Few-photon imaging at 1550 nm using a low-timing-jitter superconducting nanowire single-photon detector

TL;DR

This paper presents a high-resolution, low-noise 3D imaging system at 1550 nm using a superconducting nanowire single-photon detector with low jitter, enabling accurate depth imaging with minimal processing.

Contribution

It introduces a novel depth imaging approach utilizing a low-jitter SNSPD at 1550 nm for direct depth determination without complex algorithms.

Findings

Achieved millimeter resolution depth imaging of low-signature objects.

Demonstrated superior accuracy over traditional Gaussian fitting methods.

Enabled 3D reconstruction with reflectivity overlay.

Abstract

We demonstrated a laser depth imaging system based on the time-correlated single-photon counting technique, which was incorporated with a low-jitter superconducting nanowire single-photon detector (SNSPD), operated at the wavelength of 1550 nm. A sub-picosecond time-bin width was chosen for photon counting, resulting in a discrete noise of less than one/two counts for each time bin under indoor/outdoor daylight conditions, with a collection time of 50 ms. Because of the low-jitter SNSPD, the target signal histogram was significantly distinguishable, even for a fairly low retro-reflected photon flux. The depth information was determined directly by the highest bin counts, instead of using any data fitting combined with complex algorithms. Millimeter resolution depth imaging of a low-signature object was obtained, and more accurate data than that produced by the traditional Gaussian fitting method was generated. Combined with the intensity of the return photons, three-dimensional reconstruction overlaid with reflectivity data was realized.