Theoretical And Experimental Study Of The Large-scale Furnace Tapering Device

Because the tapered fiber optic device has special shape and properties, so it has been researched and used in many fields, such as tapered optical fiber sensors, fused biconical taper fiber optic coupler, wavelength-division multiplexing, filters, optical switches, optical modulators, microsphere lasers, supercontinuum light sources, fiber optic connectors and so on. The fiber couplers and wavelength-division multiplexers based on fused taper technology has been applied widely in various communications networks.The tapered fiber fabrication methods have been developed from the stable flame fused tapering technology to the movable via to the accuracy requirement and applications, which has higher accuracy and greater shape range. Meanwhile, the algorithm based on the relationship of the tapered shape and tapered parameters also appeared. The early shape result calculation for fixed flame fused tapering technology and the calculation theory of movable flame fused tapering technology are both very important to the development process of fused tapering technology. But those algorithm theories can be only used in the point flame. When the moveable flame width is wide, the existing theories can not be used to calculate the result accurately.Based on the theory of movable point flame fused tapering technology which was proposed by Birks, we propose the theory analysis and calculation method of movable large-zone furnace tapering technology based on discrete deducing method. In order to fit the theory analysis, we write the computer software with the help of LabVIEW program. The electronically controlled displacement and retractable heating system which are controlled by a single chip microcomputer, the movable large-zone furnace tapering device is composed by the electronically controlled displacement and retractable heating system. The calculation program to work out the tapered shape cruve by MATLAB software is also be programmed. This calculation program can calculate the tapered shape cruve by calculating the width, the moving speed, the moving distance, the frequency tapering of the heating flame, the stretch rate and the other stretch parameters. The theoretical estimated results fit the experimental measuring shape of the tapering fibers quite well. At the same time, we also calculate several curves with different stretch parameters, and analyse the relationship between each stretch parameter and the tapered shape curve. According to this relationship, it can work out the stretch parameters when the main parameters of tapered shape curve has been achieved in the future.