Crystal monochromator

Neutron monochromator for the ECHIDNA powder diffractometer at OPAL in Australia. It is made by slabs of [113] oriented Germanium crystals which are inclined towards each other in order to focus down the Bragg reflected beam.

A crystal monochromator is a device in neutron and X-ray optics to select a defined wavelength of the radiation for further purpose on a dedicated instrument or beamline. It operates through the diffraction process according to Bragg's law.

Similar devices are called crystal analyzer for the examination of scattered radiation.