Optical fiber and method of manufacturing the same

Abstract

An optical fiber 1 comprising a glass portion 2 having a core 2 a and a cladding 2 b , and one or more covering layers 3 formed around the glass portion 2 , in which an arrangement form of the covering layer 3 with respect to the glass portion 2 in cross section perpendicular to a longitudinal direction thereof is changed continuously in the longitudinal direction thereof.

1 - 11 . (canceled) 
   
   
       12 . A method of manufacturing an optical fiber, comprising the steps of:
 drawing a bare optical fiber from a rotating preform;   passing the drawn bare optical fiber through a die in a state where the drawn bare optical fiber rotates while describing a predetermined minute circle, thereby coating resin onto an outer periphery of the drawn bare optical fiber with the die; and   curing the coated resin.   
   
   
       13 . A method of manufacturing an optical fiber, comprising the steps of:
 drawing a bare optical fiber from a preform;   passing the drawn bare optical fiber through a die which rotates with a center thereof deviating from a center of the optical fiber and coating resin onto an outer periphery of the bare optical fiber with the die; and   curing the coated resin.   
   
   
       14 . A method of manufacturing an optical fiber, comprising the steps of:
 drawing a bare optical fiber from a preform;   passing the fiber-drawn bare optical fiber through a die which is arranged with a center thereof deviating from a center of the optical fiber and coating resin onto an outer periphery of the bare optical fiber with the die;   swinging the optical fiber coated with the resin after passing through the die and twisting the preform and the bare optical fiber, which are positioned on an upstream; and   curing the coated resin.   
   
   
       15 . The method according to  claim 12 , wherein an ejection port shape of the die is uncircularized. 
   
   
       16 . A method of manufacturing an optical fiber, comprising the steps of:
 drawing a bare optical fiber from a preform;   passing the drawn bare optical fiber through a die which rotates with a center thereof deviating from a center of the optical fiber and coating resin onto an outer periphery of the bare optical fiber with the die; and   curing the coated resin, wherein an ejection port shape of the die is uncircularized.   
   
   
       17 . The method according to  claim 14 , wherein an ejection port shape of the die is uncircularized.