Super-resolution single-photon imaging at 8.2 kilometers

Abstract

Single-photon light detection and ranging (LiDAR), offering single-photon sensitivity and picosecond time resolution, has been widely adopted for active imaging applications. Longrange active imaging is a great challenge, because the spatial resolution degrades significantly with the imaging range due to the diffraction limit of the optics, and only weak echo signal photons can return but mixed with a strong background noise. Here we propose and demonstrate a photon-efficient LiDAR approach that can achieve sub-Rayleigh resolution imaging over long ranges. This approach exploits fine sub-pixel scanning and a deconvolution algorithm tailored to this long-range application. Using this approach, we experimentally demonstrated active three-dimensional (3D) single-photon imaging by recognizing different postures of a mannequin model at a stand-off distance of 8.2 km in both daylight and night. The observed spatial (transversal) resolution is ∼5.5 cm at 8.2 km, which is about twice of the system's resolution. This also beats the optical system's Rayleigh criterion. The results are valuable for geosciences and target recognition over long ranges.

Full Waveform LiDAR for Adverse Weather Conditions

“…The effect of such adversarial conditions has not been systematically studied in an automotive context where established benchmarks tend to provide good weather data [33]. Li et al [34] observed that turbulence effects were substantial in reducing the achievable resolution in azimuth and elevation at long range (8.2 Km) using a single-photon system, especially during the day and in an urban environment. Pawlikowska et al [35], [36], have performed an extensive study of the effects of turbulence on a photon counting system at 1550 nm using both single element and arrayed detectors, and Henrikson and Sjoberg [37] have investigated methods for correction of scintillation effects in laser radar systems.…”

Robust 3D Reconstruction of Dynamic Scenes From Single-Photon Lidar Using Beta-Divergences

“…Fast and reliable reconstruction of 3D scenes using singlephoton light detection and ranging (lidar) is extremely important for a variety of applications, including environmental monitoring [1], [2], autonomous driving [3] and defence [4], [5]. While 3D profiles can be obtained from a range of modalities, single-photon lidar (SPL) offers appealing advantages, including low-power imaging, a capability for longrange imaging [6]- [8] or imaging in complex media such as fog/smoke [5] and turbid underwater environments [9] with excellent range resolution (of the order of millimetres [10]).…”

“…However, the resulting model makes the estimation process more complicated and slower iterative schemes (optimization-based [19] or simulation-based [24]) are classically used. Strong ambient levels are encountered in many practical applications, for instance in long-range imaging applications in free-space [6]- [8] and challenging imaging applications through scattering media such as turbid underwater environments [9], [31], [32] and through fog/smoke [5]. It is thus extremely important to develop methods adapted to such challenging observation conditions.…”

Expectation-Maximization Based Approach to 3D Reconstruction From Single-Waveform Multispectral Lidar Data

“…D EPTH measurement from light detection and ranging (Lidar) systems has received an increasing interest over the last decades, as it allows reconstruction of 3D scenes at high resolution [1], [2]. In particular, single-photon Lidar has enabled unprecedented 3D reconstruction results, at longer ranges [3]- [5], through obscurants [6] and underwater [7]- [9], using extremely low illumination powers. This performance improvement thus makes single-photon Lidar particularly attractive for automotive, robotics and defense applications.…”