For many applications there is a requirement for nondestructive analytical investigation of the elemental distribution in a sample. With the improvement of X-ray optics and spectroscopic X-ray imagers, full field X-ray fluorescence (FF-XRF) methods are feasible. A new device for high-resolution X-ray imaging, an energy and spatial resolving X-ray camera, is presented. The basic idea behind this so-called "color X-ray camera" (CXC) is to combine an energy dispersive array detector for X-rays, in this case a pnCCD, with polycapillary optics. Imaging is achieved using multiframe recording of the energy and the point of impact of single photons. The camera was tested using a laboratory 30 μm microfocus X-ray tube and synchrotron radiation from BESSY II at the BAMline facility. These experiments demonstrate the suitability of the camera for X-ray fluorescence analytics. The camera simultaneously records 69,696 spectra with an energy resolution of 152 eV for manganese K(α) with a spatial resolution of 50 μm over an imaging area of 12.7 × 12.7 mm(2). It is sensitive to photons in the energy region between 3 and 40 keV, limited by a 50 μm beryllium window, and the sensitive thickness of 450 μm of the chip. Online preview of the sample is possible as the software updates the sums of the counts for certain energy channel ranges during the measurement and displays 2-D false-color maps as well as spectra of selected regions. The complete data cube of 264 × 264 spectra is saved for further qualitative and quantitative processing.

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A portable focused‐beam X‐ray fluorescence (XRF) spectrometer was designed and manufactured taking into account a huge variation in material, size and shape of museum objects. The spectrometer is equipped with a vacuum chamber enclosed with a Kapton‐window allowing the detection of chemical elements from Na upwards, which enables the characterization of glass and enamel objects. Two low‐power X‐ray tubes, one with a Mo‐anode the other with a Cr‐anode, operating from 4 to 50 kV and 0 to 2.5 mA with a maximum power of 50 W and a point focus of about 180 µm can be used as excitation source alternatively. A polycapillary lens with a spot size of 150 µm is used for focusing the primary beam to access small details of the different objects, e.g. fine brush strokes in paintings. The vacuum chamber can be evacuated to about 1 mbar.A miniature camera is installed inside the chamber for inspecting the analyzed area through the Kapton‐window. Two laser pointers mounted inside the chamber coincide with the focal point of the polycapillary at the investigated spot. The excitation and X‐ray fluorescence radiation paths in air are about 1 mm each, minimizing the absorption losses. The spectrometer was designed to maximize the accessibility to all parts of the investigated objects through the use of translation stages and an innovative design of the detection head, especially the vacuum chamber. This article shows the capability of the spectrometer to reach measuring positions in concave parts of objects and presents the determined detection limits of elements. Copyright © 2009 John Wiley & Sons, Ltd.

X‐ray fluorescence analysis (XRF) is a powerful tool for nondestructive analysis of chemical elements present in art and archeological material. Nevertheless, investigations of objects possessing a glassy matrix still offer some problems using XRF because of the absorption in air of the low‐energy characteristic fluorescence radiation of light elements. With the design of a XRF instrument equipped with a vacuum chamber housing both, the x‐ray optics and the detector snout inside, a new attempt to solve this problem was made. The Conservation Science Department of the Kunsthistorisches Museum Vienna (KHM) had the opportunity to test this instrument on different objects of art. An overview of some results from these measurements, together with a short discussion of the experiences gained during the investigations, is presented in this article. Copyright © 2008 John Wiley & Sons, Ltd.

The measurement of thin slices with a color X-ray camera allows the 3D reconstruction of elemental distributions with X-ray fluorescence.