Y. Kohmura et al., X-ray focusing test and x-ray imaging test by a microcapillary x-ray lens at an undulator beamline, REV SCI INS, 70(11), 1999, pp. 4161-4167
A first focusing test of the undulator radiation at SPring-8 has been done
using two types of x-ray refractive lenses in thin glass capillaries. One (
lens No. 1) contained bubbles in a glue whereas the other (lens No. 2) cont
ained bubbles in glycerol. The capillaries had inner diameters of 0.2 and 0
.8 mm, respectively. Using x rays of 17-18 keV, the undulator source image
was investigated at the focal plane. The spherical aberrations and the fiel
d distortions were carefully examined by taking the images of a gold mesh.
Lens No. 1 had an advantage of high transmissivity in the hard x-ray region
(18% at 18 keV) and high tolerance to severe radiation damage, e.g., simil
ar to 5 x 10(12) photons/s/0.03 mm(2) of the 18 keV x rays for an exposure
time of 1 h. On the other hand, lens No. 2 had an advantage of a large aper
ture, 0.8 mm, and a small field distortion, e.g., less than 10% inside a di
ameter of 300 mu m. (C) 1999 American Institute of Physics. [S0034-6748(99)
05011-X].