An X-ray diamond focuser based on an array of three-component elements

The use of a compound refractive lens fabricated of a thin diamond plate is considered for focusing hard 9.25 keV X-rays. Each element of the diamond lens consists of a central cavity and two side cavities in the diamond plate. It is shown numerically that an array of 20 such elements is able to produce a focal spot of width FWHM = 57 nm. The lens aperture size is 30 µm and the diamond plate thickness is 2 mkm. The simulation shows that by proportionally increasing the dimensions of the lenses on all three axes, bringing the input pupil size to 1 µm, the X-ray focal spot width can be increased to 1 µm using the same lens array.