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arXiv · 2610.17515

Non-contact lens metrology from optical flow and differentiable ray tracing

Hector A. Jimenez-Romero·Wolfgang Heidrich
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Abstract

Accurate lens surface metrology is essential to determine the manufactured geometry of refractive optical elements and their deviation from the specified design. We demonstrate a transmission metrology method that reconstructs refractive lens surfaces from the displacement of a wavelet-noise-patterned mask. Lens-induced distortion is represented by a dense displacement field. A differentiable ray tracer fits the lens geometry using a calibrated near-telecentric camera model with an effective finite ray origin. We validate the method on commercial lenses. The recovered geometries agree with nominal specifications, and the plano-aspheric reconstruction is compared with chromatic confocal profilometry.

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Hector A. Jimenez-Romero, Wolfgang Heidrich. 2026-10-13. Non-contact lens metrology from optical flow and differentiable ray tracing. https://arxiv.org/abs/2610.17515

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