PBG Fibers for Gas Concentration Measurement

The idea of a high-sensitivity gas concentration measuring system based on a photonic bandgap fiber (PBG fiber) is studied. Several types of PBG fibers of various parameters have been designed. Core diameters range from 10.9 to 26.25 μm. The capillary gas flow rate within the fiber has been simulated and measured. The attenuation of newly produced fibers is investigated and the concentration of ammonia gas is measured using a proposed sensing system. A new method for cutting the fiber using an Ar ion beam in a vacuumed chamber is tested to obtain the required angle of the fiber's end, and to avoid the destruction of the cladding structure.