A method for manufacturing an optical fibre includes placing the powdery substance compactly in the fluorine doped tube to form a core section. The core section of the glass preform is defined along a longitudinal axis of the glass preform. In particular, the fluorine doped tube is sintered to solidify the powdery substance. Moreover, the glass preform is heated at high temperature to draw the optical fibre.

A method for manufacturing of an optical fibre preform (100) using optimized core particles includes optimization of particles of calcium aluminum silicate powder (104), utilizing the optimized core particles, sintering the optimized core particles inside a fluorine doped glass tube (106) and drawing of an optical fibre. Particularly, the optimization of the particles of calcium aluminum silicate powder (104) facilitates formation of the optimized core particles and the optimized core particles are filled inside the fluorine doped glass tube (106). Moreover, sintering of the optimized core particles solidifies and adheres smoothly with the fluorine doped glass tube (106) for manufacturing of the optical fibre preform (100).

A reduced diameter optical fibre preform positioned along a longitudinal axis includes a core section defined around the longitudinal axis and a cladding section circumferentially surrounding the core section. The reduced diameter optical fibre preform is manufactured by utilizing a calcium aluminum silicate rod and a fluorine doped glass cylinder.

The technology of this application relates to the field of communication technologies, and an optical fiber raw material composition, an optical fiber, and an optical fiber product. The optical fiber raw material composition includes components of the following molar percentages: AlF.sub.3 10%-50%, BaF.sub.2 3%-20%, CaF.sub.2 3%-20%, YF.sub.3 1%-15%, SrF.sub.2 3%-20%, MgF.sub.2 3%-20%, and TeO.sub.2 1%-35%. The optical fiber prepared by using the optical fiber raw material composition provided in this disclosure can be used in aspects such as a mid-infrared band transmission optical fiber, an optical fiber amplifier, a fiber laser, and an optical fiber sensor.

The present invention discloses a glass with high refractive index for fiber optic imaging elements with medium-expansion and fabrication method therefor, the glass comprising the following components in percentage by weight: SiO.sub.2 5-9%, Al.sub.2O.sub.3 0-1%, B.sub.2O.sub.3 23-28%, CaO 0-3%, BaO 6-12%, La.sub.2O.sub.3 30-34%, Nb.sub.2O.sub.5 4-8%, Ta.sub.2O.sub.5 0-1%, Y.sub.2O.sub.3 0-1%, ZnO 4-9%, TiO.sub.2 4-8%, ZrO.sub.2 4-6%, SnO.sub.2 0-1%. The present invention further provides a fabrication method for the glass with a high refractive index, comprising: putting raw materials quartz sand, aluminum hydroxide, boric acid or boric anhydride, calcium carbonate, barium carbonate or barium nitrate, lanthanum oxide, niobium oxide, tantalum oxide, yttrium oxide, zinc oxide, titanium dioxide, zirconium oxide and stannic oxide, etc. into a platinum crucible according to the requirement of dosing, melting at a high temperature, cooling and fining, leaking and casting to form a glass rod, and then annealing, cooling and chilling the molded glass rod.

The present invention discloses a glass with high refractive index for fiber optic imaging elements with medium-expansion and fabrication method therefor, the glass comprising the following components in percentage by weight: SiO.sub.2 5-9%, Al.sub.2O.sub.3 0-1%, B.sub.2O.sub.3 23-28%, CaO 0-3%, BaO 6-12%, La.sub.2O.sub.3 30-34%, Nb.sub.2O.sub.5 4-8%, Ta.sub.2O.sub.5 0-1%, Y.sub.2O.sub.3 0-1%, ZnO 4-9%, TiO.sub.2 4-8%, ZrO.sub.2 4-6%, SnO.sub.2 0-1%. The present invention further provides a fabrication method for the glass with a high refractive index, comprising: putting raw materials quartz sand, aluminum hydroxide, boric acid or boric anhydride, calcium carbonate, barium carbonate or barium nitrate, lanthanum oxide, niobium oxide, tantalum oxide, yttrium oxide, zinc oxide, titanium dioxide, zirconium oxide and stannic oxide, etc. into a platinum crucible according to the requirement of dosing, melting at a high temperature, cooling and fining, leaking and casting to form a glass rod, and then annealing, cooling and chilling the molded glass rod.

The present invention discloses a fabrication method and use of a ?40 mm large-size and high-contrast fiber optic image inverter, belonging to the field of manufacturing of fiber optic imaging elements. The light-absorbing glass for preparing the ?40 mm large-size and high-contrast fiber optic image inverter consists of the following components in molar percentage: SiO.sub.2 60-69.9, Al.sub.2O.sub.3 1.0-10.0, B.sub.2O.sub.3 10.1-15.0, Na.sub.2O 1.0-8.0, K.sub.2O 3.0-10.0, MgO 0.1-1.0, CaO 0.5-5.0, ZnO 0-0.1, TiO.sub.2 0-0.1, ZrO.sub.2 0.1-1.0, Fe.sub.2O.sub.3 3.0-6.5, Co.sub.2O.sub.3 0.1-0.5, V.sub.2O.sub.5 0.51-1.5 and MoO.sub.3 0.1-1.0. The fiber optic image inverter has the advantages of low crosstalk of stray light, high resolution and high contrast.

A molding device and a molding method for an optical fiber preform are provided. The molding device includes a rotating mechanism, an extrusion mechanism, and a cylinder mold that is of a cylindrical structure with two ends each having an opening. After a hollow cladding sleeve is obtained by rotating the cylinder mold through the rotating mechanism, a molten core glass is then reversely extruded into the cladding sleeve in the cylinder mold from bottom to top by the extrusion mechanism to prepare the optical fiber preform.

In a unit gravity environment, a glass preform is encased in a material to generate an encased glass preform. The material remains solid at the glass preform's crystal melting temperature and is inert with respect to the glass preform. The encased glass preform is placed in a microgravity environment and heated to a temperature above the crystal melting temperature until the glass preform melts and is free of crystals, wherein a crystallite-free glass preform is encased within the material. The crystallite-free glass preform is then cooled in the microgravity environment to generate a solid crystallite-free glass preform encased within the material. While still in the microgravity environment, the material encasing the solid crystallite-free glass preform is removed in the microgravity environment and the solid crystallite-free glass preform is polished. A glass optical fiber is then drawn from the solid crystallite-free glass preform in the microgravity environment.

The present invention discloses a fabrication method and use of a 40 mm sized fiber optic image inverter, belonging to the field of manufacturing of fiber optic imaging elements. The light-absorbing glass for preparing the 40 mm sized fiber optic image inverter consists of the following components in molar percentage: SiO.sub.2 60-69.9, Al.sub.2O.sub.3 1.0-10.0, B.sub.2O.sub.3 10.1-15.0, Na.sub.2O 1.0-8.0, K.sub.2O 3.0-10.0, MgO 0.1-1.0, CaO 0.5-5.0, ZnO 0-0.1, TiO.sub.2 0-0.1, ZrO.sub.2 0.1-1.0, Fe.sub.2O.sub.3 3.0-6.5, Co.sub.2O.sub.3 0.1-0.5, V.sub.2O.sub.5 0.51-1.5 and MoO.sub.3 0.1-1.0. The 40 mm sized fiber optic image inverter has the advantages of low crosstalk of stray light, high resolution and high contrast.