Abstract:
The present invention is generally directed to a photonic bad gap fiber and/or fiber preform with a central structured region comprising a first non-silica based glass and a jacket comprising a second non-silica based glass surrounding the central structured region, where the Littleton softening temperature of the second glass is at least one but no more than ten degrees Celsius lower than the Littleton softening temperature of the first glass, or where the base ten logarithm of the glass viscosity in poise of the second glass is at least 0.01 but no more than 2 lower than the base ten logarithm of the glass viscosity in poise of the first glass at a fiber draw temperature. Also disclosed is a method of making a photonic bad gap fiber and/or fiber preform.
Abstract:
The present invention is generally directed to a photonic bad gap fiber and/or fiber preform with a central structured region comprising a first non-silica based glass and a jacket comprising a second non-silica based glass surrounding the central structured region, where the Littleton softening temperature of the second glass is at least one but no more than ten degrees Celsius lower than the Littleton softening temperature of the first glass, or where the base ten logarithm of the glass viscosity in poise of the second glass is at least 0.01 but no more than 2 lower than the base ten logarithm of the glass viscosity in poise of the first glass at a fiber draw temperature. Also disclosed is a method of making a photonic bad gap fiber and/or fiber preform
Abstract:
An optical fiber having a length can include a core and at least one cladding disposed about the core, where the one cladding can comprise at least first volumetric regions having a first refractive index n1 and second volumetric regions having a second refractive index n2, different from n1, and the first and second volumetric regions in any cross-section taken through the fiber can be randomly intermingled with one another, where the random intermingling of the first and second volumetric regions changes with changes in the location of the cross-section along the length of the fiber.
Abstract:
The present invention relates generally to a novel and unique class of gly materials and methods of making such materials in which substantially all of the anions are nitride ions, in contrast to the oxide ions of conventional optical glasses, or the fluoride ions of the more recently discovered fluoride optical glasses. The chemical nature of these new glasses dispose the glassy materials to a remarkable combination of desirable properties, including, but not limited to, high hardness, high refractive index and high softening temperature.
Abstract:
The present invention relates generally to a novel and unique class of gly materials and methods of making such materials in which substantially all of the anions are nitride ions, in contrast to the oxide ions of conventional optical glasses, or the fluoride ions of the more recently discovered fluoride optical glasses. The chemical nature of these new glasses dispose the glassy materials to a remarkable combination of desirable properties, including, but not limited to, high hardness, high refractive index and high softening temperature.
Abstract:
A method for fabricating a lens in which the lens composition is controlled by dynamic shaping and shadowing. A lens material is vaporized and directed to a substrate through an orifice which is rotating relative to the substrate about the lens axis and which has a non-uniform radial distribution. The lens material is condensed on the substrate to form a lens having a radially non-uniform but axially symmetrical distribution. Thereafter, the original orifice may be replaced by a complimentary orifice and another lens material vaporized and directed to the substrate through the replacement orifice which is also rotating relative to the substrate about the lens axis and which also has a non-uniform radial distribution. This second lens material condenses on the first condensed lens material to form a compound lens.
Abstract:
The present invention is generally directed to a method of making a hollow-core photonic band gap preform from a specialty glass by pressing a specialty glass through a die to form a tube wherein the outer transverse shape of the tube is a hexagon, triangle, quadrilateral, or other polygon; stretching the tube to form a micro-tube with approximately the same outer transverse shape as the tube; stacking a plurality of micro-tubes into a bundle minimizing voids between adjacent micro-tubes and forming a central longitudinal void wherein the plurality of micro-tubes within the bundle comprise an inner structured region of the preform and the central void of the bundle comprises a hollow core in the preform; and inserting the bundle into a jacket tube. Also disclosed are the hollow-core photonic band gap preform and fiber formed by this method.
Abstract:
A photonic band gap fiber and method of making thereof is provided. The fiber is made of a non-silica-based glass and has a longitudinal central opening, a microstructured region having a plurality of longitudinal surrounding openings, and a jacket. The air fill fraction of the microstructured region is at least about 40%. The fiber may be made by drawing a preform into a fiber, while applying gas pressure to the microstructured region. The air fill fraction of the microstructured region is changed during the drawing.
Abstract:
To overcome problems of fabricating conventional core-clad optical fibre from non-silica based (compound) glass, it is proposed to fabricate non-silica based (compound) glass optical fibre as holey fibre i.e. one contining Longitudinal holes in the cladding. This removes the conventional problems associated with mismatch of the physical properties of the core and clad compound glasses, since a holey fibre can be made of a single glass composition. With a holey fibre, it is not necessary to have different glasses for the core and cladding, since the necessary refractive index modulation between core and cladding is provided by the microstructure of the clad, i.e. its holes, rather than by a difference in materials properties between the clad and core glasses. Specifically, the conventional thermal mismatch problems between core and clad are circumvented. A variety of fibre types can be fabricated from non-silica based (compounds) glasses, for example: single-mode fibre; photonic band gap fibre; highly non-linear fibre; fibre with photosensitivity written gratings and other refractive index profile structures; and rare-earth doped fibres (e.g. Er, Nd, Pr) to provide gain media for fibre amplifiers and lasers.
Abstract:
A method is provided for molding from glass certain complex optical components, such as lenses, microlens, arrays of microlenses, and gratings or surface-relief diffusers having fine or hyperfine microstructures suitable for optical or electro-optical applications. Thereby, mold masters or patterns, which define the profile of the optical components, made on metal alloys, particularly titanium or nickel alloys, or refractory compositions, with or without a non-reactive coating are used. Given that molding optical components from oxide glasses has numerous drawbacks, it has been discovered in accordance with the invention that non-oxide glasses substantially eliminates these drawbacks. The non-oxide glasses, such as chalcogenide, chalcohalide, and halide glasses, may be used in the mold either in bulk, planar, or power forms. In the mold, the glass is heated to about 10–110° C., preferably about 50° C., above its transition temperature (Tg), at which temperature the glass has a viscosity that permits it to flow and conform exactly to the pattern of the mold.