Patent ID: 6602448
Filing Date: 2003-08-05
Classification: B29D

Abstract:
A method of forming a graded-refractive-index optical fiber, said method comprising the steps of:providing a tube of an amorphous fluoropolymer having a first index of refraction, said tube having a longitudinal axis and a radial axis and having a bore extending along said longitudinal axis, said bore having an opening at an end thereof, filling said bore, subsequent to said step of providing a tube, with a liquid dopant material having a second index of refraction different from said first index of refraction to a form a raw preform, heating said raw preform at a selected temperature and for a sufficient duration to provide diffusion of said dopant material in the direction of said radial axis to form a selected graded refractive index, said heating further providing a sufficient flux of said fluoropolymer into said filled bore to fuse said bore and form a finished preform having a core with said selected graded refractive index, and drawing said finished preform to form an optical fiber having said selected refractive index.