Evaluation of the measurement performance of a coherence scanning microscope using roughness specimens

Precision manufacturing has seen a steady increase in the use of high-speed, non-contact optical measurements of form and roughness. A dominant technology is coherence scanning interferometry (CSI), also known as scanning white light interferometry (SWLI), which provides quantitative maps of the surface topography for a million image points in a few seconds (Figure 1). CSI relies on interference fringe contrast, optionally combined with interference phase, to determine surface heights [1].