Study On The Point-level Optical Fiber Liquid-level Sensor And The Stability Of The Non-Functional Optical Fiber Pressure Sensor System

With the development of the optical fiber communication, computer technique, fiber technique and semi-conductor photoelectric compounds technique, optical fiber sensing technology become more and more important during the past 30 years in the international fiber field because they have more advantages than other sensors. The purposes of this thesis are to study the stability of the non-functional optical fiber pressure sensor system, and to optimize the structure of the optical fiber liquid-level sensor head which is sensitive to the refractive index of surrounding media.In the first part of the thesis, the sensing principle of a fiber-fused type liquid-level sensor is analyzed qualitatively. The geometric structure of the sensor head and optical characteristic are studied using SEM technology firstly .The experimental results indicate the optimum angle of the microoptical sensor head are around 50?In the second part of the thesis, the study background of the non-functional intensity-modulated optical fiber pressure sensor system is reviewed at the beginning; The main optical and photoelectrical compounds of the sensor system are designed; The stability of a whole intensity-modulated fiber optical pressure sensor system are studied.