Low water peak optical waveguide and method of manufacturing same

A method of fabricating a cylindrical glass body for use in manufacturing optical waveguide fiber, said method comprising the steps of:

• a) chemically reacting at least some of the constituents of a moving fluid mixture comprising at least one glass-forming precursor compound and an oxidizing medium, the reaction resulting in the formation of a silica-based reaction product;
• b) depositing at least a part of said reaction product on a substrate to form a porous body thereon, at least a portion of said porous body including hydrogen bonded to oxygen;
• c) removing the substrate from said porous body, thereby forming a centerline hole extending axially through said porous body;
• d) consolidating and drying at least a portion of said porous body to form a glass preform;
• and
• e) closing the centerline hole and said drying, consolidating, and closing steps are performed under conditions suitable to result in a solid glass body including a centerline region having a weighted average OH content of less than about 1 ppb.

A method of fabricating a cylindrical glass body for use in manufacturing optical waveguide fiber, said method comprising the steps of:

• a) chemically reacting at least some of the constituents of a moving fluid mixture comprising at least one glass-forming precursor compound and an oxidizing medium, the reaction resulting in the formation of a silica-based reaction product;
• b) depositing at least a part of said reaction product on a substrate to form a porous body thereon, at least a portion of said porous body including hydrogen bonded to oxygen;
• c) removing the substrate from said porous body, thereby forming a centerline hole extending axially through said porous body;
• d) consolidating and drying at least a portion of said porous body to form a glass preform;
• and
• e) closing the centerline hole;
• wherein said closing step comprises preventing at least the centerline hole from being exposed to an atmosphere comprising a hydrogen containing compound subsequent to step d);
• wherein said preventing step comprises:
• the step of creating a vacuum within the centerline hole;
• positioning a plug in the centerline hole at each end of said porous body, and heating said porous body in an inert gas atmosphere to a temperature sufficient to sinter each end of said porous body to said plugs, thereby sealing the centerline hole;
• and exposing the centerline hole to a pressure reducing atmosphere through at least one end of said porous body during said heating step;
• wherein at least one of said plugs is breakable;
• and
• wherein said closing step comprises the steps of:
• positioning said glass body in a furnace;
• breaking said plug;
• exposing the centerline hole to a pressure-reducing atmosphere;
• heating said blank during said exposing step;
• and
• drawing said glass body into a cane having an outside diameter smaller than the outside diameter of said glass body, and said drying, consolidating, and closing steps are performed under conditions suitable to result in a solid glass body suitable to make an optical fiber having an optical attenuation of less than about 0.35 dB/km at a wavelength of 1380 nm.

A method of fabricating a cylindrical glass body for use in manufacturing optical waveguide fiber, said method comprising the steps of:

• a) chemically reacting at least some of the constituents of a moving fluid mixture comprising at least one glass-forming precursor compound and an oxidizing medium, the reaction resulting in the formation of a silica-based reaction product;
• b) depositing at least a part of said reaction product on a substrate to form a porous body thereon, at least a portion of said porous body including hydrogen bonded to oxygen;
• c) removing the substrate from said porous body, thereby forming a centerline hole extending axially through said porous body;
• d) positioning plugs in the centerline hole at each end of said porous body;
• and
• e) consolidating and drying at least a portion of said porous body to form a glass preform under conditions suitable to result in a glass body including a centerline region having a weighted average OH content of less than about 1 ppb.