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The X-ray Kirkpatrick-Baez (KB) imaging experiment with single layer is implemented. Based on the astigmatism aberration and residual geometric aberration of a single mirror, a KB system with 16 × mean magnification and approximately 0.45 o grazing incidence angle is designed. The mirrors are deposited with an Ir layer of 20-nm thickness. Au grids backlit by X-ray tube of 8 keV are imaged via the KB system on scintillator charge-coupled device (CCD). In the ±80 µm field, resolutions of less than 5 µm are measured. The result is in good agreement with the simulated imaging.

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This paper presents a novel lobster-eye imaging system for X-ray-backscattering inspection. The system was designed by modifying the Schmidt geometry into a treble-lens structure in order to reduce the resolution difference between the vertical and horizontal directions, as indicated by ray-tracing simulations. The lobster-eye X-ray imaging system is capable of operating over a wide range of photon energies up to 100 keV. In addition, the optics of the lobster-eye X-ray imaging system was tested to verify that they meet the requirements. X-ray-backscattering imaging experiments were performed in which T-shaped polymethyl-methacrylate objects were imaged by the lobster-eye X-ray imaging system based on both the double-lens and treble-lens Schmidt objectives. The results show similar resolution of the treble-lens Schmidt objective in both the vertical and horizontal directions. Moreover, imaging experiments were performed using a second treble-lens Schmidt objective with higher resolution. The results show that for a field of view of over 200 mm and with a 500 mm object distance, this lobster-eye X-ray imaging system based on a treble-lens Schmidt objective offers a spatial resolution of approximately 3 mm.

An auxiliary visible imaging method was introduced to solve the axial and pointing alignment of x-ray Kirkpatrick-Baez optics. Through ZEMAX simulation and x-ray imaging experiments, the axial and pointing alignment accuracy were determined to be ±300μm and ±20μm respectively. The numerical aperture of x-ray Kirkpatrick-Baez optics is rather small, so it's impossible to adjust Kirkpatrick-Baez system by visible imaging directly. An auxiliary visible lens was designed, which was equivalent to x-ray Kirkpatrick-Baez optics on conjugate relationship and accuracy control. The comparative experiments of visible imaging and x-ray imaging indicate that this auxiliary system could meet the alignment accuracy of Kirkpatrick-Baez optics.