A novel, to our knowledge, approach to light-stripe triangulation configuration that allows for parallel, fast, real-time three-dimensional surface topography with an extremely large number of optically resolved depth steps is presented, analyzed, and experimentally demonstrated. The method is based on a color-coding and decoding arrangement that exploits polychromatic illumination and axially dispersing optical elements. This leads to an increase of the depth-measuring range without any decrease in the axial or the lateral resolution. Our experiments yield three-dimensional surface measurements with lateral and depth optical resolutions of <40 nm, for a depth of focus of 48 mm, resulting in 1.2 × 106 resolving depth steps.
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