Abstract: A particle beam column for high-resolution imaging and measurement of topographic and material features on a specimen. The particle beam column includes a particle source for providing a primary beam along a primary beam axis for impinging on the specimen so as to release secondary electrons and backscattered electrons therefrom. The particle beam column also includes an objective lens for focussing the electrons so as to provide a radial dispersion of electrons relative to the primary beam axis, the radial dispersion of electrons including an inner annulus of backscattered electrons and an outer annulus of secondary electrons. The particle beam column still further includes a backscattered electron detector for detecting the inner annulus of backscattered electrons and a secondary electron detector for detecting the outer annulus of secondary electrons.