Spatial Calibration of Diffuse LiDARs

Nikhil Behari; Ramesh Raskar

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arXiv · 2603.06531

Spatial Calibration of Diffuse LiDARs

Nikhil Behari·Ramesh Raskar

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Abstract

Diffuse direct time-of-flight LiDARs report per-pixel depth histograms formed by aggregating photon returns over a wide instantaneous field of view, violating the single-ray assumption behind standard LiDAR-RGB calibration. We present a simple spatial calibration procedure that estimates, for each diffuse LiDAR pixel, its footprint (effective support region) and relative spatial sensitivity in a co-located RGB image plane. Using a scanned retroreflective patch with background subtraction, we recover per-pixel response maps that provide an explicit LiDAR-to-RGB correspondence for cross-modal alignment and fusion. We demonstrate the method on the ams OSRAM TMF8828.

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Nikhil Behari, Ramesh Raskar. 2026-03-06. Spatial Calibration of Diffuse LiDARs. https://arxiv.org/abs/2603.06531

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