Method of making nitrogen-doped graded index optical waveguides
AssigneeCorning Glass Works
InventorsPeter C. Schultz, Raja R. Wusirika
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Abstract
A method of forming graded index, nitrogen-doped optical waveguides. A cylindrically-shaped porous preform comprising at least two oxides is initially formed. One of the oxides, which more readily reacts with nitrogen, has a greater concentration near the center of the preform than at the outer portion thereof. The preform is treated with a nitrogen-containing compound to form a porous body having a greater concentration of nitrogen in the central portion thereof. The porous preform is consolidated and drawn into an optical waveguide filament.
Claims8
A method of making a glass article comprising the steps of
- providing a cylindrically shaped glass preform containing throughout its mass a multiplicity of interconnected pores, said preform comprising at least two oxides having different affinities for nitrogen, the concentration of the oxide having the greatest affinity for nitrogen varying radially through said preform,
- heating said porous preform in a nitrogen-containing atmosphere at a temperature sufficient to cause nitrogen to react therewith, and
- heating said preform to a temperature sufficient to cause said preform to consolidate and form a dense glass article.
In the method of manufacturing a cylindrically shaped dense glass article having a gradient refractive index which comprises the steps of
- forming a porous preform,
- incorporating into said preform a dopant, the concentration of which is greatest in the central portion thereof, and
- consolidating said preform to form a dense glass article,
- the step of forming being characterized in that it comprises forming a porous preform comprising at least two oxides having different affinities for nitrogen, the concentration of the oxide having the greatest affinity for nitrogen being greatest in the central region thereof and decreasing with increasing radius, and the step of incorporating comprising heating said porous preform in a nitrogen-containing atmosphere at a temperature sufficient to cause nitrogen to react therewith, thereby forming a nitrogen-doped preform wherein the concentration of nitrogen is greatest in the central portion thereof, the nitrogen concentration decreasing with increasing radius.
Dependencies are inferred from the claim text.