Supercontinuum methane ranging based on boundary-feature triangulation

Accurate localization of methane leaks is important for environmental monitoring and safety. However, existing concentration measurement methods often cannot provide both high precision and distance information at the same time. This study proposes and experimentally tests a triangulation method that uses a supercontinuum light source and the plume's boundary features. The method leverages methane absorption in the 1630-1700 nm band, detects quick absorption changes at the plume edge, and uses triangulation geometry to find the leak source. On the same test platform, we compared this method with baseline triangulation and scanning-ranging techniques. The boundary-feature triangulation kept the measurement error between +0.1 cm and +1.0 cm, with an average error of about 0.41 cm, much better than the baseline method (average: 1.49 cm) and scanning method (some points up to 1.7 cm). The method shows fast response, good linearity, and concentrated errors, making it suitable for quick and reliable on-site methane leak localization and monitoring.