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 crucible is made in a mold cavity of the type in which ambient atmosphere can be drawn through silica grain in the cavity. In one embodiment, a silica grain layer is formed in the mold cavity and gas, which may comprise helium, nitrogen, hydrogen, or a mixture thereof, is introduced into the mold cavity. The silica grain layer is heated while substantially no ambient atmosphere is drawn through the silica grain. Thereafter, at least a portion of the silica grain layer is fused while drawing ambient atmosphere through the silica grain. The gas displaces air in the mold cavity thereby reducing nitrogen oxides and ozone.

Abstract: Methods for producing a quartz glass component with reflector layer are known in which a reflector layer composed of quartz glass acting as a diffuse reflector is produced on at least part of the surface of a substrate body composed of quartz glass. In order, taking this as a departure point, to specify a method which enables cost-effective and reproducible production of uniform SiO2 reflector layers on quartz glass components, it is proposed according to the invention that the reflector layer is produced by thermal spraying by means of SiO2 particles being fed to an energy carrier, being incipiently melted or melted by means of said energy carrier and being deposited on the substrate body. In the case of a quartz glass component obtained according to the method, the SiO2 reflector layer is formed as a layer which is produced by thermal spraying and has an opaque effect and which is distinguished by freedom from cracks and uniformity.

Abstract: In a known method for drawing a tubular quartz glass strand, SiO2-containing starting material is fed to a melting crucible, softened therein into a viscous quartz glass mass (27), and said mass is pulled vertically downward as a cylindrical quartz glass strand (5; 33) through a die (4; 34) provided in the bottom region of the melting crucible (1), said die having a gap-shaped outlet (25; 36), which is defined by a bottom opening and a die inside part, and thereafter the quartz glass cylinder is cut to length.

Abstract: In a known method for bonding components made of material with a high silicic acid content by means of a substance to substance bond, a SiO2-containing bonding mass is formed between connecting surfaces of the components. In order to provide for cost-efficient manufacture of a thermally stable composite, the invention proposes to generate a SiO2-containing bonding mass that is generic with regard to the material with a high silicic acid content, comprising the following procedural steps: provision of a slurry containing amorphous SiO2 particles; formation of a slurry mass between the connecting surfaces which are fixed in position with regard to each other; drying of the slurry mass; and solidification of the slurry mass by heating under formation of the SiO2-containing bonding mass. A component assembly manufactured according to the method of the invention shows high temperature resistance and thermal fatigue resistance and can also be used in contamination-sensitive applications.

Abstract: The invention relates to a known method for the production of a cylinder from quartz glass, comprising a step, wherein an SiO2 body which comprises a porous SiO2 soot layer and has a lower end, an upper end, and an outer casing, is sintered to form said quartz glass cylinder in a vitrification furnace, and is being held in a vertical orientation by means of a retaining device, which comprises an upper retaining element connected at the upper end of the SiO2 body, and a lower retaining element disposed on the lower end. In order to provide a method based thereon, by means of which even heavy bodies made of porous SiO2 can be safely retained during vitrification, the invention provides that the retaining device has a dimensionally stable connecting part, which extends inside the vitrification furnace along the outer casing of the SiO2 body and which connects the upper and the lower retaining elements to each other.

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: According to a known vertical drawing method for producing a cylindrical glass body, the cylinder longitudinal axis of the glass cylinder is adjusted by hand in relation to the longitudinal axis of a heating tube. The aim of the invention is to optimize the stability of said glass body.

Abstract: The production of an optical component from quartz glass by elongation of a coaxial arrangement of a core rod and a hollow cylinder is known. The arrangement is thus introduced into a heating zone, such that the lower end begins to partly soften and the component drawn from the softened part. According to the invention, a pseudo-continuous method for the formation of the restriction in the inner passage of the hollow cylinder on which the core rod is supported, is disclosed, whereby an upper hollow cylinder is fused end on with a lower hollow cylinder to form an axial composite cylinder, a core rod is introduced into the lower hollow cylinder and the axial cylinder composite partly softened and elongated to form the optical component.

Abstract: Known methods for producing a semifinished product for an optical component of synthetic quartz glass of high homogeneity require a great number of forming or shaping steps for homogenization, which is troublesome in terms of energy and time and entails the risk that impurities might be introduced.

Abstract: In a known method for producing a raised marking on a glass object, a suspension containing SiO2 particles is applied to a surface of the glass object as a pattern, and the pattern is compacted to form the marking. Starting from this, in order to enable a cost-effective production of an optically appealing and uniform marking on an object made of quartz glass, which marking is also suited for applications at high temperature or in a contamination-sensitive environment, such as in solar cell and semiconductor production, it is suggested according to the invention that a binder-free suspension be used to create a marking on a quartz glass object, the suspension containing a dispersion liquid and amorphous SiO2 particles having particle sizes of up to a maximum of 500 ?m, of which are between 0.2% by wt. and 15% by wt. SiO2 nanoparticles having particle sizes of less than 100 nm, and the solids content thereof, i.e.

Abstract: A known method for producing synthetic quartz glass comprises the method steps: (a) forming a cylindrical SiO2 soot body having an inner portion and at least one free cylinder jacket surface surrounding the inner portion; (b) thermally drying the porous soot body; and (c) vitrifying the dried soot body with formation of the cylinder from synthetic quartz glass.

Abstract: Known synthetic quartz glass tubes for the production of a preform have an inner bore with a surface layer produced without using tools in the molten state and an inner zone. The aim of the invention is to provide a tube which does not release any OH groups to the surroundings. For this purpose, the surface layer (30) has a thickness of 10 ?m and an average OH content of not more than 5 ppm by weight and an average surface roughness Ra of not more than 0.1 ?m. The inner zone (34) that starts on the surface layer (30) and terminates 10 ?m before the outer wall has an average OH content of not more than 0.2 ppm by weight. A simple and inexpensive method for producing a quartz tube of the above type is to continuously draw a tube strand from a softened quartz glass mass in a vertical drawing process. A scavenging gas is circulated through the inner bore of the tube, said gas having a water content of less than 100 ppb per weight.

Abstract: The invention relates to a method allowing cost-effective production of doped quartz glass, particularly laser-active quartz glass, that is improved with regard to the homogeneity of the doping material distribution, in that a suspension is provided comprising SiO2 particles and an initial compound for at least one doping material in an aqueous fluid, the fluid being removed under formation of a doped intermediate product comprising particles of the doping material or particles of the precursor substance or the doping material, and the doped quartz glass is formed by sintering the doped intermediate product, wherein at least part of the particles of the doping material or the particles of the precursor substance of the same is generated in the suspension as a precipitate of a pH-value-controlled precipitation reaction of the initial compound.

Abstract: In a known method for producing tubes of quartz glass, a hollow cylinder (2) of quartz glass is continuously supplied to a heating zone (1) and is softened therein in regions, and a tube strand (21) is drawn off at a drawing speed from the softened region with formation of a drawing bulb (26), and the tubes to be produced are cut to length in the form of tube strand pieces by separating the tube strand (21) at a desired separation point (T, Vu, Vo) and an internal pressure differing from the external pressure applied to the outer cladding is maintained in the inner bore (4) of the hollow cylinder (2) in that the inner bore (4) of the tube strand is provided with a flow obstacle.

Abstract: The invention starts from a known method for producing a glass body, comprising forming a cylindrical blank by successive deposition of a plurality of material layers on the outer surface of a substrate body which is rotating about its longitudinal axis, by using an arrangement of a plurality of depositors which are directed onto the substrate body and which are fed via supply lines with process media for material layer deposition and which are moved without a reversing movement relative to the longitudinal axis of the substrate body. Starting therefrom, to provide a method for producing a glass body of high homogeneity that can be realized in a constructionally simple way, the invention suggests that the movement of the depositor arrangement along the longitudinal axis of the substrate body should be accompanied by a displacement of the substrate body.

Abstract: In a known method for the production of a blank mold for optical fibers, a fluorine-doped SiO2 enveloping glass is produced on a core glass cylinder that rotates about its longitudinal axis, wherein a silicon-containing starting substance is fed to a plasma burner, said substance is then oxidized in a plasma flame assigned to the plasma burner to obtain SiO2 particles, the SiO2 particles are deposited by layers on the enveloping surface of the cylinder of the core glass cylinder in the presence of fluorine and sintered into the enveloping glass. The invention aims at providing an economical method, which builds upon the above-mentioned method, in order to produce a blank mold from which optical multi-mode fibers (52) can be obtained.

Abstract: An ideal quartz glass for a wafer jig for use in an environment having an etching effect is distinguished by both high purity and high resistance to dry etching. To indicate a quartz glass that substantially fulfills these requirements, it is suggested according to the invention that the quartz glass is doped with nitrogen at least in a near-surface area, has a mean content of metastable hydroxyl groups of less than 30 wt ppm and that its fictive temperature is below 1250° C. and its viscosity is at least 1013 dPa·s at a temperature of 1200° C. An economic method for producing such a quartz glass comprises the following method steps: melting an SiO2 raw material to obtain a quartz glass blank, the SiO2 raw material or the quartz glass blank being subjected to a dehydration measure, heating the SiO2 raw material or the quartz glass blank to a nitriding temperature in the range between 1050° C. and 1850° C.

Abstract: The invention relates to a method for interferometrically measuring large optics. A combination of a method known as stitching technique, during which the sub-interferograms are determined on partial surfaces of measuring area and are joined in a software-controlled manner and which, as a result, enables the use of small, more cost-effective interferometers, however polished surfaces of the test piece being assumed, together with an immersion method, during which, in fact, lower demands for the surface quality of the test piece exist that, however, is accompanied by edge faults. In order to make this combination possible, a modification of the stitching technique is developed, during which the measuring area (CA) is completely covered by a film consisting of an immersion liquid.

Abstract: The invention is concerned with a material which shows low absorption for UV radiation having a wavelength below 250 nm, low birefringence, high chemical resistance and high radiation resistance and which is therefore particularly usable for making optical components for microlithography. According to the invention the material consists of synthetically produced quartz crystallites which form a polycrystalline structure and have a mean grain size in the range between 500 nm and 30 ?m. The method according to the invention for making a blank from the material comprises providing granules consisting of synthetically produced quartz crystals having a mean grain size in the range between 500 nm and 30 ?m, and sintering the granules to obtain a blank of polycrystalline quartz.