High-birefringence microfiber Sagnac interferometer based humidity sensor

SENSORS AND ACTUATORS B-CHEMICAL

卷:231

Article

Sun, Li-Peng¹  Li, Jie¹  Jin, Long¹  Ran, Yang¹  Guan, Bai-Ou¹ 

[1] Jinan Univ, Inst Photon Technol, Guangdong Prov Key Lab Opt Fiber Sensing & Commun, Guangzhou 510632, Guangdong, Peoples R China

关键词: Humidity sensor;    Fiber-optic sensors;    Micro-optical devices;   

DOI  :  10.1016/j.snb.2016.03.102

来源: Elsevier

【 摘 要 】

A relative humidity (RH) sensor based on a microfiber Sagnac loop interferometer is proposed and demonstrated. The sensor is formed by fusion splicing a high-birefringence elliptical microfiber into a fiber loop mirror without any humidity sensitive coating to the structure. Interferometric fringe with visibility of around 30 dB can be achieved in the transmission spectrum due to phase difference between the two polarization modes travelling through the microfiber region. The proposed structure presents high sensitivity up to similar to 201.25 pm/%RH, within an RH range from 30%RH to 90%RH. Moreover, we realize the sensitivity enhancement (up to similar to 422.2 pm/%RH) by inserting a reference Panda fiber into the fiber loop. The sensitivity is two to five times of magnitude higher than the counterparts in the literature. The measured response time is around 60 ms, which is much better than the previously-reported devices. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.olg/licenses/by-nc-nd/4.0/).

【 授权许可】

Free