The  optical scheme of ID24-ED  consists of a pair of mirrors (MV1 and MH1) in a Kirkpatrick Baez configuration, and of a polychromator (elliptically curved crystal) in Bragg or Laue geometry. The role of the MH1 is to create a secondary source and transform the highly collimated undulator beam into a diverging beam in the horizontal plane, to provide a large footprint on the crystal and therefore a large energy range in the polychromatic fan to enable EXAFS. The X-ray beam is focused by the polychromator at the sample position and re-dispersed on a position sensitive detector, placed at the end of the 2Θ spectrometer arm, that converts energy (X-ray direction) into position (detector pixel).

 

 

With this scheme a beam of 5-80 microns in horizontal (energy dependent) and 70 microns in vertical can be obtained on the sample . It is possible to add a second vertical mirror (VRM) to also focus the beam in vertical down to few microns.