Visualization and measurement of concentration and surface range images

Abstract

Images representing the variation in elemental concentration or some intensity signal proportional to it, are produced by instruments such as the electron and ion microscope. They are customarily presented as “dot” maps in which the density of dots represents the concentration, or if the counting statistics of the signal are adequate, as a continuous tone grey scale image. Range images in which the elevation of a surface is recorded as an array of values which can be displayed as a grey-scale image, are produced by several instruments, including the scanning tunneling microscope, atomic force microscope, interferometric light microscope, and the confocal scanning light microscope. Display of the resulting concentration or elevation data with false color to enhance the visibility of small differences, or with expansion or compression of the vertical scale, or subtraction of a reference surface such as a best-fit plane, are often included. Some instruments offer additional display modes such as line profiles, along with some numerical data, such as the mean, standard deviation and limits of the values.