Patent ID: 6434975
Filing Date: 2002-08-20
Classification: C03B,G02B

Abstract:
A method of making an optical fiber preform comprising the steps:depositing a coating of cladding glass particles on the outer surface of a cladding glass tube having first and second ends, inserting a plurality of tablets into said cladding glass tube, at least one optical characteristics of at least one of said tablets in said cladding glass tube being different than that of an adjacent tablet, each tablet having at least a central region of core glass, wherein the core region of at least a first of said tablets contains a dopant capable of amplifying light, and the core region of at least one tablet adjacent said first tablet is free from said dopant, heating the coated assembly to a temperature less than the sintering temperature of said cladding glass particles, flowing through said tube a gas selected from the group consisting of pure chlorine and chlorine mixed with a diluent gas, and thereafter heating the coated assembly to sinter said coating, thereby generating a radially-inwardly directed force that causes said tube to collapse onto and fuse to said tablets, and causing said cladding glass tube to shrink longitudinally, whereby adjacent tablets are urged toward one another and are fused to one another.