Diaphragm-Free Fiber-Optic Fabry-Perot Interferometric Gas Pressure Sensor for High Temperature Application

Abstract

A diaphragm-free fiber-optic Fabry-Perot (FP) interferometric gas pressure sensor is designed and experimentally verified in this paper. The FP cavity was fabricated by inserting a well-cut fiber Bragg grating (FBG) and hollow silica tube (HST) from both sides into a silica casing. The FP cavity length between the ends of the SMF and HST changes with the gas density. Using temperature decoupling method to improve the accuracy of the pressure sensor in high temperature environments. An experimental system for measuring the pressure under different temperatures was established to verify the performance of the sensor. The pressure sensitivity of the FP gas pressure sensor is 4.28 nm/MPa with a high linear pressure response over the range of 0.1–0.7 MPa, and the temperature sensitivity is 14.8 pm/°C under the range of 20–800 °C. The sensor has less than 1.5% non-linearity at different temperatures by using temperature decoupling method. The simple fabrication and low-cost will help sensor to maintain the excellent features required by pressure measurement in high temperature applications.

Critical assessment of relevant methods in the field of biosensors with direct optical detection based on fibers and waveguides using plasmonic, resonance, and interference effects

“…To increase the sensitivity of fiber Bragg grating sensors when measuring the refractive index, tapered fiber optical interferometer (without cladding) between two fiber grating areas was considered to have high sensitivity. This can be called a fiber Fabri-Perot interferometer, first used as a gas pressure high-temperature sensor [201]. This approach was used to detect biomarkers for breast cancer [27] to calibrate HER2 biomarkers, surface functionalization is improved (APTES, cross-linking glutaraldehyde, immobilization of HER2 antibody, blocking by bovine serum albumin) at minimized non-specific interaction.…”

Microstructured optical fiber based Fabry–Pérot interferometer as a humidity sensor utilizing chitosan polymeric matrix for breath monitoring

“…Among these, FP interferometers are a commonly used transducing platform to realize RH sensing as these are robust, and small in size. FP cavities are also used in the fabrication of a broad range of sensors to monitor pressure 18 , humidity 16 , force 19 , and strain 20 . Suspended core microstructured optical fibers (MOFs) consist of large air holes surrounding a small core which is only a few microns.…”

Capacitive Pressure Sensor With Integrated Signal-Conversion Circuit for High-Temperature Applications

“…However, this sensor has some disadvantages, such as signal attenuation with increasing test temperature and a short reading distance. In 2018, Liang [10] et al developed a diaphragm-less pressure sensor based on the fiber optic interference principle; this sensor was tested at a temperature of 800 ℃. Its sensitivity is 14.8 pm/C, and its nonlinearity is less than 1.5% at different temperatures.…”