The Nonius Econ Goniometer Head

The MACH3 system consists of a four circle goniometer (Omega, Kappa, Phi to position the crystal and Theta to position the detector) and an X-ray source. The detector measures X-rays diffracted from a crystal.

X-rays can be generated by a sealed tube which is part of the goniometer and a HV generator or by a stand alone rotating anode generator. The X-ray optics consists of a ß filter or a monochromator to suppress the ß- and brehms radiation and a collimator to get a small beam. Safety switches close the shutter or switch off the high voltage in unsafe conditions. In case of a rotating anode generator the shutter and some safeties are handled by the generator. The optics at the detector side consists of a collimator, replaceable slits, a dial unit with computer selectable slits and an attenuator to attenuate high intensities.

The axes are decoded by precision optical encoders and are driven by DC motors, that permit accurate, fast and smooth positioning with low power consumption. The goniometer is driven by an electronic interface, which has a processor, drivers and detector circuit. The system is run by software through the main program on the computer. A selected number of functions, which are needed in the vicinity of the goniometer, can be executed by a pocket terminal. The goniometer is surrounded by a radiation enclosure, which prevents scattering of radiation into the room.