Cylindrical compound refractive x-ray lenses using plastic substrates

We have measured the intensity profile of x rays focused by compound refrac tive lenses (CRLs) fabricated using acrylic (Lucite) and polyethylene plast ics. A linear array of closely spaced holes acts as multiple cylindrical le nses. The important parameters for this type of focusing are the focal leng th and absorption, and, for wavelengths shorter than 3 Angstrom, low atomic number plastics are suitable. We have experimentally demonstrated that we can achieve one-dimensional focusing for photon energies between 9 and 19.5 keV with focal lengths between 20 and 100 cm. For example, using 12 keV x rays we have achieved focal full width at half maximum linewidths down to 2 1 mu m at a distance of only 20 cm from the CRL. The x-ray source was a syn chrotron emitter whose source size in the vertical dimension was 445 mu m. (C) 1999 American Institute of Physics. [S0034-6748(99)03209-8].