The simplest type of a capillary optics is the X-ray guide, a cylindrically shaped monocapillary. It collimates the X-ray beam and limits the divergence angle at the monocapillary exit to the critical angle of total reflection. In comparison to a pinhole an X-ray guide enhances the intensity on the sample surface considerably. X-ray guides are manufactured with different capillary diameters and capillary lengths in accordance with their application. Additionally they can be equipped by aligned pinholes.
| Source – entrance distance f1 [mm] | > 10 |
| Capillary diameter d1* [µm] | 10 ... 1000 |
| Length l** [mm] | 94, 135, 165, 173, 191, 210, 230 |
| Energy range [keV] | 1 ... 30 |
| Optimal source size [mm] | 0.02 ... 1.0 |
| Housing diameter dmax*** [mm] | 7, 10, 16 |
| Intensity gain | 3 ... 10 |
