Abstract:
A photonic band gap fiber and method of making thereof is provided. The fiber is made of a germanate glass comprising at least 30 mol % of a germanium oxide 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 90%. 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:
An optical fiber according to Tran U.S. Pat. No. 5,274,728 is improved by chemically etching the surface of the GeO2-based glass perform with an acid solution based on a mixture of HNO3 and water.
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:
The invention relates to lasers and fiber optics. An amplifying optical fiber operating at a wavelength in the range of 1000-1700 nm comprises an oxide glass core to provide amplification and at least one oxide glass cladding. According to the invention the core contains oxides of elements selected from the group consisting of silicon, germanium, phosphorus, bismuth, aluminum, gallium at concentration of bismuth oxide of 10-4-5 mol %, concentration of silicon and germanium oxides, taken together or separately, of 70-99.8999 mol %, concentration of aluminum and gallium oxides, taken together or separately, of 0.1-20 mol % concentration of phosphorus oxide from 0 to 10 mol %, and provides a maximum optical gain at least 10 times greater than the nonresonant loss factor in the optical fiber. An outside oxide glass cladding comprises fused silica. The optical fiber core has an absorption band in the 1000 nm region, pumping to which region provides an increased efficiency of power conversion of pump light into luminescence light in the 1000-1700 nm range as compared to pumping to another absorption bands in which pumping brings about luminescence in the 1000-1700 nm range. The optical fiber emits luminescence in the range of 1000-1700 nm when excited by light with wavelengths in the range of 750-12000 nm and a half-height width of the luminescence band of more than 120 nm, and luminescence band boundaries defined as points in which the luminescence intensity drops twice relative to the intensity in the luminescence band maximum lie within the 1000-1700 nm spectral range.
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:
A method of manufacturing glass for an optical transmission body includes the steps of precipitating an oxide of a glass forming element by the hydrolysis reaction of a halogen compound of the glass forming element in the liquid phase, adding phosphoric acid to the precipitate to produce a phosphate, removing the water from the phosphate and vitrifying the phosphate by heating.
Abstract:
The present invention discloses an optical fiber wave-guide for signal transmission in which the signal fiber has a linear thermal expansion co-efficient in all of the fiber elements above 15.times.10.sup.-7 /.degree.C. in which the outer mantle is composed of the silicon dioxide modified glass, and the optical fiber wave-guide is composed of an inner silicon dioxide-free mantle employing germanium oxide and other components and has an inner silicon dioxide-free core which is composed of germanium oxide and optionally other additives. The fiber is produced according to the chemical vapor deposition process, and preferably has a refractive index gradient which has the shape of a parabola.
Abstract:
A method and apparatus for making a substantially void-free preform for a microstructured optical fiber using a one-step process is provided. A preform is prepared from specialty glasses using a direct extrusion method. A die for use with the direct extrusion method is also provided, and a method for drawing the preform into a HC-PBG fiber for use in transmitting infra-red wavelength light is also provided. The preform comprises an outer jacket made of solid glass, a cladding having a plurality of air holes arranged in a desired pattern within the jacket, and a core which is hollow.
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.