Comparison of wavelength dispersive X-ray fluorescence and energy dispersive X-ray fluorescence techniques

The wavelength-dispersive fluorescence technique (Primini red lines below) has superior resolution and sensitivity, when compared to the alternative energy-dispersive fluorescence method ("EDX" blue lines below). For example, figure below displays the resolving power of the wavelength technique in the area of the titanium (Ti-KA) and barium (Ba-LA) overlap with two distinct peaks, distinguishing it from the amorphous scatter seen in the energy peak at the same region. 

The increased sensitivity in determining trace level elemental content from the background noise with the wavelength technique is further exemplified in the figure below, where fluorine (F-KA), iron (Fe-LA), and sodium (Na-KA) peaks are all detected in the wavelength scan, but entirely lost to the background in the energy scan.