Abstract:
The invention concerns a Photonic Crystal Fiber (PCF) a method of its production and a supercontinuum light source comprising such PCF. The PCF has a longitudinal axis and comprises a core extending along the length of said longitudinal axis and a cladding region surrounding the core. At least the cladding region comprises a plurality of microstructures in the form of inclusions extending along the longitudinal axis of the PCF in at least a microstructured length section. In at least a degradation resistant length section of the microstructured length section the PCF comprises hydrogen and/or deuterium. In at least the degradation resistant length section the PCF further comprises a main coating surrounding the cladding region, which main coating is hermetic for the hydrogen and/or deuterium at a temperature below Th, wherein Th is at least about 50° C., preferably 50° C.
Abstract:
An object of the present invention is to provide an artificial quartz member inhibited from suffering the decrease in transmittance in a laser light wavelength region which is caused by long-term irradiation with a laser light having a wavelength of 200 nm or shorter; and a process for producing the artificial quartz member. The invention provides an artificial quartz member for use as an optical element to be irradiated with a laser light having a wavelength of 200 nm or shorter, having an aluminum content of 200 ppb or lower.
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:
Use of a flame hydrolysis apparatus for preparing fumed silica particles or a plasma torch apparatus for sintering fumed silica particles to fused silica particles is capable of producing highly pure silica with non-silicon metal impurities less than 500 pb, when at least an inner nozzle is constructed of a silicon-containing material having a low level of non-silicon metal impurities. Preferably, all surfaces in the respective apparatus which contact silica are of similar construction. The silica contains a low level of impurities as produced, without requiring further purification.
Abstract:
High purity synthetic quartz glass particles are derived from alkali metal silicate and have a total amount of metal impurities content of at least 1 nullg/g and, in particular, have oxygen-deficient defects. The high-purity synthetic quartz glass particles having high viscosity similar to natural quartz and high-purity similar to known synthetic quartz can be provided at a low cost.
Abstract:
Composite material with high resistance to temperature changes and a high density, and having an SiO2-containing matrix with quartz glass grains embedded therein is produced by preparing a suspension from a particle mixture of finely divided SiO2 powder having at least two different particle fractions and of the quartz glass grains, forming a green compact and sintering the compact. The matrix has an SiO2 content of at least 99% by wt. and is formed from at least first and second particle fractions, each of which is present as granules of nanoscale, amorphous, synthetically produced SiO2 primary particles having a mean primary particle size of less than 100 nm. The composite material has an SiO2-containing matrix with an SiO2 content of at least 99% by wt. It is particularly suited for applications such as starting material for producing a permanent mold for melting solar silicon.
Abstract:
Known is a method of producing a composite material having an SiO2-containing matrix in which quartz glass grains are embedded, wherein a suspension is prepared from a particle mixture of finely divided SiO2 powder having at least two different particle fractions and of the quartz glass grains, a green compact is formed therefrom and said compact is sintered. To permit an inexpensive production of a composite material having a high resistance to temperature changes together with a high density, it is suggested according to the invention that the matrix should have an SiO2 content of at least 99% by wt. and should be formed from at least a first (33) and a second (35) particle fraction, each of the particle fractions being present as granules of nanoscale, amorphous, synthetically produced SiO2 primary particles (2) having a mean primary particle size of less than 100 nm. The composite material produced according to the method is characterized by an SiO2-containing matrix which has an SiO2 content of at least 99% by wt. It is particularly suited for applications where temperature strength, density and high purity are of importance, e.g. as a starting material for producing a permanent mold for melting solar silicon.
Abstract:
In order to provide a quartz glass crucible distinguished by high purity, high opacity and/or low transmissibility in the IR spectrum, it is proposed on the basis of a known quartz glass crucible of opaque quartz glass with a crucible body symmetrical in relation to a rotational axis, an outer zone (3) of opaque quartz glass transitioning radially toward the inside into an inner zone (2) of transparent quartz glass and with a density of at least 2.15 g/cm3, that according to the invention, the crucible body (1) be made of a synthetic SiO2 granulate with a specific BET surface ranging from 0.5 m2/g to 40 m2/g, a tamped volume of at least 0.8 g/cm3 and produced from at least partially porous agglomerates of SiO2 primary particles. A process for producing a quartz glass crucible of this kind is distinguished according to the invention in that for the production of the crucible a SiO2 granulate is used which was formed from at least partially porous agglomerates of synthetically manufactured SiO2 primary particles and that it has a specific BET surface ranging from 0.5 m2/g to 40 m2/g and a tamped volume of at least 0.8 g/cm3, the heating effected in such a way that a vitrification front advances from the inside outward while an inner zone (4) of transparent quartz glass is being formed.
Abstract translation:为了提供在IR光谱中具有高纯度,高不透明性和/或低透射率的石英玻璃坩埚,提出了在已知的不透明石英玻璃的石英玻璃坩埚的基础上,坩埚体相对于 旋转轴线,不透明石英玻璃的外部区域(3),径向朝向内部转变成透明石英玻璃的内部区域(2),密度为至少2.15g / cm 3,根据本发明,坩埚体 (1)由具有0.5m 2 / g至40m 2 / g的比BET表面的合成SiO 2颗粒制成,捣实体积至少为0.8g / cm 3并由SiO 2一次颗粒的至少部分多孔的附聚物制成。 根据本发明,制造这种石英玻璃坩埚的方法的不同之处在于,对于坩埚的制造,使用由至少部分多孔的合成SiO 2原生颗粒的聚集体形成的SiO 2颗粒,并且其具有 比表面积为0.5m2 / g〜40m2 / g,捣实体积为0.8g / cm 3以上,使玻璃化前沿从内侧向前方前进,同时将内部区域(4) 正在形成透明的石英玻璃。
Abstract:
An improved sol-gel process is disclosed for producing a synthetic silica glass article, in which a sol is formed having a silica loading as high as 34 to 40%. This high loading is achieved by introducing an aqueous colloidal silica suspension into a silicon alkoxide solution and slowly stirring the mixture together, during which time the mixture hydrolyzes and the colloidal suspension is broken down by chemical reaction. This produces a hydrolyzed sol incorporating a suspension of very fine aggregates of colloidal particles, having particle sizes less than about 10 microns. The need for a stabilizing agent and/or continuous ultra-sonicating or violently stirring the sol is eliminated.