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

描述了用于同时感测温度和相对湿度（RH）的双D形光纤。D形光纤的平坦表面涂覆有作为热敏材料的甲苯和作为湿敏材料的聚乙烯。利用有限元方法，分析了D形光纤的金属膜厚度和抛光深度对传感性能的影响，并获得了最佳的结构参数。研究了温度和湿度感测特性，结果表明，在25°C至65°C和30％RH和70％RH的条件下，获得的温度和湿度灵敏度分别为1.02 nm /°C和0.79 nm /％RH，最大线性度为0.996和0.997。提出的光纤传感器展示了双参数检测的潜在应用。