A method of fabricating an optical fibre preform is disclosed comprising using a subtractive process on an optical monolith to define therein at least a transverse section of the optical fibre preform, wherein the transverse section comprises at least two regions with different refractive indexes. An optical fibre preform fabricated in accordance with the method is also disclosed along with a method of assembling optical components using a subtractive process to define a first interconnecting feature in or for use with a first optical component; using a subtractive process to define a second interconnecting feature in or for use with a second optical component; and coupling the first and second components together using the first and second interconnecting features such that the coupling dictates a passive alignment of the first and second components.

A multi-fiber light guide includes: light guiding fibers, each fiber including an elongated glass core; a glass cladding, the cores being surrounded by the cladding to form a rigid and continuous glass element, the cores having a higher refractive index than the cladding such that light can be guided by a total reflection along the cores, which end in two abutting faces of the glass element such that light can be guided along the cores from one abutting face to the other abutting face; and an ion exchange layer at each of the abutting faces, the glass of the cores and the glass of the cladding including alkali ions, which are at least partly exchanged by alkali ions of a higher atomic number within the ion exchange layer at the abutting faces, the exchanged alkali ions within the ion exchange layer imparting a compressive stress at the abutting faces.

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 method for drawing an optical fibre from an optical fibre preform with a core section, a cladding section, a first gap and a second gap. The optical fibre preform is attached to an optical fibre draw tower through a handle. In addition, the optical fibre preform is connected to a vacuum system to supply and remove gas from the first gap and the second gap. Moreover, the gas is supplied to create a thermal barrier between the core section and the cladding section during heating of the optical fibre preform. Further, the optical fibre preform is heated inside a heating furnace to draw the optical fibre from the optical fibre preform.

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.

An optical fibre including a core region defined along a central longitudinal axis of the optical fibre and a cladding region concentrically surrounds the core region of the optical fibre. In particular, the core region has a first radius r.sub.1 and a first refractive index n.sub.1. Moreover, the cladding has a second radius r.sub.2 and a second refractive index n.sub.2. Furthermore, the optical fibre has a step index profile.

An optical fiber having an axial direction and a cross section perpendicular to the axial direction, and a method and preform for producing such an optical fiber. The optical fiber is adapted to guide light at a wavelength λ, and includes a core region, an inner cladding region surrounding said core region, and at least one of a first type of feature including a void and a surrounding first silica material. The core, the inner cladding region and the first type of feature extends along said axial direction over at least a part of the length of the optical fiber. The first silica material has a first chlorine concentration of about 300 ppm or less.

Method of producing glass components and preforms for use in the method. The preform includes a primary rod having a constant outside diameter and a square bottom and a sacrificial tip having a first end attached to the bottom of the primary rod, a second end opposite the first end, and a hollow interior region extending from the first end to the second end. The sacrificial tip is circular in cross section and the first end of the sacrificial tip has an outside diameter equal to the outside diameter of the primary rod. When the preform is heated in a furnace, the sacrificial tip melts and collapses into a drawing bulb which either draws the primary rod directly into the glass fiber or results in a tapered (i.e. tipped) preform for subsequent fiber draw. Material waste as well as the drip time is reduced and the cladding-to-core ratio, crucial for waveguide properties, is maintained for the whole preform compared to a square cut preform without the sacrificial tip.

The present invention relates to a preform assembly and a method for drawing a multicore optical fibre and a holey fibre. Particularly, the preform assembly includes a hollow cylindrical tube, a plurality of discs stacked inside the hollow cylindrical tube and a plurality of core rods inserted in a plurality of through holes in each of the plurality of discs.

An automated large outside diameter preform tipping process. A zone of the preform is heated inside a furnace and softened. The preform tip is shaped and the process is controlled by the movement of the glass above and below the heating zone and by sensing the weight of the lower part of the preform, which in effect is a measure of the viscosity of the softened material. Once the correct viscosity is reached, the bottom holder is moved away from the top holder with a non-linear, accelerated velocity profile (derived from the FEM simulation of glass flow) which is precisely programmed and controlled so that the preform tip is optimally shaped (usually short and sharp tipped) with minimum waste and waveguide distortion when drawn into a fiber. The same concept of the non-linear, accelerated velocity profile can also be applied to other tipping processes such as horizontal preform tipping processes.