Humidity-insensitive optical fibers for distributed sensing applications

Humidity is a critical environmental factor in various applications, and its temperature dependence must be considered when developing thermo-hygrometer fiber sensors. The optical fibers that con-stitute the sensor must have a temperature reference, which should be resistant to humidity to avoid cross-sensitivities. This paper presents two innovative optical fibers insensitive to humidity over tem-peratures ranging from -20 degrees C to 55 degrees C. To the best of our knowledge, the novel standard size opti -cal fibers coated with acrylate and silicone are tested under controlled conditions using an optical time-domain reflectometer sensor based on Rayleigh scattering. The sensor achieves meter-range resolution over kilometers of length with a response time of few minutes.(c) 2023 Optica Publishing Group