Study On The Manufacture Technology Of The Infrared Photonic Crystal Fibers

The infrared photonic crystal fiber(PCF) is mainly used in CO2laser energy transmitting insurgical operation and industry. But PCF’s structure is complicated, all the existing manufactureprocesses have certain degrees of shortage, the infrared PCF has many problems in the fabrication,so it is hard to be in the way of becoming practical.In this paper, impact of infrared PCF structure error to the properties casued by the fabricationprocess is analyzed, and how to control the fiber structure error to improve the properties isdiscussed, and the uniformity and stability of the drawing condition is considered. The result showsthat fine errors of the infrared PCF, such as the error of the air hole ratio and the error of the latticeconstant, have large influence on the properties of the fiber, and loss of the actual fabricationstructure increases to1.984dB/km, the loss of the actual structure can be reduced to0.01dB/kmafter increasing the clad air hole number. Under ideal drawing condition, through controlling thedrawing temperature T, feeding speed Ufand pulling speed Ud, the size of the hollow capillary canbe uniform. But during the drawing of the perform, extra negative pressure must be plused to offsetthe surface tension. The clad and core capillary need1050pa and300pa while Uf=2mm/min,Ud=15m/min, and T=1850°C. The negative pressure technology can be optimizated, the corecapillary’s duty ration can be properly reduced to0.39, then the negative pressure can be equal tothe clad layer and the core, and it will be easier to apply the negative pressure. On the uniformityand stability of the drawing condition, the impact of uniformity can be reduced by using insulationdevice or changing the initial air hole ratio, the impact of stability can be controlled throughmonitor device.