公开(公告)号：US06400878B1

公开(公告)日：2002-06-04

申请号：US09939742

申请日：2001-08-28

申请人： Katsuya Nagayama ,  Yuichi Ohga ,  Tatsuhiko Saitoh ,  Shinji Ishikawa ,  Ichiro Tsuchiya ,  Takenori Uchiyama

发明人： Katsuya Nagayama ,  Yuichi Ohga ,  Tatsuhiko Saitoh ,  Shinji Ishikawa ,  Ichiro Tsuchiya ,  Takenori Uchiyama

IPC分类号： G02B602

CPC分类号： G02B6/03627 ,  C03B37/02718 ,  C03B37/029 ,  C03B37/15 ,  C03B2201/12 ,  C03B2201/20 ,  C03B2201/31 ,  C03B2203/22 ,  C03B2205/56 ,  C03C13/04 ,  G02B6/02

摘要： An optical fiber preform 2 having a viscosity ratio R&eegr;=&eegr;0/&eegr;t of 2.5 or less between the core average viscosity &eegr;0 and the total average viscosity &eegr;t is prepared, and is drawn by a drawing furnace 11 so as to yield an optical fiber 3, which is then heated to a temperature within a predetermined range so as to be annealed by a heating furnace 21 disposed downstream the drawing furnace 11. Here, upon annealing in the heating furnace 21, the fictive temperature Tf within the optical fiber lowers, thereby reducing the Rayleigh scattering loss. At the same time, the viscosity ratio condition of R&eegr;≦2.5 restrains the stress from being concentrated into the core, thereby lowering the occurrence of structural asymmetry loss and the like. Hence, an optical fiber which can reduce the transmission loss caused by the Rayleigh scattering loss and the like as a whole, and a method of making the same can be obtained.

摘要翻译： 准备在芯平均粘度eta0与总平均粘度etat之间具有2.5或更小的粘度比Reta = eta0 / etat的光纤预制棒2，并由拉丝炉11拉伸以产生光纤3， 然后将其加热到预定范围内的温度，以便通过设置在拉丝炉11下游的加热炉21进行退火。这里，在加热炉21中退火后，光纤内的假想温度Tf降低，从而降低 瑞利散射损失。 同时，Reta <= 2.5的粘度比条件限制了应力集中到芯中，从而降低了结构不对称损失的发生等。 因此，可以获得可以降低由瑞利散射损耗等引起的传输损耗等的整体的光纤及其制造方法。