Development of a high-precision slit for x-ray beamline at SPring-8

A high-precision slit for monochromatic x-rays has been developed as one of the standardized components in the undulator beamline at SPring-8. Advanced experiments such as x-ray micro-beam diffraction and x-ray scanning microscope using nano-beam require small, variable and accurate apertures. The newly developed slit has an aperture size ranging from 1 μm × 1 μm to 20 mm × 20 mm with a resolution of 0.5 μm in full step. Each blade is independently driven through bellows mounted on both sides of the vacuum chamber. A set of bellows prevents displacement of the blade by evacuation. Using this slit, we could improve the displacement from 20 μm to 1 μm. The positioning accuracy of the slit is 0.5 μm. The slits have been installed in the three beamlines at SPring-8.