Optical fiber preform producing method, optical fiber preform, and optical fiber

摘要

An object of the present invention is to provide a method for manufacturing an optical fiber preform having a great diameter by reducing an eccentricity or a non-circularity of a core, an optical fiber preform having an small non-circularity and a complex refractive index profile, even with a great diameter, and an optical fiber that is applicable as a dispersion compensating fiber. The present invention involves a rod-in collapse process in which a glass rod is fixed within a glass pipe (or a dummy pipe attached to an end portion) via an aligning jig. The fixation via the aligning jig is made at one end or both ends, the aligning jig has a cylindrical shape with or without one or more reduced diameter portions. When fixed at one end, a heating and integrating process is preferably made from an opposite end. Employing the glass rod and the glass pipe having a refractive index distribution, a complex profile can be realized.