Photon-efficient imaging with a single-photon camera

Abstract

Reconstructing a scene's 3D structure and reflectivity accurately with an active imaging system operating in low-light-level conditions has wide-ranging applications, spanning biological imaging to remote sensing. Here we propose and experimentally demonstrate a depth and reflectivity imaging system with a single-photon camera that generates high-quality images from ∼1 detected signal photon per pixel. Previous achievements of similar photon efficiency have been with conventional raster-scanning data collection using single-pixel photon counters capable of ∼10-ps time tagging. In contrast, our camera's detector array requires highly parallelized time-to-digital conversions with photon time-tagging accuracy limited to ∼ns. Thus, we develop an array-specific algorithm that converts coarsely time-binned photon detections to highly accurate scene depth and reflectivity by exploiting both the transverse smoothness and longitudinal sparsity of natural scenes. By overcoming the coarse time resolution of the array, our framework uniquely achieves high photon efficiency in a relatively short acquisition time.

Super-resolution single-photon imaging at 8.2 kilometers

“…Another challenge in long range condition is the exceedingly weak echo signal. Recently, to deal with such extremely low-light levels, some photon-efficient algorithms were proposed [12][13][14][15][16]. However, most of them were only tested in the laboratory at a short distance.…”

“…Furthermore, computational imaging algorithms have seen remarkable progress to process the single-photon data efficiently [11]. High-quality 3D structure has been demonstrated in the laboratory environment by an active imager detecting only one photon per pixel (PPP), based on the approaches of first-photon imaging [12], pseudo-array [13,14], single-photon camera [15], unmixing signal/noise [16] and machine learning [17]. These algorithms have the potential to improve the imaging range and quality significantly.…”

Perspectives for Applications of Quantum Imaging

“…This led to the measurement of images with on average, less than one photon per image pixel . Similar algorithms have been already applied for photon‐efficient classical imaging . However, as has been discussed before, the SNR of the measured data can be inherently better for quantum imaging schemes based on correlation measurements, especially for low photon numbers.…”

Studying fermionic ghost imaging with independent photons

“…High resolution ghost imaging [14] is possible when compressive sensing is employed [15]. Computational ghost imaging [16] shows great potential in single-pixel camera [17][18][19]. Ghost imaging with X-ray and atoms were also reported [20][21][22].…”