Simplification of alternating least squares solutions with contrast enhancement

A problem with self-modeling mixture analysis solutions is the range of solutions that is generally possible. The range of solutions goes from those with high contrast spectra and low contrast contributions/images to solutions with high contrast contributions/images and low contrast spectra. The term contrast is a measure for dissimilarity, which results in simpler spectra or images. Because of their simplicity, the extremes of this solution range often have clear advantages for the interpretation of the data. Previously, an angle modification in alternating least squares self-modeling mixture analysis has been shown as a method of identifying these extremes. The utility of this method of this utility will be demonstrated in this paper with : autofluorescence spectroscopy microscopy images of lung cells; secondary ion mass spectrometry (SIMS) analysis of a sample obtained by laser activation modification of semiconductor surfaces (LAMSS) and energy dispersive X-ray fluorescence (EDXRF) of a granite sample.