The spread function of a polycapillary lens and a confocal X-ray microscope in retuning its confocal volume

Mercury in archeological hair samples from Xiongnu burials (Noin‐Ula, Mongolia): SR XRF and CXRM analysis

“…Parameters of the CXRM: ‐ channel‐cut Si (111) monochromator; ΔЕ/E = 3÷4 × 10 −4 ;‐ scanning of samples: up to 25.4 mm in 3 coordinates (xyz) with a minimum pitch of 0.1 μm, option of nonstandard angular orientation of sample; ‐ energy range: 6–25 keV;‐ focal spot size (spatial resolution): 300 to 5 μm, ‐ detector Amptek XR 100 SDD, a resolution of about 150 eV on the Fe‐K α line ‐ optical microscope with a magnification of 80. …”

“…Scanning is performed through displacement of the sample in three linear coordinates relative to the confocal volume. The sample is pre‐adjusted with respect to the beam in the three angular coordinates; a goniometer enables rotation in a horizontal plane with a minimum step of 0.002° . The CXRM method was applied to examination of an archeological sample of a hair.…”

Resolving hidden pixels beyond the resolution limit of projection imaging by square aperture

“…tube anode, can be considered as a collection of point sources. While each point acts as an origin of their respectively projected beams through the sample down to the detector, all of them are then superimposed onto each other, to form a blurred image on the detector screen 17 – 22 . Although, in principle, this blurriness could be resolved through the so called “point spread function” (PSF) of the x-ray source, via Fourier transforms and inversion, it has been rather impractical, if not entirely impossible, as the division of the PSF transform, usually of an oscillation function involving many zeros, ruins the operation.…”