Two-dimensional x-ray magnification based on a monolithic beam conditioner

In x-ray imaging and beam conditioning it is useful to magnify or demagnify the x-ray beam, or an image, approaching (sub)micrometre resolution or the (sub)micrometre illuminated region. Using an asymmetric diffractor it is possible to expand or compress the x-ray beam in one direction. Combining two such diffractors with mutually perpendicular planes of diffraction even two-dimensional beam expansion or compression can be obtained and, for suitable wavelengths, it is even possible to design and cut a single crystal in such a way that it works as a monolithic device expanding or compressing the x-ray beam in two directions. In this paper, a new magnifying monolithic optical device for a two-dimensional magnification of 25 at 10 keV, based on two noncoplanar asymmetrically inclined {311} diffractors, was designed and made from a single silicon crystal. A ray-tracing image has been simulated to check the functionality of the device. The experimental testing of this device was performed at Optics beamline BM5 at ESRF Grenoble. An undistorted image magnification of about 15 was achieved at a photon beam energy of 9.6 keV. When the photon energy was increased, a higher magnification and increased distortion were observed (horizontal magnification of 39, vertical magnification of 20) at an energy of 10.045 keV. The advantages and disadvantages of the device, as well as further steps to improve it are briefly discussed.