Abstract: An apparatus and method for manufacturing glass containers handles the containers individually after a hot forming process and annealing to prevent glass-to-glass contact. By handling the containers individually and preventing glass-to-glass contact damage to the containers in the form of checks and scratches is avoided. To prevent contact of the containers and damage arising from the contact, the equipment including conveyors, pushers, starwheels, shuttles, and transfer heads that move the glass containers through the apparatus maintains the glass containers in uniform spaced relationship at each stage of container processing until the containers are packaged.

Abstract: A method of forming a glass sheet comprises: (a) forming a ribbon of glass from molten glass with a pair of forming rollers; (b) reducing horizontal temperature variability of the ribbon of glass to be 10° C. or less across 80 percent of an entire width of the ribbon of glass before the ribbon of glass cools to a glass transition temperature; (c) controlling a cooling rate of the ribbon of glass while the ribbon of glass moves vertically downward within a setting zone such that the ribbon of glass has a first average cooling rate before the ribbon of glass cools to the glass transition temperature and a second average cooling rate after the ribbon of glass cools to the glass transition temperature, the first average cooling rate being less than the second average cooling rate; and (d) separating a glass sheet from the ribbon of glass.

Abstract: The present invention provides a method for producing a polishing composition which can polish an object to be polished at a high polishing speed and with fewer scratches (defects). The present invention is a method for producing a polishing composition, the method including: preparing silica in which an intensity of a peak of a silica four-membered ring structure and an intensity of a peak derived from a silica random network structure when analyzed by Raman spectroscopy satisfy a predetermined requirement; and mixing the silica with a dispersing medium.

Abstract: According to one embodiment, a method for thermally treating glass articles may include holding a glass article at a treatment temperature equal to an annealing temperature of the glass article ±15° C. for a holding time greater than or equal to 5 minutes. Thereafter, the glass article may be cooled from the treatment temperature through a strain point of the glass article at a first cooling rate CR1 less than 0° C./min and greater than ?20° C./min such that a density of the glass article is greater than or equal to 0.003 g/cc after cooling. The glass article is subsequently cooled from below the strain point at a second cooling rate CR2, wherein |CR2|>|CR1|.

Abstract: A method for heat treating a synthetic quartz glass having a hydroxyl concentration with a maximum/minimum difference (?OH) of less than 350 ppm involves the steps of first heat treatment of holding at 1,150-1,060° C. for a time of 0.5-10 hours, cooling down to a second heat treatment temperature at a rate of ?7° C./hr to ?30° C./hr, second heat treatment of holding at 1,030-950° C. for a time of 5-20 hours, and annealing at a rate of ?25° C./hr to ?85° C./hr. Two stages of heat treatment ensures that the glass has a low birefringence.

Abstract: A glass sheet cutting device fuses and divides a glass substrate using a preset cutting line as a boundary while supplying an assist gas and a laser beam from above the glass substrate along the preset cutting line of the glass substrate. The glass sheet cutting device includes a first laser irradiator for radiating a fusing laser beam and a second laser irradiator for radiating an annealing laser beam. Through a fusing gap formed between fused end surfaces by fusing, the second laser irradiator radiates the annealing laser beam obliquely from above onto the fused end surface to be annealed.

Abstract: Silica-titania glasses with small temperature variations in coefficient of thermal expansion over a wide range of zero-crossover temperatures and methods for making the glasses. The method includes a cooling protocol with controlled anneals over two different temperature regimes. A higher temperature controlled anneal may occur over a temperature interval from 750° C.-950° C. or a sub-interval thereof. A lower temperature controlled anneal may occur over a temperature interval from 650° C.-875° C. or a sub-interval thereof. The controlled anneals permit independent control over CTE slope and Tzc of silica-titania glasses. The independent control provides CTE slope and Tzc values for silica-titania glasses of fixed composition over ranges heretofore possible only through variations in composition.

Abstract: A method for annealing a glass disk is disclosed. The glass disk is placed on a base, whereby the bottom surface of the glass disk makes a contact with the base, and the top surface of the glass disk is exposed to air. The glass disk is heated with thermal energy supplied to the glass disk, the thermal energy comprising first thermal energy supplied from the air through the top surface and second thermal energy supplied from the base through the bottom surface.

Abstract: Disclosed is an apparatus and method for heat treating glass sheets, and in particular for heat treating very thing glass sheets arranged in closely spaced stacks. The glass sheets are positioned on a moving belt such that their major surfaces are substantially perpendicular to a direction of belt travel through the apparatus to aid in producing a uniform temperature profile within the glass sheets. The apparatus comprises air curtains positioned at the inlet and outlet of the apparatus to minimize the ingress of particulate into the apparatus. A reduced velocity of heated air flow within a lower portion of the apparatus relative to a velocity of the heated air in an upper portion of the apparatus causes particulate to drop out of the lower portion air flow. A rotating brush and vacuums positioned adjacent a lower portion of the belt assist in removing particulate from the moving belt.

Abstract: A method for processing a coated glass substrate may include a high-temperature activation process.

Abstract: Methods for processing glass using select wavelength radiation in a convective environment, broadly referred to as “Local Temporary Annealing”, “LASER Edge Strengthening” and “LASER Enhanced Thermal Strengthening.” Local Temporary Annealing allows strengthened glass to be brought to a neutral stress state so daughter units can be cut from strengthened glass and other processes usually only performed on annealed glass. LASER Edge Strengthening allows surface compression to be thermally imparted to the edges of a whole sheet or daughter units cut from annealed glass, or modification of residual edge stress profiles in strengthened glass to produce stable, strengthened edges. LASER Enhanced Thermal Strengthening allows surface compression to be imparted to a sheet of annealed glass whilst maintaining reduced surface temperatures so the glass has superior geometric stability and surface compression can be imparted at levels not conventionally possible.

Abstract: Surface modification layers and associated heat treatments, that may be provided on a sheet, a carrier, or both, to control both room-temperature van der Waals (and/or hydrogen) bonding and high temperature covalent bonding between the thin sheet and carrier. The room-temperature bonding is controlled so as to be sufficient to hold the thin sheet and carrier together during vacuum processing, wet processing, and/or ultrasonic cleaning processing, for example. And at the same time, the high temperature covalent bonding is controlled so as to prevent a permanent bond between the thin sheet and carrier during high temperature processing, as well as maintain a sufficient bond to prevent delamination during high temperature processing.

Abstract: The disclosure describes a method by which the Tzc of a silica-titania glass article, for example, a EUVL mirror substrate, can be tuned to within a specification range by means of a selected final anneal that shifts Tzc of the article or substrate to the desired Tzc value. In addition, since different mirrors in a set can be specified at different values of Tzc, this process can be on used glass samples or pieces from a single glass boule to make parts with different Tzc values, thus reducing the number of separate boules required to fill an order.

Abstract: [Problem] The provision of a synthetic quartz glass heat treatment method that can, by a single heat treatment, and without particular limitations on the OH group concentration distribution of the starting material, regulate the birefringence fast axis direction in the synthetic quartz glass after it has been heat-treated. [Means of Overcoming the Problem] A heat treatment method for synthetic quartz glass whereby columnar synthetic quartz glass having two opposing end faces and a lateral face is heat-treated covered with thermal insulator; wherein said heat treatment is performed using as end face thermal insulator which covers said two end faces, and as lateral face thermal insulator which covers said lateral face, thermal insulators that differ in at least either type or thickness to afford different thermal insulation effects such that the birefringence fast axis direction of said synthetic quartz glass is regulated.

Abstract: An optical ceramic material heat treatment apparatus, comprising: a furnace body that is capable to contain an optical ceramic material to be heat treated in the inside thereof; a temperature drop control heater that generates heat during dropping a temperature of the optical ceramic material; a refrigerant intake unit that introduces a refrigerant into the inside of the furnace body to flow the refrigerant therein; and a control unit that controls the temperature drop rate, wherein the temperature drop control heater is arranged in the inside of the furnace body and/or in the refrigerant intake unit, the control unit controls at least one of an amount of heat generation of the temperature drop control heater, and a flow rate of the refrigerant in the inside of the furnace body to control a temperature drop rate at the optical ceramic material or in the vicinity thereof to be kept in a predetermined profile.

Abstract: A nozzle housing assembly, which is used in a convection heating furnace for a heat treatable glass sheet. The nozzle housing assembly comprises an elongated enclosure, at least one elongated heating resistance in the enclosure for heating convection air, and orifices in a bottom surface of the enclosure for blasting heated convection air against the glass sheet. The enclosure is divided with a flow-throttling partition into a top supply duct and a bottom nozzle box, the heating resistances being housed in the latter. Flow-throttling openings present in the partition are positioned to comply with the location and shape of the heating resistances.

Abstract: A method of making a silica glass having a uniform fictive temperature. The glass article is heated at a target fictive temperature, or heated or cooled at a rate that is less than the rate of change of the fictive temperature, for a time that is sufficient to allow the fictive temperature of the glass to come within 3° C. of the target fictive temperature. The silica glass is then cooled from the target fictive temperature to a temperature below the strain point of the glass at a cooling rate that is greater than the relaxation rate of the glass at the target fictive temperature. The silica glass has a fictive temperature that varies by less than 3° C. after the annealing step. A silica glass made by the method is also described.

Abstract: The present invention relates to a process for production of a TiO2—SiO2 glass body, comprising a step of, when an annealing point of a TiO2—SiO2 glass body after transparent vitrification is taken as T1(° C.), holding the glass body after transparent vitrification in a temperature region of from T1?90(° C.) to T1?220(° C.) for 120 hours or more.

Abstract: An optical fiber apparatus is suitable to operate under irradiation, more particularly to mitigating the damage of a rare-earth-doped optical fiber element as part of an optical fiber assembly causes by irradiation. The irradiation mitigation attributes to a photo-annealing apparatus including at least a shorter wavelength photo-annealing spectral content, which is relative to that of a pump light source, for effectively photo-annealing the rare-earth-doped fiber element. Photo-annealing by such shorter wavelength light results in a fast and nearly complete recovery of radiation induced attenuation of the rare-earth-doped optical fiber element in the wavelength range from 900 nm to 1700 nm.

Abstract: A process for producing a synthetic silica glass optical component which contains at least 1×1017 molecules/cm3 and has an OH concentration of at most 200 ppm and substantially no reduction type defects, by treating a synthetic silica glass having a hydrogen molecule content of less than 1×1017 molecules/cm3 at a temperature of from 300 to 600° C. in a hydrogen gas-containing atmosphere at a pressure of from 2 to 30 atms.

Abstract: To provide a process to improve acid resistance of a glass substrate for an information recording medium. A process for producing a glass substrate for an information recording medium, comprising processing a glass formed into a plate by a float process, a down-draw method or a press method, wherein, in cooling of the glass in the last step where the glass has a temperature of at least its strain point, the time during which the glass temperature is at least its strain point and at most a temperature where the glass viscosity is 1010 dPa·s is at least 13 minutes.

Abstract: A mode-locked laser system operable at low temperature can include an annealed, frequency-conversion crystal and a housing to maintain an annealed condition of the crystal during standard operation at the low temperature. In one embodiment, the crystal can have an increased length. First beam shaping optics can be configured to focus a beam from a light source to an elliptical cross section at a beam waist located in or proximate to the crystal. A harmonic separation block can divide an output from the crystal into beams of different frequencies separated in space. In one embodiment, the mode-locked laser system can further include second beam shaping optics configured to convert an elliptical cross section of the desired frequency beam into a beam with a desired aspect ratio, such as a circular cross section.

Abstract: A method for improving the thermo-mechanical properties of an aluminum-titanate composite, the composite including at least one of strontium-feldspar, mullite, cordierite, or a combination thereof, including: combining a glass source and an aluminum-titanate source into a batch composition; and firing the combined batch composite composition to produce the aluminum-titanate composite. Another method for improving the thermo-mechanical properties of the composite dips a fired composite article into phosphoric acid, and then anneal the dipped composite article. The resulting composites have a thin glass film situated between the ceramic granules of the composite, which can arrest microcrack propagation.

Abstract: A method for manufacturing glass hard disk substrates comprises annealing and then tempering previously formed glass hard disk substrates. The annealed and tempered glass hard disk substrates have improved strength and stress resistance without chemical treatments.

Abstract: A method and an apparatus for annealing a glass sheet, which can sufficiently reduce ITT formed in the glass sheet, are provided. In the method for annealing a glass sheet G of the present invention, in a state that a heated and bent glass sheet G is placed on a forming mold 16, first, a region of the glass sheet G to be lifted up is cooled by cooling devices 20, 22, to make the temperature of the region to be lifted up to be a temperature of at most the strain point. Next, in this state, a lift-up member 36 is operated to lift up the region of the glass sheet G to be lifted up, by rods 38, 38 . . . , to separate the glass sheet G from the forming mold 16.

Abstract: The invention relates to a process for making a SiO2—RExOy—Al2O3 glass comprising preparing a glass according to a conventional process wherein the conventional process comprises a step of heat treating a mixture of SiO2, RExOy, and Al2O3 at a temperature greater than the spinodal temperature for 0.1 to 10 hours wherein RExOy is a rare earth oxide and RE is a rare earth element chosen from Sc, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and combinations thereof. The invention also relates to glasses prepared by the process and glass lasers, optical amplifiers and laminated glass that comprise the glass prepared by the process.

Abstract: A fused silica glass article having a low absolute refractive index and low concentrations of hydroxyl groups, halogens, and metal having a low absolute refractive index. The glass article contains less than about 10 ppm protium-containing and deuterium-containing hydroxyl groups by weight and less than about 20 ppm halogens by weight. The silica glass article also has an absolute refractive index (ARI) less than or equal to 1.560820. In one embodiment, the ARI of the fused silica article is achieved by lowering the fictive temperature of the fused silica. A method of lowering the fictive temperature is also described.

Abstract: The present invention provides a synthetic silica glass for an optical member in which not only a fast axis direction in an optical axis direction is controlled, and a birefringence in an off-axis direction is reduced, but a magnitude of a birefringence in the optical axis direction is controlled to an arbitrary value, such that an average value of a value BR cos 2?xy defined from a birefringence BR and a fast axis direction ?xy as measured from a parallel direction to the principal optical axis direction is defined as an average birefringence AveBR cos 2?xy, and when a maximum value of a birefringence measured from a vertical direction to the principal optical axis direction of the optical member is defined as a maximum birefringence BRmax in an off-axis direction, the following expression (1-1) and expression (2-1) are established: ?1.0?AveBR cos 2?xy<0.0??(1-1) 0.0?BRmax?1.0??(2-1).

Abstract: Method of identifying a container (1) obtained by a process comprising the following steps: (A) starting from a blank (2) of the container (1), at least part of the said container (1) is formed; (B) a two-dimensional or three-dimensional marking zone (4), the temperature of which is maintained at a value below the glass transformation temperature of the constituent substrate, is provided in or on the substrate of the blank (2) and, in the said marking zone (4), an identification code (5) is reproduced by illumination (6) of the said marking zone (4) with at least one beam (7) of coherent monochromatic localized electromagnetic radiation to which the substrate is at least partially transparent, the said beam (7) being operated and controlled in order to remove or modify the constituent substrate of the wall (3) and to leave the identification code (5), in positive or negative form, in the said wall so that the said code is readable; and (C) at least the said marking zone (4) is annealed so as at least to reduc

Abstract: The present invention relates to a process for production of a TiO2—SiO2 glass body, comprising a step of, when an annealing point of a TiO2—SiO2 glass body after transparent vitrification is taken as T1(° C.), holding the glass body after transparent vitrification in a temperature region of from T1?90(° C.) to T1?220(° C.) for 120 hours or more.

Abstract: The present invention relates to a process for production of a TiO2—SiO2 glass body, comprising: a step of, when an annealing point of a TiO2—SiO2 glass body after transparent vitrification is taken as T1 (° C.), heating the glass body after transparent vitrification at a temperature of T1+400° C. or more for 20 hours or more; and a step of cooling the glass body after the heating step up to T1?400 (° C.) from T1 (° C.) in an average temperature decreasing rate of 10° C./hr or less.

Abstract: A method for processing a coated glass substrate may include a high-temperature activation process.

Abstract: The present invention is to provide a TiO2—SiO2 glass whose coefficient of linear thermal expansion at the time of irradiating with high EUV energy light becomes substantially zero when used as an optical member of an exposure tool for EUVL. The present invention relates to a TiO2-containing silica glass, having a fictive temperature of 1,000° C. or lower, a OH concentration of 600 ppm or higher, a temperature at which the coefficient of linear thermal expansion becomes 0 ppb/° C. of from 40 to 110° C., and an average coefficient of linear thermal expansion in the temperature range of 20 to 100° C., of 50 ppb/° C. or lower.

Abstract: A method of making a fused silica article having a combined concentration of protium and deuterium in a range from about 1×1016 molecules/cm3 up to about 6×1019 molecules/cm3. In some embodiments, deuterium is present in an amount greater than its natural isotopic abundance. The method includes the steps of providing a fused silica boule, diffusing at least one of protium and deuterium into the boule, and annealing the boule to form the fused silica article. A method of diffusing hydrogen into fused silica and a fused silica article loaded with hydrogen formed by the method are also described.

Abstract: To optimize an optical component of synthetic quartz glass, in the case of which a quartz glass blank is subjected to a multistage annealing treatment, with respect to compaction and central birefringence, the present invention suggests a method comprising the following steps: (a) a first treatment phase during which the quartz glass blank is treated in an upper temperature range between 1130° C. and 1240° C., (b) cooling the quartz glass blank at a first-higher-mean cooling rate to a quenching temperature below 1100° C., a fictive temperature with a high mean value of 1100° C. or more being reached in the quartz glass, (c) a second treatment phase which comprises cooling of the quartz glass blank at a second-lower-mean cooling rate, and in which the quartz glass blank is treated in a lower temperature range between 950° C. and 1100° C. such that a fictive temperature is reached in the quartz glass with a low mean value which is at least 50° C.

Abstract: When a synthetic quartz glass substrate is prepared from a synthetic quartz glass block, (I) the block has a hydrogen molecule concentration of 5×1017-1×1019 molecules/cm3, (II) the substrate has a hydrogen molecule concentration of 5×1015-5×1017 molecules/cm3, (III) the substrate has an in-plane variation of its internal transmittance at 193.4 nm which is up to 0.2%, and (IV) the substrate has an internal transmittance of at least 99.6% at 193.4 nm. The synthetic quartz glass substrate has a high transmittance and a uniform transmittance distribution, and is adapted for use with excimer lasers, particularly ArF excimer lasers.

Abstract: To provide a process to improve acid resistance of a glass substrate for an information recording medium. A process for producing a glass substrate for an information recording medium, comprising processing a glass formed into a plate by a float process, a down-draw method or a press method, wherein, in cooling of the glass in the last step where the glass has a temperature of at least its strain point, the time during which the glass temperature is at least its strain point and at most a temperature where the glass viscosity is 1010 dPa·s is at least 13 minutes.

Abstract: A method of making a silica glass having a uniform fictive temperature. The glass article is heated at a target fictive temperature, or heated or cooled at a rate that is less than the rate of change of the fictive temperature, for a time that is sufficient to allow the fictive temperature of the glass to come within 3° C. of the target fictive temperature. The silica glass is then cooled from the target fictive temperature to a temperature below the strain point of the glass at a cooling rate that is greater than the relaxation rate of the glass at the target fictive temperature. The silica glass has a fictive temperature that varies by less than 3° C. after the annealing step. A silica glass made by the method is also described.

Abstract: The disclosure describes a method by which the Tzc of a silica-titania glass article, for example, a EUVL mirror substrate, can be tuned to within a specification range by means of a selected final anneal that shifts Tzc of the article or substrate to the desired Tzc value. In addition, since different mirrors in a set can be specified at different values of Tzc, this process can be on used glass samples or pieces from a single glass boule to make parts with different Tzc values, thus reducing the number of separate boules required to fill an order.

Abstract: The invention relates to a device for forming aerosol, the device comprising at least one gas-dispersing atomizer for atomizing a liquid into aerosol by means of gas at an atomizing head of the atomizer and an atomizing chamber, which is in flow connection with the atomizing head and in which flow restraints are arranged for changing the hydrodynamic properties of the aerosol flow discharging from the atomizing head. According to the present invention the flow restraints are arranged in the inner walls of the atomizing chamber in such a manner that they protrude from the inner walls to the inside of the atomizing chamber.

Abstract: A synthetic quartz glass substrate having (i) an OH concentration of 1-100 ppm and a hydrogen molecule concentration of 1×1016-1×1019 molecules/cm3, (ii) an in-plane variation of its internal transmission at wavelength 193.4 nm which is up to 0.2%, and (iii) an internal transmission of at least 99.6% at wavelength 193.4 nm is suited for use with excimer lasers.

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: A process for making glass sheet with low compaction suitable for high temperature applications, such as low-temperature polysilicon-based TFT displays, and glass sheets thus made. The glass sheet desirably has an anneal point of at least 765° C., a CTE at most 42×10?7/° C. The process involves cooling the glass melt form a temperature corresponding to a viscosity of 1.0×1010 poise to a temperature corresponding to a viscosity of 1.0×1015 poise at a cooling rate CR, where CR?5° C./second. The absolute value of the measured compaction of the glass sheet desirably is at most 175 ppm upon being re-heated to 675° C. for a period of time.

Abstract: A method of making a fused silica article having a combined concentration of protium and deuterium in a range from about 1×1016 molecules/cm3 up to about 6×1019 molecules/cm3. In some embodiments, deuterium is present in an amount greater than its natural isotopic abundance. The method includes the steps of providing a fused silica boule, diffusing at least one of protium and deuterium into the boule, and annealing the boule to form the fused silica article. A method of diffusing hydrogen into fused silica and a fused silica article loaded with hydrogen formed by the method are also described.

Abstract: There are provided glass-ceramics comprising, in mass %, 50-60% SiO2, 22-26% Al2O3 and 3-5% Li2O, having an average crystal grain diameter exceeding 100 nm, and having an average linear thermal expansion coefficient of 30×10?7/° C. or below within a temperature range of 0° C. to 50° C. These glass-ceramics are manufactured by a step of melting glass raw materials, a step of forming the molten glass, a step of annealing the formed glass, a first heat treating step for heat treating the annealed glass at a temperature of 650-750° C. for 0.1 hour to 200 hours, and a second heat treating step for heat treating the glass at a temperature of 800-1000° C. for 0.1 hour to 50 hours.

Abstract: To optimize an optical component of synthetic quartz glass, in the case of which a quartz glass blank is subjected to a multistage annealing treatment, with respect to compaction and central birefringence, the present invention suggests a method comprising the following steps: (a) a first treatment phase during which the quartz glass blank is treated in an upper temperature range between 1130° C. and 1240° C., (b) cooling the quartz glass blank at a first-higher-mean cooling rate to a quenching temperature below 1100° C., a fictive temperature with a high mean value of 1100° C. or more being reached in the quartz glass, (c) a second treatment phase which comprises cooling of the quartz glass blank at a second-lower-mean cooling rate, and in which the quartz glass blank is treated in a lower temperature range between 950° C. and 1100° C. such that a fictive temperature is reached in the quartz glass with a low mean value which is at least 50° C.

Abstract: A convection compatible closed cassette and method are described herein where the closed cassette is used to heat treat (compact) one or more glass sheets in a uniform manner and in a clean environment. In the preferred embodiment, the closed cassette includes multiple enclosed sections that are supported by a mounting structure in a manner where there is an open passageway between the major surfaces of each pair of the supported enclosed sections. And, each enclosed section is designed to hold and support multiple glass sheets in a manner where there is a space between the major surfaces of each pair of the supported glass sheets. In operation, the closed cassette is placed into an oven (e.g., lehr, batch kiln) so that hot/cold unfiltered air can flow across the major surfaces of each enclosed section and uniformly heat/cool the enclosed glass sheets.

Abstract: In a process for producing an air-quench-toughened glass plate, defective glass plates containing nickel sulfide (NiS) are removed by compulsory breaking the glass plates. Such compulsory breakage is carried out in the course of a batch-manner soaking process carried out after a toughening step; in the course of a toughening step carried out after generation of cracks in an annealing step; in the course of a toughening step carried out after generation of cracks in a pretreatment step; or in the course of a continuous annealing step carried out after a toughening step. Through the method, NiS-free toughened glass plates of high-quality can be produced.

Abstract: A method of fabricating a glass sheet comprises modifying the thermal stress in the glass such that it is a tensile stress or substantially zero stress in a particular temperature zone of the glass, with that zone selected such that the glass sheet is formed substantially free of warping. In an example embodiment, the modifying of the thermal stress is effected by non-uniform cooling of the glass across the glass transition temperature range. This non-uniform cooling may be applied in cooling segments that are linear and at least two of the segments have differing slope.

Abstract: The invention relates to the loading of quartz glass objects with hydrogen in an annealing process in a furnace for improving the homogeneity of the refractive index and the laser resistance while, at the same time, maintaining a specified stress birefringence of each of the glass objects. Initially, the distribution of the refractive index, the stress birefringence, the distribution of the hydrogen and the differences in refractive index, which are to the equalized, are determined in the respective glass object, after which the hydrogen change, which is necessary for equalizing the refractive index, is determined. Furthermore, the annealing temperature and its holding time, as well as the hydrogen concentration and the hydrogen pressure in the furnace are adjusted to achieve a sufficiently equalized distribution of refractive index.