The first XRF spectrometers were built following the achievements in construction of goniometers for X-ray diffractometers. Radiation from the x-ray tube is passed through Soller collimators as to shape a parallel beam impinging to the sample surface. Further, parallel characteristic x-rays emitted by the sample reach a monochromator device that is tilted within an interval of angles as to separate the x-rays by wavelength before they reach the detector. The wavelength resolution of the diffracting device makes possible to obtain a wavelength resolution that surpasses that attained by EDXRF spectrometers.

WDXRF require of periodic verification of the alignment of tis components. The improvements in technology have made possible to operate quite robust instruments.

The instrument available at NSIL has the following characteristics: