The Fabrication And Sensing Characteristics Research Of Cascading Photonic Crystal Fiber Sensors

Optical fiber sensors have widely applications in industry, construction, national defense and the biomedical sciences due to their desirable advantages of small size,high sensitivity, and resistance to electromagnetic interference. In recent years, the development of various fiber optic sensors not only expand the conventional optical fiber detecting range, but also provide a foundation for the development of new type fiber optic sensors. Photonic Crystal Fiber(PCF) sensor is gradually becoming a hot research because of its flexible structure and special optical characteristics.In this thesis, a cascading PCF sensor is presented through researching the development of PCF sensor in recent years. We research the fabrication methods of the sensor and its sensing characteristics such as the refractive index, temperature,curvature and strain in detail. The major contents include:Firstly, the thesis introduces the research dynamics of fiber optic sensors in both domestic and abroad; and focuses on the research methods of different kinds of PCF sensors.Then, the thesis analyzes the sensing principle of cascading PCF sensor in theory,furthermore, study the transmitting models of the PCF using simulation method. Based on researching the preparation of cascading PCF sensor, the thesis research on the interference spectrum of the PCF sensor in different situations with the different displacement amounts, different welding current and different length of PCF.Once more, the thesis researches the refractive index and temperature properties of the PCF sensor. By analyzing the changes of the sensor interference spectrum with the outside refractive index and temperature, study the refractive index and temperature properties of the sensor using experimental methods.Finally, the thesis researches the curvature and strain properties of the PCF sensor,and experimentally studies the curvature properties and strain properties in the different welding current and the different length of PCF.