Fiber loop ring-down optical fiber grating gas pressure sensor

• Published in: Optics and lasers in engineering Vol. 48; no. 12; pp. 1262 - 1265
• Main Authors: Tang, Daqing, Yang, Dexing, Jiang, Yajun, Zhao, Jianlin, Wang, Haiyan, Jiang, Shiquan
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2010; Elsevier
• Subjects: Diffraction gratings; Exact sciences and technology; Fiber Bragg grating; Fiber loop ring-down; Fiber optics; Fibers; Fundamental areas of phenomenology (including applications); Gas pressure; General equipment and techniques; Gratings; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Liquids; Optical elements, devices, and systems; Optical fibers; Optics; Other fiber-optical devices; Physics; Pressure sensors; Sensor; Sensors; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Spectra; Fiber Bragg grating; Gas pressure; Fiber loop ring-down; Sensor; Optical fibers; Bragg gratings; Diffraction gratings; Pressure measurement; Grating in fiber; Gas detector
• ISSN: 0143-8166; 1873-0302
• DOI: 10.1016/j.optlaseng.2010.06.005

A kind of bare fiber Bragg grating (FBG) gas pressure sensor based on fiber loop ring-down is presented, in which there are no sensitizing means or assistant structure on the bare FBG. The pressure sensitivity is analyzed theoretically via discussing the relationship between the ring-down time and the gas pressure. By detecting the ring-down time at different gas pressure levels, the gas pressure characteristics of the bare FBG are investigated in the time domain. The experimental results demonstrate that there exists a linear dependence of the pressure applied to the bare FBG on the ring-down time. A high sensitivity of −0.384 μs/MPa (being equivalent to −240 pm/MPa) could be achieved, which is 79 times larger than that of the optical spectral analyzer interrogated. This kind of pressure sensor could be used for gas or liquid pressure measurement.