Subcentimeter depth resolution using a single-photon counting time-of-flight laser ranging system at 1550 nm wavelength

Abstract

We demonstrate subcentimeter depth profiling at a stand off distance of $330\mathrm{m}$ using a time-of-flight approach based on time-correlated single-photon counting. For the first time to our knowledge, the photon-counting time-of-flight technique was demonstrated at a wavelength of $1550\mathrm{nm}$ using a superconducting nanowire single-photon detector. The performance achieved suggests that a system using superconducting detectors has the potential for low-light-level and eye-safe operation. The system’s instrumental response was $70\mathrm{ps}$ full width at half-maximum, which meant that $1\mathrm{cm}$ surface-to-surface resolution could be achieved by locating the centroids of each return signal. A depth resolution of $4\mathrm{mm}$ was achieved by employing an optimized signal-processing algorithm based on a reversible jump Markov chain Monte Carlo method.