Research On Temperature And Refractive Index Sensing Properties Of Conical Triple Cladding Quatez Specialty Fiber

As a novel sensor,optical fiber sensor has many advantages,such as the sensitive to the external environmental changing,fast response speed,strong resistance to electromagnetic interference,small size,easy preparation and so on.And they can be used for distributed measurement and remote sensing.So it can be used widely in the areas of electrical power system,medical diagnosis,environmental monitoring and aerospace engineering.Moreover,the tapered fiber is simple structure and high sensitivity,so it becomes a focus of research scholars at home and abroad.In this paper,three sensors with different structures have been fabricated based on the Mach-Zehnder interference principle,and the triple cladding quartz specialty fiber(TCQSF)is used as the sensing element.The temperature and refractive index sensing characteristics of these sensors have been studied.The main content is included as follows:Firstly,the background and the significance of the research project are analyzed.The domestic and international research status of different fiber temperature and refractive index sensors are analyzed.Moreover,the research contents and innovation of this article are introduced.Secondly,tapered TCQSF sensor,waist-enlarged TCQSF sensor and tapered TCQSF sensor with a temperature-sensitive glue are designed.And the sensing principle is analyzed in detail based on the Mach-Zehnder interference principle.Finally,the preparation processes of three kinds of conical TCQSF sensors were studied.And the sensors with different length and cone diameter are fabricated.The relationship between the length of TCQSF and the interference spectrum is discussed.The measurement platforms of temperature and refractive index are set up,and the relevant experiments are performed.The influence of the tapering length to the temperature and refractive index sensing characteristics of the tapered TCQSF sensor are discussed.The influence of the TCQSF length and cone diameter to the temperature and the refractive index sensing characteristics of the waist-enlarged TCQSF sensor are discussed.The influence of the tapering length and the temperature-sensitive glue to the temperature sensing characteristics of the tapered TCQSF sensor with a temperature-sensitive glue are discussed.