Coherent high energy X-ray microscope was employed to study the wide range of natural and artificial mesoscopic materials that are structured on scales of the order of a few to a few hundred nanometers. The microscope operates under a coherent illumination where a diffraction pattern of the specimen is formed in the back focal plane of the condenser and an inverted two-dimensional image of the object is formed by objective lens in the image plane. Functioning at 10 – 30 keV, the microscope consists of the condenser, the objective lens and two X-ray CCD cameras – large area detector for diffraction and high resolution CCD for imaging. Condenser and objective assemblies are comprised of Be parabolic refractive lenses. Switching from the diffraction mode to the imaging is achieved by placing the objective lens into the beam, and the chosen detector. The tunable objective lens offers full-field imaging with variable resolution and field of view.
The microscope was applied for study of natural and synthetic opals, metal inverted photonic crystals and colloidal suspensions. The combination of the direct-space imaging and high resolution diffraction provide a wealth of information on their local structure and the long range periodic order. The development of the hard x-ray microscope emerged concomitantly with the realization of the ESRF source upgrade which greatly enhanced brilliance and fraction of coherent light, and this will open entirely new frontiers in materials imaging.
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