High Definition X‐Ray Fluorescence: Principles and Techniques

Abstract

Energy dispersive X-ray fluorescence (EDXRF) is a well-established and powerful tool for nondestructive elemental analysis of virtually any material. It is widely used for environmental, industrial, pharmaceutical, forensic, and scientific research applications to measure the concentration of elemental constituents or contaminants. The fluorescing atoms can be excited by energetic electrons, ions, or photons. A particular EDXRF method, monochromatic microfocus X-ray fluorescence (MμEDXRF), has proven to be remarkably powerful in measurement of trace element concentrations and distributions in a large variety of important medical, environmental, and industrial applications. When used with state-of-the-art doubly curved crystal (DCC) X-ray optics, this technique enables high-sensitivity, compact, low-power, safe, reliable, and rugged analyzers for insitu, online measurements in industrial process, clinical, and field settings. This new optic-enabled MμEDXRF technique, called high definition X-ray fluorescence (HD XRF), is described in this paper.

X-ray fluorescence imaging with the Medipix2 single-photon counting detector

“…Let the Silicon sensor be divided into layers and assume that the spread of the charge is limited to an area of 3 3 pixels. This assumption is appropriate because the observed cluster size for the anticipated energy range ( to keV) was less than 3 pixels [12] for the applied bias of 100 V. For -th layer we calculate convolution: (2) where:…”

Energy resolved X-ray fluorescence imaging based on a micropattern gas detector

“…Nowadays, this technique allows important applications in areas as biology and biomedicine, art history, and industry, among others. Different XRFI systems commonly used are based either on scanning systems, like a Scanning Electron Microscope or a microfocus X-ray system combined with an Energy Dispersive Spectrometer [1], or on full field of view systems based on Charge Coupled Devices (CCDs) or on Medipix 2 [2,3]. The first ones have high position and energy resolution, but need sample preparation and have the limitation of the sample size, presenting in addition the limitations inherent to the scanning systems, i.e.…”

Measurement of the microdistribution of strontium and lead in bone via benchtop monochromatic microbeam X-ray fluorescence with a low power source

“…10,11 The system has demonstrated maximum detection limits at femtogram levels, and spatial resolutions better than 100 µm, for 2 µL droplets placed on silicon wafers; it thereby provides a significant improvement in performance over other benchtop X-ray fluorescence systems with. The improved performance results from the use of a doubly curved crystal optic (DCC) (X-ray Optical Systems (XOS) Inc, East Greenbush, NY) to focus the X-rays, and thus increase the usable flux (1×10 9 photons/s) from a standard laboratory source.…”