Characterization of a confocal three-dimensional micro X-ray fluorescence facility based on polycapillary X-ray optics and Kirkpatrick–Baez mirrors

A new confocal three-dimensional micro X-ray fluorescence (3D micro-XRF) facility based on polycapillary X-ray optics in the detection channel and Kirkpatrick–Baez (KB) mirrors in the excitation channel is designed. The lateral resolution (lx, ly) of this confocal three-dimensional micro-X-ray fluorescence facility is 76.3(lx) and 53.4(ly) µm respectively, and its depth resolution dz is 77.1 μm at θ = 90°. A plant sample (twig of B. microphylla) and airborne particles are analyzed.