Long-range depth profiling of camouflaged targets using single-photon detection

Abstract

We investigate the reconstruction of depth and intensity profiles from data acquired using a customdesigned time-of-flight scanning transceiver based on the time-correlated single-photon counting technique. The system had an operational wavelength of 1550 nm and used a Peltier-cooled InGaAs/InP single-photon avalanche diode detector. Measurements were made of human figures, in plain view and obscured by camouflage netting, from a stand-off distance of 230 m in daylight using only submilliwatt average optical powers. These measurements were analyzed using a pixelwise cross correlation approach and compared to analysis using a bespoke algorithm designed for the restoration of multilayered three-dimensional light detection and ranging images. This algorithm is based on the optimization of a convex cost function composed of a data fidelity term and regularization terms, and the results obtained show that it achieves significant improvements in image quality for multidepth scenarios and for reduced acquisition times.

Beyond coincidence: using all the data in Hong-Ou-Mandel interferometry

“…Note that this is similar to the time-of-flight protocols of Ref. [22,23,28], where direct timing information is used to construct an image. The typical resolutions involved in such a set-up are 10-30 ps, although Ref.…”

“…a cell membrane, a delay can be induced in the path of a photon by allowing it to pass through the sample, accompanied by a second photon which does not pass through the sample. The simplest, and perhaps most obvious, way to measure this delay would be to place detectors at the end of both photons' paths and measure the difference in their respective arrival times, an approach similar to a direct time-of-flight measurement [22,23]. However, the time-resolution of conventional single-photon detectors is orders of magnitude too poor to capture the precision needed for these measurements to provide the desired nanoscale resolution.…”

High-resolution 3D imaging through dense camouflage nets using single-photon LiDAR

“…The computational imaging algorithms have witnessed remarkable progress in processing the single photon data of complex scenes efficiently [15][16][17] . Moreover, photon-efficient imaging algorithms [18][19][20][21][22] have shown good performance in dealing with low return signals and high background noise, which has been successfully demonstrated in several challenging scenarios including imaging through clutter [14,23] , long-range depth imaging [24][25][26][27][28][29] , non-line-of-sight imaging [30][31][32] , and imaging through high levels of scattering media [33][34][35][36][37][38][39] .…”

64 × 64 GM-APD array-based readout integrated circuit for 3D imaging applications

“…Using the Geiger mode avalanche photodiode (GM-APD) detector and readout integrated circuit (ROIC), the single-photon detection technique can be employed for accurate time-of-flight (TOF) measurement and photon counting [1,2]. It has been widely used in various applications, such as laser ranging and three-dimensional (3D) imaging [2], weak light detection, and accurate identification and tracking of camouflage targets [3].…”