A.E.Hughes
Cambridge University Press
Fast Hyperspectral Soft X-Ray Mapping
Introduction
X-ray mapping is an important tool for non-destructively assessing the chemical composition of solid samples. With the recent development in both computational technology and detector technology, hyperspectral x-ray maps can now be used to further analysis.
Soft x-ray emission spectrometers are one of the most recent hyperspectral detectors, and can measure very low energy x-rays, increasing chemical analysis through the use of direct lithium measurements and spectral mapping of L, M, and N lines of certain elements.
Typically, these spectrometers utilize a 2048 x 2048, x-ray sensitive CCD camera for measurement. However, CCDs of this size are limited by the amount of time taken to readout a spectrum, even with on-chip binning.
Researchers from Australia attached a SOPHIA-XO onto a soft x-ray emission spectrometer, alongside other detector types, to optimize the experimental configuration of x-ray hyperspectral mapping. With the four-port readout of the SOPHIA-XO, the researchers were able to achieve readout speeds 10x faster than that of traditional CCD cameras. The researchers were concerned that the faster readout would result in a lower signal-to-noise ratio, due to the reduction of signal accumulation. However, the improved electronics of the SOPHIA-XO improved the noise characteristics, increasing the signal-to-noise ratio in comparison to other models.
