Abstract:
A mixed quartz powder contains quartz powder and two or more types of doping element in an amount of from 0.1 to 20 mass %. The aforementioned doped elements include a first dope element selected from the group consisting of N, C and F, and a second dope element selected from the group consisting of Mg, Ca, Sr, Ba, Sc, Y, Ti, Zr, Hf, the lanthanides and the actinides. The “quartz powder” is a powder of crystalline quartz or it is a powder of glassy SiO2 particles. It is made form natural occurring quartz or it is fabricated synthetically. The “quartz powder” may be doped. The compounding ratio of the total amount (M1) of the aforementioned first elements and the total amount (M2) of the aforementioned second elements as the ratio of the number of atoms (M1)/(M2) is preferably from 0.1 to 20. Al as well as the aforementioned doped elements is preferably included in a mixed quartz powder of this invention.
Abstract:
A silica optical fiber is provided, which contains a pure-silica core and a cladding layer formed on the pure-silica core, wherein the pure-silica core contains a C element and has a content of elements belonging to the third period-the seventh period of the periodic table, except Si element that constitutes the quartz structure, of not more than 100 ppm. The present invention can provide a silica optical fiber superior in the resistance to high energy electromagnetic waves such as UV light and &ggr;-rays.
Abstract:
A quartz glass which would not become a source for the contamination even if it contains metallic impurities. This quartz glass includes a region where a concentration of E′ center as measured by means of an. electron spin resonance analysis is 3×1019 cm−3 or more. This quartz glass can be manufactured by a method including the steps of forming an initial quartz glass by melting and quenching a raw material for quartz glass, and implanting therein an ion, which is capable of entering into an SiO2 network of the initial quartz glass and substantially incapable of externally diffusing, to increase a concentration of E′ center in at least part of the initial quartz glass. This quartz glass can be manufactured by a method making use of a quartz glass raw material containing 0.01 to 0.1% by weight of-silicon, by a method of irradiating ultraviolet ray to the initial quartz glass, or by a method of giving an abrasion damage to the surface of the initial quartz glass by means of sand blast.
Abstract:
The invention relates to a process for the preparation of a quartz glass body comprising the process steps i.) Providing a silicon dioxide granulate, wherein the silicon dioxide granulate was made from pyrogenic silicon dioxide powder and the silicon dioxide granulate has a BET surface area in a range from 20 to 40 m2/g, ii.) Making a glass melt out of silicon dioxide granulate in an oven and iii.) Making a quartz glass body out of at least part of the glass melt, wherein the oven has at least a first and a further chamber connected to one another via a passage, wherein the temperature in the first chamber is lower than the temperature in the further chambers. The invention further relates to a quartz glass body which is obtainable by this process. The invention further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing of the quartz glass body.
Abstract:
To provide a black synthetic quartz glass with a transparent layer, which has high emissivity in the far infrared region, has excellent light-shielding properties, maintains the same degree of purity as synthetic quartz glass in terms of metal impurities, has high-temperature viscosity characteristics comparable to natural quartz glass, can undergo high-temperature processing like welding, and does not release carbon from its surface; together with a method for the production thereof.A porous silica glass body containing hydroxyl groups is subjected to a gas phase reaction in a volatile organosilicon compound atmosphere at a temperature between 100° C. and 1200° C. and, following the reaction, evacuation is commenced and, on reaching a degree of vacuum exceeding 10 mmHg (1343 Pa), heating is carried out at a temperature between 1200° C. and 2000° C. to produce a compact glass body.
Abstract:
First of all, there is provided a production process of a synthetic quartz glass which has less impurity, has a high-temperature viscosity characteristic equal to or more than that of a natural quartz glass, and hardly deforms even in a high-temperature environment, and especially a production process of a highly heat resistant synthetic quartz glass which is free from the generation of bubbles and is dense. Secondly, there is provided a highly heat resistant synthetic quartz glass body which is easily obtained by the production process of the present invention, and especially a transparent or black quartz glass body which is free from the generation of bubbles, is dense, has high infrared absorption rate and emission rate, and has an extremely high effect for preventing diffusion of alkali metal. The process is a process of producing a highly heat resistant quartz glass body having an absorption coefficient at 245 nm of 0.05 cm−1 or more, and the silica porous body was subjected to a reduction treatment, followed by baking, thereby forming a dense glass body.
Abstract:
The present invention relates to increasing the photosensitivity of optical fibers. One aspect of the present invention comprises a method for rapidly diffusing hydrogen or deuterium into an optical fiber from a gas mixture having a low total hydrogen content to generate changes in the refractive index of the optical fiber. The resulting photosensitive fiber may be used to create optical devices including Bragg gratings and Bragg grating-based devices.
Abstract:
A method is provided for manufacturing a synthetic silica glass. The method includes the steps of emitting an oxygen containing gas and a hydrogen containing gas from a burner; emitting a mixture of an organic silicon compound and a halogen compound from the burner; and reacting the mixture with the oxygen containing gas and the hydrogen containing gas to synthesize the silica glass.
Abstract:
In a known process for the production of opaque quartz glass a blank is formed from synthetic SiO2 granulate and is heated at a vitrification temperature to form a body of opaque quartz glass. In order to provide on this basis a process for the production of pure opaque quartz glass with a homogenous pore distribution, high density, high viscosity and a low tendency to devitrify, it is proposed according to the invention that the SiO2 granulate to be used is a SiO2 granulate (21; 31) composed of at least partially porous agglomerates of SiO2 primary particles, with a specific BET surface ranging from 1.5 m2/g to 40 m2/g and an apparent density of at least 0.8 g/cm3. A SiO2 granulate (21; 31) suitable for the implementation of the process is distinguished in that it is formed from at least partially porous agglomerates of SiO2 primary particles and in that it has a specific BET surface ranging from 1.5 m2/g to 40 m2/g and an apparent density of at least 0.6 g/cm3.