Research On Interferometric Fiber Optic Air Pressure Sensor And Its Sensitization Characteristics

Optical fiber air pressure sensor,as a kind of air pressure detection device,has strong application prospects in industrial production,cargo storage,medical and health and other fields because of its strong mechanical strength and anti-electromagnetic interference characteristics.Research.These mainly include air pressure sensors of pure silica structure and optical fiber air pressure sensors based on materials.However,the sensitivity of traditional pure silica optical fiber air pressure sensors is low,and the gas desorption time of material-based optical fiber air pressure sensors is too long.This paper aims to improve the sensitivity of the optical fiber pressure sensor and shorten the desorption time of the sensor to the gas.Starting from the structure of the traditional pure silica optical fiber pressure sensor,through the exploration and research of the gas pressure characteristics of the gas sensing material,it is modified and then applied to On the pure silica optical fiber air pressure sensor,an interferometric air pressure sensor based on gas-sensing material is prepared.The main content and research results of the full text are as follows:(1)A fiber-optic Mach-Zehnder interferometer(MZI)air pressure sensor was designed and fabricated.Theoretical analysis of its air pressure and temperature sensing principle was carried out,and its theoretical sensitivity was calculated,and then its sensing performance was verified by air pressure and temperature experiments,and finally the air pressure and temperature of the bare fiber Mach-Zehnder interferometer were obtained.The response characteristics are used to explore the theoretical basis and structural design for the next two chapters to improve its air pressure sensitivity.(2)In order to improve the air pressure sensitivity of the above-mentioned fiber Mach-Zehnder interferometer(MZI)air pressure sensor,find the best gas-sensing material to sensitize it,using Mach-Zehnder interferometer(MZI)and Fabry-Perot The gas pressure properties of polydimethylsiloxane(PDMS)were investigated by an interferometer(FPI).Aiming at the refractive index and linear expansion pressure characteristics of PDMS,the refractive index and linear expansion pressure characteristics of PDMS are explored by using optical experiments combined with optical fiber sensing.The use of optical experiments can greatly improve the accuracy and accuracy of experimental results.(3)In view of the problem of long gas desorption time when the above-mentioned gas-sensing material PDMS is used in combination with optical fiber pressure sensors,MOF particles were added to the above-mentioned gas-sensing material PDMS to modify it,and then it was applied to the above-mentioned optical fiber Mach-Zeng German interferometer(MZI)barometric pressure sensor.Its pressure sensitivity and gas desorption time were tested and explored through experiments.Compared with the Mach-Zehnder interferometer(MZI)of pure quartz structure and the Mach-Zehnder interferometer(MZI)combined with pure PDMS gas-sensing material,While the sensitivity has been greatly improved,the gas desorption time has also been greatly shortened.