A method of processing an optical fiber includes drawing the optical fiber from an optical fiber preform within a draw furnace, the optical fiber extending from the draw furnace along a process pathway, the optical fiber comprising at least one halogen-doped core; and drawing the optical fiber through at least one slow cooling device positioned downstream from the draw furnace at a draw speed. The at least one slow cooling device exposes the optical fiber to a slow cooling device process temperature greater than or equal to 800° C. and less than or equal to 1600° C. The draw speed is such that the optical fiber has a residence time of at least 0.1 s in the at least one slow cooling device. An optical fiber made by such a process is also disclosed.

The present disclosure relates to a method for forming a glass, ceramic or composite material. The method may involve initially forming a plurality of tubes and then performing a coating operation to coat the plurality of tubes with materials containing metal or metalloid elements, including inorganic compounds, organometallic compounds, or coordination complexes to form coated tubes. The method may further include performing at least one of a thermal operation or a thermochemical operation on the coated tubes to form a solid glass, ceramic, or composite structure with dimensions representing at least one of a rod or fiber.

An optical fiber may comprise a core doped with one or more active ions to guide signal light from an input end of the optical fiber to an output end of the optical fiber, a cladding surrounding the core to guide pump light from the input end of the optical fiber to the output end of the optical fiber, and one or more inserts formed in the cladding surrounding the core. The core may have a geometry (e.g., a cross-sectional size, a helical pitch, and/or the like) that varies along a longitudinal length of the optical fiber, which may cause an absorption of the pump light to be modulated along the longitudinal length of the optical fiber.

The present application provides a process of fabrication of erbium and ytterbium-co-doped multielements silica glass based cladding-pumped fiber for use as a highly efficient high power optical amplifier.

An optical fiber may comprise a core doped with one or more active ions to guide signal light from an input end of the optical fiber to an output end of the optical fiber, a cladding surrounding the core to guide pump light from the input end of the optical fiber to the output end of the optical fiber, and one or more inserts formed in the cladding surrounding the core. The core may have a geometry (e.g., a cross-sectional size, a helical pitch, and/or the like) that varies along a longitudinal length of the optical fiber, which may cause an absorption of the pump light to be modulated along the longitudinal length of the optical fiber.

A method for preparing a glass composite wavelength converter comprising the steps of providing at least one phosphor material, providing a powder of glass components, mixing the phosphor material and the powder of glass components, thereby preparing a first mixture, adding at least one oxidizing agent to the first mixture, mixing the oxidizing agent with the first mixture, thereby preparing a second mixture, applying pressure and current to the second mixture, thereby preparing a glass composite wavelength converter is described. Furthermore, a glass component wavelength converter and a light source are described.

Annealing treatments for modified titania-silica glasses and the glasses produced by the annealing treatments. The annealing treatments include an isothermal hold that facilitates equalization of non-uniformities in fictive temperature caused by non-uniformities in modifier concentration in the glasses. The annealing treatments may also include heating the glass to a higher temperature following the isothermal hold and holding the glass at that temperature for several hours. Glasses produced by the annealing treatments exhibit high spatial uniformity of CTE, CTE slope, and fictive temperature, including in the presence of a spatially non-uniform concentration of modifier.

A method of producing a glass vessel includes holding a borosilicate glass tube with a first holding device, and holding an open end portion of the glass tube with a second holding device such that the second holding device is spaced apart from the first holding device. Heat is applied to the glass tube by a burner to separate the open end portion and form a bottom portion on the open end portion. Fire-blast treatment of an inner surface of the open end portion with a flame from a point burner is performed during at least a part of (i) applying heat to the borosilicate glass tube for separation, (ii) applying heat to the separated open end portion for bottom portion formation, and/or (iii) a period applying heat to the separated open end portion and prior to releasing the glass vessel from the second holding device.

Preparation of halogen-doped silica is described. The preparation includes doping silica with high halogen concentration and sintering halogen-doped silica to a closed-pore state. The sintering includes a high pressure sintering treatment and a low pressure sintering treatment. The high pressure sintering treatment is conducted in the presence of a high partial pressure of a gas-phase halogen doping precursor and densifies a silica soot body to a partially consolidated state. The low pressure sintering treatment is conducted in the presence of a low partial pressure of gas-phase halogen doping precursor and transforms a partially consolidated silica body to a closed-pore state. The product halogen-doped silica glass exhibits little foaming when heated to form fibers in a draw process or core canes in a redraw process.

A method for manufacturing a multicore optical fiber includes a step of forming ring-shaped closed-end holes to axially extend from a first end toward a second end of a glass rod; a step of heating bottom parts of the ring-shaped closed-end holes and softening center rods surrounded by the ring-shaped closed-end holes; a step of pulling out the center rods toward a side of the first end, forming columnar closed-end holes from the ring-shaped closed-end holes, and treating the glass rod as a cladding material; a connecting step of connecting a supporting pipe to the first end; an inserting step of inserting core rods into the columnar closed-end holes after the connecting step; and a drawing step of drawing the cladding material and the core rods while heating a portion near the second end and integrating the cladding material and the core rods after the inserting step.