USA As Represented by Secretary of the Navy

Reza Mossadegh

Jasbinder Singh Sanghera

Ishwar Dayal Aggarwal

Pablo C Pureza

Shyam S Bayya

Brian A Cole

A process includes the steps of disposing a solid core glass rod at a point removed from hot temperature that can cause crystallization in the core glass rod, disposing a solid clad glass rod at a point removed from the core glass rod; softening to the flowing condition the solid clad glass rod, transferring the softened clad glass to a lower point, the softened clad glass having a central void therethrough, heating the softened clad glass above its crystallization temperature, cooling the softened clad glass to a draw temperature, transferring the solid core glass rod into the central void in the softened glad glass, softening to the flowing condition the solid core glass rod with the heat from the softened and cooled clad glass, and drawing the core/clad, glass fiber by allowing the clad and core glasses to flow in the form of a fiber.

Multi heating zone apparatus and process for making core/clad glass fibers

This invention pertains to apparatus and process for making core/clad glass fibers. The apparatus includes a central tube or receptacle connected at the top to a pressure controller and terminating in a reduced section; a side tube or receptacle positioned at about the level of the upper portion of the central tube; an outer tube or receptacle disposed around the bottom portion of the central tube terminating in a smaller section which is concentric with and spaced directly below the section of the central tube; a side arm connecting the side tube and the outer tube; and furnaces around the side, outer, and the reduced sections of the central and the outer tubes. The process includes the steps of disposing a solid core glass rod at a point removed from hot temperature that can cause crystallization in the core glass rod, disposing a solid clad glass rod at a point removed from the core glass rod, softening to the flowing condition the solid clad glass rod, transferring the softened clad glass to a lower point, the softened clad glass having a central void therethrough, heating the softened clad glass above its crystallization temperature, cooling the softened clad glass to a draw temperature, transferring the solid core glass rod into the central void in the softened clad glass, softening to the flowing condition the solid core glass rod with the heat from the softened and cooled clad glass, and drawing the core/clad glass fiber by allowing the clad and core glasses to flow in the form of a fiber.

A core/clad glass optical fiber is made by melting a core glass rod and a adding glass rod in separate crucibles which are not concentric with respect to each other and the respective core and cladding glass melts passed out of contact with each other to a glass melt contacting zone proximate a fiber drawing orifice in which the cladding glass surrounds the core glass and a core/clad glass fiber is drawn. This process enables the clad glass fiber to be drawn directly from core and cladding glass rods without the need for a preform or forming a melt from glass chards or chunks, thereby reducing the cost of producing the fiber and also producing a glass clad optical fiber of high purity and excellent concentricity. Chalcogenide glass fibers having a concentricity of 100% have been made.

Apparatus for making optical fibers from core and cladding glass rods

A vertically disposed apparatus used to make core-clad optical fibers inces an inner elongated cylinder removably closed at the top and provided at the bottom with an inner exit port of a smaller diameter than the inner cylinder and an outer cylinder, disposed around the inner cylinder, removably closed at the top and provided at the bottom with an outer exit port of a smaller diameter than the outer cylinder. The inner exit port is of a smaller diameter than the outer exit port and is disposed directly above the outer exit port. The apparatus also includes a heater for heating the inner and outer cylinders and acces to the inner and the outer cylinders for individually pressurizing inner and outer cylinders. The process by which the core-clad optical fibers are made includes the steps of placing a solid glass core rod into the inner cylinder of the apparatus described above, placing a solid glass cladding tube into the outer cylinder, melting the core rod and the cladding tube, quickly cooling the molten core rod and cladding tube to the drawing temperature, individually pressurizing the molten core rod and cladding tube, and drawing the core-clad optical fiber through the exit ports.

Multi-cylinder apparatus for making optical fibers, process and product

A core/clad glass optical fiber is made by melting a core glass rod and a adding glass rod in separate crucibles which are not intersecting with respect to each other and the respective core and cladding glass melts passed out of contact with each other to a glass melt contacting zone proximate a fiber drawing orifice in which the cladding glass surrounds the core glass and a core/clad glass fiber is drawn. This process enables the clad glass fiber to be drawn directly from core and cladding glass rods without the need for a preform or forming a melt from glass chards or chunks, thereby reducing the cost of producing the fiber and also producing a glass clad optical fiber of high purity and excellent concentricity. Chalcogenide glass fibers having a concentricity of 100% have been made.

Growing community of inventors

Alexandria, VA, United States of America

Reza Mossadegh