Focusing x‐rays to a 1 μm spot using elastically bent, graded multilayer‐coated mirrors

摘要: In the LBNL x‐ray fluorescence microprobe, a synchrotron source of x‐rays is demagnified several hundred times using pair mirrors in Kirkpatrick‐Baez configuration. These are coated with multilayers to increase reflectivity and limit pass band striking sample. With spherical mirrors, spot size obtained limited by aberration. This can be corrected an initially flat mirror elastically bent combination end couples into ellipse. By grading multilayer coatings d‐spacing, throughput focusing system increased narrowed. A such installed microprobe on bending magnet at Advanced Light Source (ALS), achieved focal spots dimensions 1μm×1 μm energies 8.5 keV 12 keV, energy 10%.