TITLE:
Temperature Compensated Solution Concentration Measurement Based on a Cascaded SMS/LPFG Fiber Structure
AUTHORS:
Jin Wang, Li Wang, Xueqiong Su, Huanhuan Yan
KEYWORDS:
Long Period Fiber Grating, Multimode Mode Fiber, Solution Concentration, Temperature, Dual-Wavelength Matrix
JOURNAL NAME:
Optics and Photonics Journal,
Vol.11 No.8,
August
3,
2021
ABSTRACT: In this paper, a hybrid optical fiber structure for solution concentration measurement with the temperature compensation is proposed. The structure consists of long period fiber grating (LPFG) and single mode-multimode-single mode (SMS) fiber structures. The sensing mechanism of the device is studied and verified by experiments. LPFG is sensitive to solution concentration and is affected by temperature crosstalk. SMS structure is not affected by solution concentration, but sensitive to ambient temperature. It can be used as a temperature compensation system. The sensitivity coefficients of LPFG and SMS on temperature and concentration were measured experimentally, and a dual-wavelength matrix was established to realize simultaneous measurement of solution temperature and concentration.