Double Crystal Monochromator
FMB Oxford has unparalleled expertise in customised hard x-ray monochromators, having designed and constructed more than 80 since the first unit was delivered to the ALS in 1996.
The FMB Oxford DCM, the leading monochromator for hard X-ray applications, is a versatile high performance system suitable for use on both bending magnet, wiggler and undulator beamlines. The spectral range required determines the choice of crystals; multiple sets of crystals can be installed, with in-vacuum selection. The system can be used in either fixed offset or pseudo-channel cut mode. We can provide either water-cooling or cryo-cooling for the first crystal, depending on the heat load to be dissipated and the thermal and optical performance required. We offer a range of second crystal designs: short second crystals with parallel translation; long second crystals which allow the beam to walk the length during Bragg rotation; and sagittally bent second crystals for focusing.
The DCM consists of the vacuum system, goniometer, crystal support, and manipulation mechanism, mounted on a substantial synthetic granite block. The associated electronics can be supplied mounted in a 19” rack system.
Specifications
- UHV design and manufacture throughout
- High precision rotary table goniometer for Bragg angle rotation
- Crystal cage mounted on rigid drive shaft for exceptional stability
- Goniometer supported on synthetic granite plinth for superior vibrational damping
- Slide mount for goniometer allowing easy removal when vacuum chamber is open
- Axis of goniometer large enough to accommodate both water and cryogenic feedthroughs
- Crystal cage configurable for vertical offset, with exit beam higher or lower than input beam
- Compact footprint
- Fine pitch and roll controls
Options
- Standard Sagittal bender
- Enhanced Sagittal bender
- Set of Crystals
- Non-standard offset
- Non-standard Bragg Angle range
- Motorised support feet with precision hard stop
- Multiple mounted crystal sets with in vacuum crystal translation
- Multiple mounted crystal sets with in air crystal translation
- Turntable to allow goniometer to rotate once withdrawn from vacuum vessel
- Motorised first crystal roll
- First crystal in vacuum vertical translation
- Controllers for translation motors
- Compton shielding
