Improvement of spatial resolution in 2D and 3D x-ray fluorescence analysis

Complete text of publication follows. We can use a polycapillary lens or a single capillary lens to obtain a strong x-ray micro beam in the laboratory. We have attempted to obtain the strong micro x-ray beam by combining the polycapillary lens with the tungsten conical pinhole. The beam diameter of x-ray micro beam was evaluated by a knife edge method. Evaluated beam size (FWHM value) was about 6.0 μm, which roughly corresponded to the diameter of the pinhole. We also investigated the divergence angle of the x-ray beam. The divergence was estimated to be about 11 mrad, which was smaller than the typical divergence of the polycapillary. We can obtain 2D-XRF image by scanning the sample. The spatial resolution is improved by using the x-ray micro beam having a small diameter. We also confirmed that the spatial resolution is improved by applying a metallic filter between the x-ray source and the sample. This is because high energy x-rays give small spot size of the x-ray beam in the case of polycapillary x-ray lens. 3D-XRF image is obtained by using a confocal setup. We will present the result showing that the spatial resolution in 3D-XRF analysis is also improved by adjusting the experimental configuration.