MANUFACTURE OF OPTICAL FIBER PREFORM

摘要

PURPOSE:To obtain a preform for low-loss single-mode optical fiber having excellent polarization maintaining property, by depositing glass soot to the side surface of a core glass rod while periodically changing the rotational speed of the rod. CONSTITUTION:A glass rod 31 for core or having a core-clad structure is rotated at periodically varying rotational speed. The flame stream 35 is blasted from the synthetic torch 34 to the side surface of the glass rod 31, and glass soot synthesized by the flame hydrolysis is deposited to the surface to form an elliptic porous glass layer 32. The product is heated and sintered at high temperature to obtain a clear preform.