Research On Refractive Index Sensor Based On Fused Tapered Photonic Crystal Fiber

As a new type of special optical fiber, Photonic Crystal Fiber (PCF) hascompletely different structure and optical transmission characteristic compared withsingle mode fiber (SMF), especially flexibility on the structure design. So, it hasdeveloped a new field for production and application of optical fiber devices. Atapered PCF is a special kind of optical waveguide transmission medium. Throughbeing tapered, the internal structure and transmission performance of the PCF havebeen changed, and there are some great potential significances for studying therelative PCF devices.This paper introduces the research situation of the tapered PCF in recent years indetail, and the study on fabrication technology and sensing characteristic of the fusedtapered PCF is proposed. The main contents include:First, the necessity of research and the status of theory, fabrication andapplication on tapered PCF are introduced. The paper study theoretically thefundamental model and interference characteristic of the tapered PCF in order to builda foundation for experimental investigating on fabrication technology and sensingcharacteristic of the tapered PCF.Next, a fabrication method of the fused tapered PCF sensor is investigated. Theoptimal fusion splicing conditions between PCF and SMF is analyzed throughnumerous experiments. The tapered PCF sensor is fabricated based on fusion splicingtechnology and fused taper technique. Geometric parameters of the tapered PCF aremeasured through microscopic image, and its optical properties are also analyzed, andthen, the relationship between the optical properties and structure parameters isobtained.Once more, the interference characteristic of tapered PCF sensor is researchedthrough analyzing their spectrum of different external environment. Differentconcentrations of glycerol, chloride aqueous solution and different temperature aredetected. Finally, a kind of intermittent cooling fused tapered PCF sensor is proposed. Withthe method, a high sensitivity tapered PCF sensor is produced. The responses ofdifferent refractive index environments are explored.