Research On Fiber Optic Sensing Technology Based On Fabry-Pérot Cavity And Michelson Interferometer

It will inevitably become a major advantage of development to get a variety of key information quickly and accurately in the information society.Optical fiber sensing technology has attracted a great deal of attention since the time it was invented because of its compact structure,free from electromagnetic interference,corrosion resistance,high stability and convenient remote measurement and other advantages.It is widely used in national defense and military,environmental protection,medicine,biology,chemistry,aerospace and quality monitoring a nd other fields.Optical fiber sensors can measure the temperature,pressure,humidity,refractive index,strain and other physical quantities quickly and accurately,while most of the current fiber optic sensors pursue the new materials excessively,require complex fabrication workmanship,and is difficult to process.All these restriction will increase the cost of the fiber optic sensors,have an adverse impact on their large-scale use and promotion.So this paper launched the design and ex periment of sensor characteristics for the Fabry-Perot fiber sensor and Michelson fiber sensor.The main contents of this paper are as follows:(1)It makes a simple introduction about the research background and significance of this paper,the classification of fiber optic sensors.It focuses on the analysis and the domestic and foreign research status of Fabry-Perot,Mach-Zehnder and Michelson fiber optic sensors.(2)A Fabry-Perot fiber sensor is designed by using quartz capillary and ordinary single-mode fiber according to the welding method with the guidance of a large number of experiments.Then,we describe the structure and manufacturing process briefly,carry out a certain theoretical analysis using Matlab.The results of the sensor's sensitivity show that the sensitivity of temperature is 0.16pm/?,and the sensitivity of the strain is 3.72pm/??,that is,the sensor is not sensitive to temperature.So we can solve the temperature cross-sensitive problem when measuring the strain.(3)We design a Michelson fiber sensor by fusing a single-mode fiber after the spherical structure which is made of single-mode fiber.We describe its structure and production process briefly,and make an analysis about its sensing principle.The results of the sensor's sensitivity show that its sensitivity of temperature is 54.69 pm/?,and the sensitivity of the strain is 0.90 pm/??,that is,the sensor is not sensitive to strain.So we can solve the strain cross-sensitive problem when measuring the temperature.(4)We make a new optical fiber sensor by cascading the Fabry-Perot cavity and the spherical structure together.And then introduce the characteristics of its spectrum,carry out an experiment about its sensing characteristics.The results of the experiments show that it exhibits different responses of temperature and strain at different interference wavelengths.According to this characteristic,the sensor can achieve simultaneous measurement of temperature and strain.