Confocal micro X-ray fluorescence analysis

In confocal micro X-ray fluorescence (micro XRF) analysis a primary X-ray beam (e.g. from an X-ray tube or from an accelerator) is focused with an X-ray optics. The primary beam – pictured in yellow in the video – is focused with a polycapillary half lense.  The area seen by the detector is defined by a second X-ray optics (e.g. a second polycapillary half lense). The detector is represented by a gray cube in the video. The area it could detect is shown as a blue beam. The overlap of the focal spots of the exiting beam (yellow) and the area the detector could observe (blue) defines the actual detection volume (green square). Only fluorescence radiation from this volume is detected by the detector. By moving the sample through this detection volume the sample can be scanned in 3D voxel by voxel. Furthermore, the confocal setup eliminates fluorescence radiation (especially of high Z elements) of deeper layers and, therefore, improves the spacial resolution.

Creative Commons License
The confocal micro XRF setup video by M. Rauwolf is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.