Underwater Single Photon Imaging System

High resolution 3D maps are required for an increasing number of key subsea applications from installation and operation of offshore wind energy, asset decommissioning, environmental monitoring, and defence. Quantum photonic detection technologies can offer a step change in the resolution, accuracy, coverage, and speed of generation of these maps compared to existing acoustic or traditional imaging solutions. The approach proposed in this project differs from other techniques, as it relies on state-of-the-art single-photon detection technologies, which allow for three-dimensional imaging with extremely low light level return, typically less than one photon per pixel (in the so-called "sparse-photon" regime) - that corresponds to high underwater attenuation.

Single-photon detection is a quantum technology which has recently been exploited for light detection and ranging (LiDAR) applications. This project exploits recent advances funded under the UK National Quantum Technology Programme in underwater single-photon LiDAR measurements and CMOS silicon single-photon avalanche diode (SPAD) detector array development. One major advantage for underwater imaging; it is in the ideal spectral region for CMOS based SPAD detectors, which have made significant recent advances. This project is led by the marine industry, addressing current industry requirements and will utilise bespoke CMOS SPAD arrays and laser sources for subsea terrain mapping. It is expected that the project will lead to other underwater applications - this project will act as a pathfinder to more widespread deployment of single-photon imaging in the UK subsea industry.

This project brings together key industrial and academic institutions with world-class backgrounds to collaboratively develop a commercially viable subsea mapping system based on the time-correlated single-photon counting (TCSPC) imaging technique. The key objective is to deliver a complete mapping system based on novel 2D spatial single-photon array detector technology, which can be deployed to a subsea vehicle and robustly generate 3D maps at high altitude above the sea floor.