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arXiv · 2504.09659

3D in-situ profiling in a laser micromachining station using dual-comb LiDAR

Hayk Soghomonyan·Justinas Pupeikis·Benjamin Willenberg·Armin Stumpp·Lukas Lang·Christopher R. Phillips·Bojan Resan·Ursula Keller
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Abstract

One of the main challenges in laser micromachining is the complexity of the process development. The available monitoring capabilities are mostly limited to external measurement systems, significantly slowing down this step. We address this limitation by integrating a coaxial dual-comb LiDAR system directly into a laser micromachining station, enabling in-situ, non-destructive 3D profiling without removing the workpiece. The sub-micron raw axial precision of the system, the operation without mechanical delay scanning and a large working range make the system well-suited for profiling a large variety of micromachined structures. By providing in-situ feedback this approach will significantly accelerate laser micromachining process development.

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Hayk Soghomonyan, Justinas Pupeikis, Benjamin Willenberg, Armin Stumpp, Lukas Lang, Christopher R. Phillips, Bojan Resan, Ursula Keller. 2025-04-13. 3D in-situ profiling in a laser micromachining station using dual-comb LiDAR. https://doi.org/10.1364/optcon.572873

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