Schematic of the main parts of a Talbot-Lau interferometer. Gratings are labeled as follows: g0 the “source” grating, g1 the “phase” or “beam-splitter” grating, and g2 the “analyzer” grating.
(a) Moiré pattern image obtained from a beryllium rod and corresponding reference pattern superposed. (b) Density gradient map (gray scale) and superposed line profile (vertically integrated) of the edge of a beryllium rod. Distance refers to the direction perpendicular to the axis of symmetry of the Be cylinder.
Refraction angle profiles obtained with system angular width of 80 μm, magnification of 11 and talbot order of 3, produced by (a) a beryllium rod and (b) an aluminum rod. A section of each rod was probed as illustrated in Figure 2(a) .
XWFP comparison of Moiré refraction method and propagation method. The top curve shows the intensity measured along the Be rod without the gratings in the beam (propagation effects), and the bottom curve shows the value of the fringe shift obtained through TL Moiré method.
Experimental, synthetic, and theoretical: (a) Refraction angles and (b) attenuation for Be, Al, and Na cylindrical rods, measured perpendicular to the line gratings. The attenuation curves are vertically shifted, with constant value regions representing unity attenuation.
Simulated Moiré images of a beryllium rod, probed as shown in Figure 2(a) , using an x-ray source of (a) 80 μm, (b) 40 μm, and (c) 10 μm spot sizes.
(a) Interferometer contrast versus Talbot order, with fringe period of ∼100 μm. (b) Interferometer contrast versus fringe period at Talbot order of 3.
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