High-Flux Count-Free Single-Photon 3D Cameras

高通量无计数单光子 3D 相机

Abstract: Single-photon cameras based on single-photon avalanche diode (SPAD) technology are gaining popularity for 3D sensing, thanks to their extreme sensitivity and time resolution. There are two key challenges with single-photon cameras that limit their widespread use: (i) they suffer from non-linear distortions called ”pile-up” when operated in high-photon-flux conditions, and (ii) they generate a large volume of raw photon data, creating a severe data bottleneck at each sensor pixel.

摘要： 基于单光子雪崩二极管（SPAD）技术的单光子相机凭借其极高的灵敏度和时间分辨率，在 3D 感知领域正日益普及。然而，单光子相机在广泛应用方面面临两个关键挑战：(i) 在高光子通量条件下工作时，会产生被称为“堆积效应”（pile-up）的非线性畸变；(ii) 它们会产生海量的原始光子数据，在每个传感器像素处造成严重的数据瓶颈。

In this work, we show that while compressive capture techniques successfully mitigate data transfer challenges, they exacerbate the effects of dead-time distortion because they fail to retain sufficient information about the photon detection history to allow post-processing pile-up correction via existing methods. We propose a new computational-imaging method that combines free-running capture with an analysis-by-synthesis software pipeline to mitigate pile-up distortions.

在这项工作中，我们指出，虽然压缩采集技术成功缓解了数据传输挑战，但它们加剧了死区时间畸变的影响，因为这些技术无法保留足够的关于光子检测历史的信息，从而导致无法通过现有方法进行后处理堆积效应校正。我们提出了一种新的计算成像方法，将自由运行采集与“分析-合成”（analysis-by-synthesis）软件流水线相结合，以减轻堆积畸变。

Our results with hardware emulations and full-scene and single-pixel simulations show that our method can reliably capture scene distance and reflectance over a wide range of illumination conditions. Our work will enable high-resolution SPAD cameras that are severely bandwidth-constrained to operate in real-world high-flux scenarios.

通过硬件仿真以及全场景和单像素模拟，我们的结果表明，该方法能够在广泛的照明条件下可靠地捕获场景距离和反射率。我们的研究将使那些带宽受限严重的高分辨率 SPAD 相机能够在现实世界的高通量场景中正常工作。