High energy X-ray transfocator based on Al parabolic refractive lenses for focusing and collimation

Abstract

We describe an X-ray transfocator – a lens assembly whose focal length can be continuously adjusted by the mechanical movement of one or more groups of individual lenses. The transfocator consists of 7 cylindrical cartridges containing 2, 4, 8, 16, 32, 64 and 128 Al parabolic lenses respectively. Pneumatic actuators are used to bring cartridges in and out of the beam independently providing collimation or focusing at a desired distance downstream. The transfocator is installed in the ID11 extension beamline at 90 m from the source. The tests were performed at the energy range between 25 and 60 keV X-ray energy.