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arXiv · 2310.09176

Histogram-less LiDAR through SPAD response linearization

Alessandro Tontini·Sonia Mazzucchi·Roberto Passerone·Nicolò Broseghini·Leonardo Gasparini
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Abstract

We present a new method to acquire the 3D information from a SPAD-based direct-Time-of-Flight (d-ToF) imaging system which does not require the construction of a histogram of timestamps and can withstand high flux operation regime. The proposed acquisition scheme emulates the behavior of a SPAD detector with no distortion due to dead time, and extracts the Tof information by a simple average operation on the photon timestamps ensuring ease of integration in a dedicated sensor and scalability to large arrays. The method is validated through a comprehensive mathematical analysis, whose predictions are in agreement with a numerical Monte Carlo model of the problem. Finally, we show the validity of the predictions in a real d-ToF measurement setup under challenging background conditions well beyond the typical pile-up limit of 5% detection rate up to a distance of 3.8 m.

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Alessandro Tontini, Sonia Mazzucchi, Roberto Passerone, Nicolò Broseghini, Leonardo Gasparini. 2023-10-13. Histogram-less LiDAR through SPAD response linearization. https://arxiv.org/abs/2310.09176

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