography and ptychography problems jointly with projection data alignment, nonrigid sample deformation correction, and regularization. Applicability of the method is demonstrated on experimental data sets from the Transmission X-ray Microscope, and the hard X-ray nanoprobe.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.