Research On Vernier Effect Sensitization Fiber Interferometer Senso

The development of science has put forward higher requirements for the performance of sensors,such as biomedical,environmental monitoring,aerospace and other fields need high resolution,improving sensitivity is an effective way to achieve high resolution sensors.In recent years,vernier effect has been introduced into fiber optic interferometer sensor technology,which effectively improves the detection sensitivity of fiber optic interferometer sensor.In this paper,based on the vernier effect of optical fiber interferometer sensor research,innovation and optimization of optical vernier sensitization scheme.The specific work content is as follows:1.The fiber optic Fabry-Perot(FP)temperature sensor based on parallel vernier interferometer is studied.The sensor consists of a sensor interferometer and a reference interferometer.Parallel structure has the advantages of simple manufacturing process,flexible and adjustable,anti electromagnetic interference and so on.According to the sensing principle of Fabry-Perot interferometer,a detailed preparation scheme was designed,and experimental verification was carried out in the range of 51℃ to 55℃.The temperature sensitivity of a single sensor interferometer was about 2.015nm/℃,and that of a parallel verniers interferometer was 10.053nm/℃.The results show that the parallel structure has a significant sensitization effect on temperature measurement.2.An optical fiber FP temperature sensor based on virtual vernier interferometer is proposed.The sensor consists of a sensor interferometer and a virtual reference interferometer.The sensor interferometer was experimentally measured,the virtual reference interferometer was prepared by interference spectrum simulation experiment,and the parallel connection was realized by processing interference spectrum data.The influence of cavity length variation on interference spectrum and vernier envelope spectrum of parallel vernier interferometer is analyzed.The experimental results show that the temperature sensitivity of the virtual parallel vernier interferometer is 10.033 nm/℃ in the range of 51℃ to 55℃,and the temperature sensitivity is 2,3,4,5,6 times by changing the length of the cavity.The results show that the virtual reference interferometer instead of the real object can avoid the influence of uncontrollable factors such as manufacturing and measurement environment on the experimental results,and is more stable,and the temperature sensitivity can be regulated within a reasonable range.3.A microfiber coupler refractive index sensor based on birefringence vernier effect is proposed.The coupler is a birefringent waveguide formed by heating and melting two single-mode optical fibers and pulling the cone.The light source passes through the coupling cone region to excite X/Y polarization state.After the coupling of the two polarization states,a vernier effect is formed at the output port.The narrower the waist diameter of the cone,the stronger the peripheral evanescent field,so the response to refractive index solution is more sensitive.The experimental results show that the highest refractive index sensitivity of the glycerol solution is 37943.777nm/RIU in the range of 1.3341～1.3380 RIU,and the linear response is good.