Research On Temperature Sensing Characteristics Of Grapefruit Microstructure Optical Fiber Based On Liquid Crystal Coating

In recent years,temperature detection has become an issue of great concern.It is inseparable from temperature detection in the fields of power system,chemical industry,aerospace,biomedicine and marine development.Therefore,the research of optical fiber temperature sensor has aroused the interest of a large number of researchers at home and abroad.At the same time,because liquid crystal is a kind of filling material sensitive to temperature,liquid crystal is more and more widely used in optical fiber sensors.Based on the analysis and summary of the research status of liquid crystal temperature sensors at home and abroad,based on the mode interference principle of optical fiber and the temperature characteristics of liquid crystal,three different structures of grapefruit microstructure optical fiber temperature sensors based on liquid crystal coating are proposed and prepared in this paper.The specific contents mainly include the following aspects.Firstly,based on the structural parameters of grapefruit microstructure optical fiber(GMF),the geometric model is established and the transmission mode of GMF is simulated;The mode interference principle of GMF fiber and the characteristics of liquid crystal with temperature are analyzed.Secondly,the preparation method of liquid crystal coated coarse conical GMF sensor is studied,and the transmission spectrum of uncoated liquid crystal GMF sensor with different discharge times is analyzed.The temperature experiment of liquid crystal coated coarse conical GMF sensor with different diameter of coarse cone and different length of GMF is carried out,and its temperature sensing characteristics are analyzed.Thirdly,the preparation method of liquid crystal coated dislocation GMF sensor is studied,and the transmission spectrum of uncoated liquid crystal GMF sensor with different dislocation amount is analyzed.The temperature experiment of liquid crystal coated dislocation GMF sensor with different dislocation amount and different GMF length is carried out,and its temperature sensing characteristics is analyzed.Finally,the preparation method of liquid crystal coated coarse cone dislocation GMF sensor is studied.The liquid crystal coated coarse cone dislocation GMF sensor with different discharge times and different GMF length is prepared.The temperature experiment of the GMF sensors is carried out,and its temperature sensing characteristics is analyzed.