Saving the photons: mapping X-rays by position-tagged spectrometry.

Since the early years of X-ray spectrometry in electron microscopes, mapping the locations of chemical elements has been important. The X-rays needed in large numbers for this are rare, owing to poor production efficiency compared with electron signals, and at risk of loss by many mechanisms such as missing the limited solid angle of the detector, absorption before reaching the detector and pulse pile-up conventional digital mapping hardware reduces the information contained in the X-ray spectrum at each pixel to the itegrated counts from a few regions of interest.The acquisition technique of position-tagged spectrometry eliminates the conflict between the desire to see full frame X-ray images quickly versus the analytical advantages of having complete spectra for each pixel.

Energy-Dispersive Spectrometry from Then until Now: A Chronology of Innovation.

: As part of the Microbeam Analysis Society (MAS) symposium marking 30 years of energy-dispersive spectrometry (EDS), this article reviews many innovations in the field over those years. Innovations that added a capability previously not available to the microanalyst are chosen for further description. Included are innovations in both X-ray microanalysis and digital imaging using the EDS analyzer.