| 摘要 |
PURPOSE:Ion winds are blown on the surface of the optical fiber preform and the preform is softened by heating in a oven and drawn into a filament to ensure the removal of contaminants even if they closely sticks on the surface whereby optical fibers are produced with reduced breakage of the filament in the low loading region. CONSTITUTION:Preform 1 is fed into the core tube 4 of the oven at a constant rate Vp, softened with heaters 5 and taken up at a speed Vf. At this time, a high voltage is applied from a high voltage generator 12 through leads 2, 3 to electrode terminals 8, 9 to effect discharge near the gas inlets 2, 3. The sealing gas for the oven such as nitrogen gas is negatively charged and the anionized gas stream is blown to the surface of preform. The positive charges on the preform surface are neutralized and contaminants electrostatically sticking to the surface are blown off to clean the surface. Further, the surface of the preform has become electrically neutral, impurities formed in the oven do not stick to the preform. |
