Open AccessHigh-accuracy hybrid fiber-optic Fabry-Pérot sensor based on MEMS for simultaneous gas refractive-index and temperature sensing
Author(s) -
Xue Wang,
Shuang Wang,
Junfeng Jiang,
Kun Liu,
Peng Zhang,
Wen Bing Wu
Publication year - 2019
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.27.004204
Subject(s) - refractive index , materials science , optics , microelectromechanical systems , fabry–pérot interferometer , fiber optic sensor , optical fiber , temperature measurement , wavelength , optoelectronics , physics , quantum mechanics
We present a high-accuracy fiber-optic Fabry-Pérot (F-P) sensor capable of simultaneously measuring the temperature and gas refractive-index (RI). The sensor consists of a silicon F-P cavity for temperature sensing and a glass F-P cavity with a side groove for gas RI sensing. Two F-P cavities are simply fabricated and connected in series by microelectromechanical system (MEMS) techniques. The hybrid F-P sensor produces a superposition of signals. Changes in temperature and RI can be separated and detected by a fast Fourier transform (FFT) and the wavelength-tracing method. The experimental results demonstrate that the sensitivities of the proposed sensor are 80.7 pm/°C from 10 °C to 60 °C and over 1535.8 nm/RIU in the gas RI range of 1.0000248-1.0007681. Furthermore, the gas RI measurement reaches a high accuracy of ± 7.6 × 10 -6 RIU, owing to the temperature compensation. In addition, the measured precisions of the temperature and gas RI are 1.07 × 10 -3 °C and 2.73 × 10 -8 RIU, respectively.