Research Of The Hollow Core Photonic Bandgap Fiber For Gas Sensor

Photonic crystal fiber (PCF for short) is a new class of optical fiber developed in recent years, divided into modified-total internal reflection photonic crystal fiber (M-TIR-PCF for short) and photonic bandgap photonic crystal fiber (PBG-PCF for short). We studied on PBG-PCF in this dissertation. Due to its special structure and light propagation mechanism, PBG-PCF performs superiorly to common fibers in many aspects, and it presents wide application prospects in many fields. The gas sensors provide high sensitivity, immunity to electromagnetic field, remote control and using under difficult circumstances. The gas sensors using hollow core photonic bandgap photonic crystal fiber can improve the detection sensitivity further. The main contents of this dissertation are as follows:1. Sum up the research process on the application of the photonic crystal fiber and fiber-optic senor. The optical basic principles, excellent features, applications of the PCF and PBG-PCF have been summarized. And we have summarized something about fiber-optic sensor in this dissertation.2. Through analyzed the advantages of the gas sensors using hollow core photonic bandgap photonic crystal fiber, the specific parameters are calculated for the hollow core photonic bandgap fibers which are used for the gas sensors by means of plane wave method and finite element method for applying the hollow core photonic bandgap fiber to the CO, CH4, C2H2 gas sensing and detecting. The specific parameters include the radius of the core of fiber, the radius and distance between two air holes. The results show that the in-core transmission power is more than 90%, which indicate that it can improve the detection sensitivity.