Abstract: A method of processing an optical fiber includes drawing the optical fiber from a heated glass source, reheating the optical fiber, and cooling the optical fiber under vacuum at a cooling rate less than the cooling rate of the optical fiber in air at 25° C. and 1 atm. Cooling the optical fiber under vacuum is conducted after reheating the optical fiber. Cooling the optical fiber under vacuum reduces the rate of heat transfer from the optical fiber, which may enable further relaxation of the glass and reduction in the fictive temperature of the optical fiber. A system for processing an optical fiber includes a furnace containing a fiber preform, a first positioner, a reheating device, and a treatment device downstream of the reheating device, the treatment device operable to cool the optical fiber under vacuum to reduce the rate of heat transfer from the optical fiber.

Abstract: A system and method for processing an optical fiber includes a treatment device disposed downstream of a furnace and including a treating zone. The treating zone includes a fiber inlet and fiber outlet and is configured to cool the optical fiber at a reduced pressure below ambient pressure and at a slow cooling rate less than an ambient cooling rate. A nozzle assembly is disposed at one or more of the fiber inlet, the fiber outlet, upstream of the treating zone, and downstream of the treating zone. The nozzle assembly includes multiple baffle plates defining a number of nozzle chambers, each nozzle chamber having a nozzle chamber pressure, wherein each baffle plate includes an orifice having a predetermined effective orifice diameter through which the optical fiber passes. Each nozzle chamber is configured to sequentially change a nozzle chamber pressure between the reduced pressure and ambient pressure.

Abstract: A method of processing an optical fiber includes drawing the optical fiber from a heated glass source, reheating the optical fiber, and cooling the optical fiber under vacuum at a cooling rate less than the cooling rate of the optical fiber in air at 25° C. and 1 atm. Cooling the optical fiber under vacuum is conducted after reheating the optical fiber. Cooling the optical fiber under vacuum reduces the rate of heat transfer from the optical fiber, which may enable further relaxation of the glass and reduction in the fictive temperature of the optical fiber. A system for processing an optical fiber includes a furnace containing a fiber preform, a first positioner, a reheating device, and a treatment device downstream of the reheating device, the treatment device operable to cool the optical fiber under vacuum to reduce the rate of heat transfer from the optical fiber.

Abstract: A method of processing an optical fiber includes drawing the optical fiber from a heated glass source, reheating the optical fiber, and cooling the optical fiber under vacuum at a cooling rate less than the cooling rate of the optical fiber in air at 25° C. and 1 atm. Cooling the optical fiber under vacuum is conducted after reheating the optical fiber. Cooling the optical fiber under vacuum reduces the rate of heat transfer from the optical fiber, which may enable further relaxation of the glass and reduction in the fictive temperature of the optical fiber. A system for processing an optical fiber includes a furnace containing a fiber preform, a first positioner, a reheating device, and a treatment device downstream of the reheating device, the treatment device operable to cool the optical fiber under vacuum to reduce the rate of heat transfer from the optical fiber.

Abstract: A system and method for processing an optical fiber includes a treatment device disposed downstream of a furnace and including a treating zone. The treating zone includes a fiber inlet and fiber outlet and is configured to cool the optical fiber at a reduced pressure below ambient pressure and at a slow cooling rate less than an ambient cooling rate. A nozzle assembly is disposed at one or more of the fiber inlet, the fiber outlet, upstream of the treating zone, and downstream of the treating zone. The nozzle assembly includes multiple baffle plates defining a number of nozzle chambers, each nozzle chamber having a nozzle chamber pressure, wherein each baffle plate includes an orifice having a predetermined effective orifice diameter through which the optical fiber passes. Each nozzle chamber is configured to sequentially change a nozzle chamber pressure between the reduced pressure and ambient pressure.

Abstract: A method of processing an optical fiber includes drawing the optical fiber from a heated glass source, reheating the optical fiber, and cooling the optical fiber under vacuum at a cooling rate less than the cooling rate of the optical fiber in air at 25° C. and 1 atm. Cooling the optical fiber under vacuum is conducted after reheating the optical fiber. Cooling the optical fiber under vacuum reduces the rate of heat transfer from the optical fiber, which may enable further relaxation of the glass and reduction in the fictive temperature of the optical fiber. A system for processing an optical fiber includes a furnace containing a fiber preform, a first positioner, a reheating device, and a treatment device downstream of the reheating device, the treatment device operable to cool the optical fiber under vacuum to reduce the rate of heat transfer from the optical fiber.