Abstract: A method of manufacturing a cane suitable for forming an optical fiber, and a method of forming an optical fiber from the cane. A core composition having about 20% to 30% by weight of P2O5 is formed. An inner cladding composition is formed on an outer surface of the core composition and the core composition and the inner cladding composition are consolidated into a preform having a core and an inner cladding while substantially closing a center line hole of the preform. An outer cladding composition is formed on the preform to define a cane. The cane can then be transformed into an optical fiber.

Abstract: The disclosed invention includes an inventive drying agent. The drying agent includes at least one halide and at least one reducing agent. Preferably, the reducing agent includes a compound that will react with an oxygen by-product of the reaction of the halide and water, or the reaction of the halide and an impurity in the preform. The invention also includes a method of drying a soot preform. The method includes disposing the soot preform in a furnace. The furnace is charged with the drying agent which includes the halide and the reducing agent. Heat is then supplied to the furnace. Suitable drying agents for use in the disclosed invention include a mixture of Cl2 and CO; a mixture of Cl2, CO and CO2; and POCl3.