A Refractive Index Sensitive Liquid Level Monitoring Sensor Based on Multimode Interference

Photonics

Takenobu Suzuki¹  Yasutake Ohishi¹  Tonglei Cheng²  Shuguang Li²  Xuenan Zhang²  Fang Wang²  Fan Zhang²  Xin Yan² 

[1] Research Center for Advanced Photon Technology, Toyota Technological Institute, 2-12-1, Hisakata, Tempaku, Nagoya 468-8511, Japan;State Key Laboratory of Synthetical Automation for Process Industries, College of Information Science and Engineering, Northeastern University, Shenyang 110819, China;

关键词: multimode interference;    SMF–NCF–SMF structure;    liquid level monitoring;    optical fiber sensor;   

DOI  :  10.3390/photonics7040089

来源: DOAJ

【 摘 要 】

According to the beam propagation method, a fiber refractive index-sensitive multimode interference (MMI) structure fabricated by splicing a self-made silica glass rod between two single mode fibers (SMF–NCF (no core fiber)–SMF structure) is proposed for liquid level monitoring. Theoretical and experimental investigation was carried out meticulously using a 4.5 cm and a 9.5 cm long silica glass rod. It is proved that the simple and economical sensor with the shorter length has high sensitivity, satisfactory repeatability, and favorable stability. The sensitivity climbs with the increase in refractive index of the measured liquid, which is 204 pm/mm for pure water, 265.8 pm/mm for 10% glycerin solution, and 352.5 pm/mm for 25% glycerin solution. The proposed sensor can be standardized in certain application circumstances to achieve accurate liquid level monitoring.

【 授权许可】

Unknown