Abstract

A double D-shaped optical fiber for simultaneous temperature and relative humidity (RH) sensing is described. The flat surfaces of the D-shaped optical fiber are coated with toluene as a thermally sensitive material and polyethylene as a humidity-sensitive material. Using the finite element method, the effects of the metal film thickness and polished depth of the D-shaped optical fiber on the sensing performance were analyzed and the optimal structural parameters were obtained. The temperature and humidity sensing properties were studied and show that temperature and humidity sensitivities of 1.02 nm/°C and 0.79 nm/% RH were obtained from 25 °C to 65 °C and 30% RH and 70% RH with maximum linearities of 0.996 and 0.997. The proposed optical fiber sensor demonstrates potential applications for dual-parameter detection.

摘要

描述了一种用于同时进行温度和相对湿度 (RH) 传感的双 D 形光纤。D形光纤的平坦表面涂有作为热敏材料的甲苯和作为湿敏材料的聚乙烯。采用有限元方法，分析了D形光纤的金属膜厚和抛光深度对传感性能的影响，得到了最优结构参数。研究了温度和湿度传感特性，结果表明，从 25 °C 到 65 °C 和 30% RH 和 70% RH 的温度和湿度灵敏度为 1.02 nm/°C 和 0.79 nm/% RH，最大线性度为 0.996和 0.997。所提出的光纤传感器展示了双参数检测的潜在应用。