Compact Multilayer Monochromator
The compact multi-layer monochromator is a versatile high performance system suitable for use on all beamlines; the device is simpler than the advanced MLM and is particularly appropriate for beamlines with limited access e.g. adjacent beamlines.
This MLM is suitable for most hard X-ray applications including Small angle Scattering (SAXS) and Tomography where greater flux throughput is obtained by increasing the bandpass normally obtained from a crystal monochromator. The bandpass is typically about 1-3%. The spectral range is dependent on the choice of multi-layers.
The system has a motorized precision rotation stage for both multi-layers simultaneously, as well as a linear translation for the second multi-layer to follow the diffracted beam. The exit height of the beam does change slightly with energy.
The complete MLM system consists of the vacuum vessel, internal multi‑layer rotation stage with sine arm and external motor/gearbox, water‑cooled first multi-layer support with mask, second multi-layer translation, and support stand. We can offer this design integrated with a CCM in tandem.
Specifications
| General | Vertical offset (4mm) bounce up geometry |
| Vertical beam height acceptance | 1mm typical (depends on energy range required etc.) |
| Vacuum vessel | UHV < 10-9mbar 870mm long. Fitted with external fiducials and supplied with all surveying data |
| Beam height | 1,400mm, or as required |
| Energy range | <1keV to 20keV (depends on multi-layer selected) |
| Incidence angle range and accuracy | 0-10° with <1μrad steps (to give better than 1eV at 12eV) |
| Range/resolution of second multi-layer motion | Motion parallel to multi-layer surface, 120mm tootal range, accuracy <100μm |
| Range/resolution of second multi-layer angles | ±2° / 1μrad pitch ±2° / 1μrad roll |
System based on Peter Siddons’ design in use at the NSLS, Brookhaven.