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The technique of computed tomography (CT) has been used in various fields, such as medical, non-destructive testing (NDT), baggage checking, etc. A 3D-CT system based on the portable synchrotron “MIRRORCLE”-series will be a novel instrument for these fields. The hard x-rays generated from the “MIRRORCLE” have a wide energy spectrum. Light and thin materials create absorption and refraction contrast in x-ray images by the lower energy component (< 60 keV), and heavy and thick materials create absorption contrast by the higher energy component. In addition, images with higher resolutions can be obtained using “MIRRORCLE” with a small source size of micron order. Thus, high resolution 3D-CT images of specimens containing both light and heavy materials can be obtained using “MIRRORCLE” and a 2D-detector with a wide dynamic range. In this paper, the development and output of a 3D-CT system using the “MIRRORCLE-6X” and a flat panel detector are reported. A 3D image of a piece of concrete was obtained. The detector was a flat panel detector (VARIAN, PAXSCAN2520) with 254 μm pixel size. The object and the detector were set at 50 cm and 250 cm respectively from the x-ray source, so that the magnification was 5x. The x-ray source was a 50 μm Pt rod. The rotation stage and the detector were remote-controlled using a computer, which was originally created using LabView and Visual Basic software. The exposure time was about 20 minutes. The reconstruction calculation was based on the Feldkamp algorithm, and the pixel size was 50 μm. We could observe sub-mm holes and density differences in the object. Thus, the “MIRRORCLE-CV” with 1MeV electron energy, which has same x-ray generation principles, will be an excellent x-ray source for medical diagnostics and NDT. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The portable synchrotron “MIRRORCLE-6X” provides hard x-rays with high brightness and wide energy spectrum ranging from 10–300 keV, emitted from a micron-sized source, with wide divergence of ± 85 mrad. Correspondingly, images obtained using the “MIRRORCLE-6X” showed significantly improved characteristics compared to conventional x-ray tube images, namely, improved refraction contrast, high resolution, and high magnification. Thus, the “MIRRORCLE-6X” is considered to be a novel medical imaging source. A magnified image of a chest phantom, wherein a urethane ball of 8 mm diameter was implanted as an imitation of a cancer, was obtained. The detector used was an imaging-plate (Fujifilm imaging plate, FCR ST-IV) with 150 μm pixel size. The phantom and the detector were respectively set at 50 cm and 540 cm from the x-ray source, so that the magnification was 10.8x. The x-ray source was a Cu 25 μm rod. The resolution was about 25 μm. Images with such high resolution and magnification cannot be obtained by conventional x-ray tubes with a source size of mm order. We can see the edges of costae and of the urethane ball at the back of the costae by the refraction contrast effect. Furthermore, we also see blood vessels surrounding the urethane ball. White spots, which are cross sections of blood vessels, were also observed. Therefore, observations of the shape of a cancer without surgical resection should be possible, and accurate diagnosis can be given using the “MIRRORCLE-6X”. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

The portable synchrotron MERRORCLE-6X is a novel x-ray source suitable for hard x-ray imaging. Highly brilliant x-rays are generated by MIRRORCLE-6X in the shape of cone from a source with micron size. We obtained images with high magnification and high resolution by these x-rays, and found that they can be utilized for medical imaging. Recently, we started to perform ideal 3-dimentional computed tomography (3D-CT) based on the Feldkamp algorithm, which is the most popular reconstruction algorithm for a cone beam CT, using a flat panel detector. Therefore, we developed a magnified 3D-CT system of high quality using MIRRORCLE-6X. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

A Protein crystallography beam line using MIRRORCLE-6X, which is a compact synchrotron for hard x-ray production, is under construction. Since MIRRORCLE-6X provides hard x-ray with high brightness, it is suitable for x-ray source of accurate protein crystallography research in a small laboratory. The divergent x-ray emitted from a target is focused by a condensing minor. The minors used for the condensing minor are a multi layer minor of Wolter type and a rotating ellipsoidal minor. Photon energies dispersed by them are set to the K-edge of Zn and of Se, respectively. The flux at a focusing point is expected to be 10³ ∼ 104 times larger than that without the condensing minor. The focusing size is less than 100 μm of diameter. The x-ray after the minor is transformed to parallel beam using a Fresnel zone plate and irradiated on a protein crystal. The diffraction figure is detected by the an imaging-plate detector. [ABSTRACT FROM AUTHOR]

Monochromatic x-ray CT at two different energies provides information about electron density without ambiguity due to the beam hardening effect. This information makes the treatment planning for heavy-ion radiotherapy more precise. We have started a feasibility study on the dual-energy x-ray CT by using synchrotron radiation. We developed a linear scanning CT system in order to evaluate what precision in the measurement was achieved. The experiments were carried out using monochromatic x-rays of 40, 70 and 80 key. Comparison of measured electron densities with the theoretical values proved that these values were in agreement in 0.9 % on average. We have developed a 2D-CT system with a two-dimensional scintillator array to take images in a short time. At present, it has been proved that the electron density is measured in the precision of about 1% with the 2D-CT system. Effective atomic numbers are obtained as well from the dual-energy x-ray CT. The CT images are reconstructed based on each of the electron density and the effective atomic number. They present different features of an object, and the contrasts in the images differ from that in a conventional CT image. The feature of the images may help distinguish more clearly tissues or organs with aid of different contrast from the conventional CT images. [ABSTRACT FROM AUTHOR]

A laboratory-scale hard X-ray microscope utilizing the portable synchrotron named MIRRORCLE-6X is developed in our laboratory. MIRRORCLE-6X is a X-ray source suitable for hard X-ray microscopy as a result of the X-ray source size of the order of micron, and highly brilliant hard X-rays. Furthermore, when effective focusing elements of hard X-rays are used for MIRRORCLE-6X, this machine could be used for non destructive inspection with high resolution of biological and engineering. We designed hard X-ray optical elements for MIRRORCLE6X and started fabricating X-ray mirrors. [ABSTRACT FROM AUTHOR]

Brilliant hard X-rays are produced by the portable synchrotron named MIRRORCLE. The X-ray images taken by MIRRORCLE show enhanced edge effect even with contact imaging. Bodies composed of soft tissues are distinguished in spite of the predominantly hard X-ray components. The imaging mechanism, which is different from the phase contrast, was studied. It was found that the edge effect is partly due to the micron order x-ray source spot size, and MeV region hard X-rays. The characteristic of the medical diagnosis X-ray images and nondestructive inspection X-ray images taken by MIRRORCLE are studied in this paper. [ABSTRACT FROM AUTHOR]