High-throughput real-time x-ray microtomography at the Advanced Photon Source

It is now possible for large volumes of synchrotron- radiation-generated micro-tomography data to be produced at gigabyte-per-minute rates, especially when using currently available CCD cameras at a high-brightness source, such as the Advanced Photon Source (APS). Recent improvements in the speed of our detectors and stages, combined with increased photon flux supplied by a newly installed double multilayer monochromator, allow us to achieve these data rates on a bending magnet beamline. Previously, most x-ray microtomography experiments have produced data at comparatively lower rates, and often the data were analyzed after the experiment. The time needed to generate complete data sets meant putting off analysis to the completion of a run, thus preventing the user from evaluating the usefulness of a data set and consequently impairing decision making during data acquisition as to how to proceed. Thus, the ability to provide to a tomography user a fully reconstructed data set in few minutes is one of the major problems to be solved when dealing with high-throughput x- ray tomography. This is due to the complexity of the data analysis that involves data preprocessing, sinogram generation, 3D reconstruction, and rendering. At the APS, we have developed systems and techniques to address this issue. We present a method that uses a cluster-based, parallel- computing system based on the Message Passing Interface (MPI) standard. Among the advantages of this approach are the portability, ease-of-use, and low cost of the system. The combination of high-speed, online analysis with high- throughput acquisition allows us to acquire and reconstruct a 512x512x512-voxel sample with a few microns resolution in less than ten minutes.