Precise 3D characterization of engineering surfaces requires non-contact methods that overcome the limitations of conventional microscopy. In this master's thesis, we developed and optimised a modular confocal laser scanning microscope operating in reflectance mode. The chosen methodology is based on an optical design using a 658 nm wavelength laser source, polarisation optics to filter parasitic reflections, and an optical fibre serving as the confocal pinhole. Control of the galvanometer mirrors and the motorised z-axis was implemented via a custom communication protocol using a microcontroller. Experimental validation on an aluminium sample confirmed the system's suitability for topography reconstruction. We achieved a lateral resolution of 1.23 μm and an axial resolution of 26.0 μm. A reference measurement of the step height using a Keyence VHX-7000 digital microscope yielded an actual height of 45.57 ± 3.06 μm. Using 3D Gaussian filtering, we measured a height of 44.89 μm (error -1.5 %) for a single cross-section, while statistical analysis of all cross-sections yielded a median of 45.00 μm (error -1.3 %). The developed system thus achieves a relative accuracy better than 2 % for height differences of approximately 50 μm. With this system, we successfully demonstrated the principle of optical sectioning and profilometry of metal surfaces.
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