One aspect relates to a process for the preparation of a quartz glass body. The process includes providing silicon dioxide particles, making a glass melt out of the silicon dioxide particles in an oven and making a quartz glass body out of at least part of the glass melt. The oven has a gas outlet through which gas is removed from the oven, wherein the dew point of the gas on exiting the oven through the gas outlet is less than 0° C. One aspect further relates to a quartz glass body which is obtainable by this process. One aspect further relates to a light guide, an illuminant and a formed body, which are each obtainable by further processing of the quartz glass body.

An optical component made of synthetic quartz glass includes a glass structure substantially free of oxygen defect sites and having a hydrogen content of 0.1×10.sup.16 to 1.0×10.sup.18 molecules/cm.sup.3, an SiH group content of less than 2×10.sup.17 molecules/cm.sup.3, a hydroxyl group content of 0.1 to 100 wt. ppm, and an Active temperature of less than 1070° C. The optical component undergoes a laser-induced change in the refractive index in response to irradiation by a radiation with a wavelength of 193 nm using 5×10.sup.9 pulses with a pulse width of 125 ns and a respective energy density of 500 μJ/cm.sup.2 at a pulse repetition frequency of 2000 Hz. The change totals a first measured value M.sub.193 nm when measured using the applied wavelength of 193 nm and a second measured value M.sub.633 nm when measured using a measured wavelength of 633 nm. The ratio M.sub.193 nm/M.sub.633 nm is less than 1.7.

A method for manufacturing an optical fiber preform including a core part and a cladding part is disclosed. The method includes: adding an alkali metal to an inner surface of a silica-based glass pipe; etching the inner surface of the silica-based glass pipe to which the alkali metal is added; making a glass rod by collapsing the silica-based glass pipe after the etching; and making an optical fiber preform using the glass rod. The silica-based glass pipe is heated in the adding such that a surface temperature of the silica-based glass pipe falls within a temperature range of 1500° C. or higher to lower than 2000° C.

Methods for selecting titania-doped quartz glass which experiences a reduction in OH group concentration of less than or equal to 100 ppm upon heat treatment at 900° C. for 100 hours as suitable material for the EUV lithography member.

A method for producing rod lenses with an enveloping diameter of the rod lens face of up to 200 mm and an edge length of at least 800 mm. The method is characterized in that fabrication is performed from a cylindrical rod lens element made from synthetic quartz glass material configured as a fused silica ingot. This is performed using a flame hydrolysis method with a direct one stage deposition process of SIO.sub.x particles from a flame stream onto die that rotates and is moveable in a linear manner with respect to the flame stream.

One aspect relates to a process for the preparation of a quartz glass body. The process includes providing a silicon dioxide granulate from a pyrogenically produced silicon dioxide powder, making a glass melt out of silicon dioxide granulate, and making a quartz glass body out of at least part of the glass melt. The size of the quartz glass body is reduced to obtain a quartz glass grain. The quartz glass body is processed to make a preform and an opaque quartz glass body is made from the preform. One aspect further relates to an opaque quartz glass body which is obtainable by this process. One aspect further relates to a reactor and an arrangement, which are each obtainable by further processing of the opaque quartz glass body.

Provided is a titanium-containing quartz glass having excellent UV absorption. The quartz glass absorbs ultraviolet rays having a wavelength of 250 nm or less, ozone generation-related adverse effects on the human body, are prevented, a decrease in transmittance of the quartz glass in the range from near-ultraviolet to visible light due to being colored when irradiated with ultraviolet rays does not occur, absorption build-up or lamp burst-inducing deformation build-up, which is caused by a structural change in the quartz glass that occurs in the range of 200-300 nm when irradiated with ultraviolet rays, is suppressed, and a decrease in transmittance at intended wavelength ranges does not occur even when exposed to ultraviolet rays. The titanium-containing quartz glass having excellent UV absorption is colorless, wherein the average concentration of titanium is 10-500 ppm, the concentration of OH group is 10-350 ppm.

A diffuser material of synthetically produced, pore-containing quartz glass and a method for the manufacture of a molded body consisting fully or in part thereof. The diffuser material has a chemical purity of at least 99.9% SiO.sub.2, a cristobalite content of not more than 1%, and a density in the range of 2.0 to 2.18 g/cm.sup.3. Starting therefrom, to indicate a diffuser material which is improved with respect to diffuse reflectivity with Lambertian behavior over a wide wavelength range, high material homogeneity and UV radiation resistance, the quartz glass has a hydroxyl group content in the range of at least 200 wt. ppm and at least 80% of the pores have a maximum pore dimension of less than 20 μm.

The invention relates to a process for preparing a quartz glass body comprising the process steps i.) Providing a silicon dioxide granulate, ii.) Making a glass melt from the silicon dioxide granulate in a melting crucible, and iii.) Making a quartz glass body from at least a part of the glass melt, wherein the melting crucible is comprised in an oven and is made of at least one material comprising tungsten or molybdenum or a combination thereof. The invention further relates to a quartz glass body which can be obtained by this process. Further, the invention relates to a light guide, an illuminant and a formed body, each of which can be obtained by processing the quartz glass body further.

A method for preparing a glass composite wavelength converter comprising the steps of providing at least one phosphor material, providing a powder of glass components, mixing the phosphor material and the powder of glass components, thereby preparing a first mixture, adding at least one oxidizing agent to the first mixture, mixing the oxidizing agent with the first mixture, thereby preparing a second mixture, applying pressure and current to the second mixture, thereby preparing a glass composite wavelength converter is described. Furthermore, a glass component wavelength converter and a light source are described.