Abstract: A process for the production of a fluorinated quartz glass including the steps of generating SiO2 particles in a synthesis burner; depositing the resulting SiO2 particles into a body; and vitrifying the resulting body, wherein a fluorinating agent having a boiling point greater than or equal to ?10° C. is supplied to the synthesis burner.

Abstract: A method for homogenizing glass includes the method: providing a cylindrical blank composed of the glass having a cylindrical outer surface that extends along a longitudinal axis of the blank between a first end face and a second end face, forming a shear zone in the blank by softening a longitudinal section of the blank and subjecting it to a thermal-mechanical intermixing treatment, and displacing the shear zone along the longitudinal axis of the blank. The displacement of the shear zone along the longitudinal axis of the blank is superimposed by a simultaneous oscillating motion of the shear zone along the longitudinal axis of the blank. The first end of the blank is rotated at a first rotational speed and the second end of the blank is rotated at a second rotational speed. An oscillating motion of the shear zone is generated by periodically varying the first and/or second rotational speed.

Abstract: In known methods for producing a glass component, a void-containing intermediate product containing doped or non-doped SiO2 is inserted into a sheath tube composed of glass, which has a longitudinal axis and an inner bore, and is thermally treated therein. In order to subject the intermediate product to a thermal and/or reactive treatment that is reproducible and uniform in its effect from this starting point, it is proposed in one embodiment that into the sheath tube's inner bore a first gas-permeable gas diffuser is inserted which is displaceable along the sheath tube's longitudinal axis and is pressed against the intermediate product during the thermal treatment.

Abstract: A method for homogenizing glass includes the method: providing a cylindrical blank composed of the glass having a cylindrical outer surface that extends along a longitudinal axis of the blank between a first end face and a second end face, forming a shear zone in the blank by softening a longitudinal section of the blank and subjecting it to a thermal-mechanical intermixing treatment, and displacing the shear zone along the longitudinal axis of the blank. To enable a radial mixing within the shear zone in addition to the tangential mixing with the lowest possible time and energy input, starting from this method, cylindrical sections of the blank are adjacent to the shear zone on both sides, the first cylindrical section having a first central axis and the second cylindrical section having a second central axis, the first central axis and the second central axis being temporarily non-coaxial with each other.

Abstract: A known method for homogenizing glass includes the following steps: providing a cylindrical blank composed of the glass, having a cylindrical outer surface which extends between a first end face and a second end face, forming a shear zone in the blank by softening a longitudinal section of the blank and subjecting it to a thermal-mechanical intermixing treatment, and moving the shear zone along the longitudinal axis of the blank. To reduce the risk of cracks and fractures during homogenizing, it is proposed that a thermal radiation dissipator is used that at least partially surrounds the shear zone, the lateral dimension of which in the direction of the longitudinal axis of the blank is greater than the shear zone and smaller than the length of the blank, the thermal radiation dissipator being moved synchronously with the shear zone along the longitudinal axis of the blank.

Abstract: A process for the production of a fluorinated quartz glass including the steps of generating SiO2 particles in a synthesis burner; depositing the resulting SiO2 particles into a body; and vitrifying the resulting body, wherein a fluorinating agent having a boiling point greater than or equal to ?10° C. is supplied to the synthesis burner.

Abstract: The description relate to devices, such as augmented reality and/or virtual reality devices that employ optical waveguides. On example includes a first optical waveguide configured to receive light at an incidence angle and a second optical waveguide positioned in a non-parallel relation to the first optical waveguide. The second optical waveguide can be configured to receive the light through the first optical waveguide at a first location at the incidence angle, transmit the light within the second optical waveguide, and output the light from a second location back toward the first optical waveguide at the incidence angle.

Abstract: The description relate to devices, such as augmented reality and/or virtual reality devices that employ optical waveguides. On example includes a first optical waveguide configured to receive light at an incidence angle and a second optical waveguide positioned in a non-parallel relation to the first optical waveguide. The second optical waveguide can be configured to receive the light through the first optical waveguide at a first location at the incidence angle, transmit the light within the second optical waveguide, and output the light from a second location back toward the first optical waveguide at the incidence angle.

Abstract: A method for producing a component with portions of a rare earth metal-doped quartz glass, an intermediate product containing voids and consisting of a SiO2 raw material doped with rare earth metal is introduced into a sinter mold the interior of which is bordered by a carbonaceous mold wall, and is melted therein into the component by gas pressure sintering at a maximum temperature above 1500° C. A shield is arranged between the mold wall and the intermediate product. In order to indicate a modified gas pressure sintering method that ensures the production of rare earth metal-doped quartz glass with reproducible properties, a bulk material of amorphous SiO2 particles with a layer thickness of at least 2 mm is used as the shield, the softening temperature thereof being at least 20° C.

Abstract: In known methods for producing a glass component, a void-containing intermediate product containing doped or non-doped SiO2 is inserted into a sheath tube composed of glass, which has a longitudinal axis and an inner bore, and is thermally treated therein. In order to subject the intermediate product to a thermal and/or reactive treatment that is reproducible and uniform in its effect from this starting point, it is proposed in one embodiment that into the sheath tube's inner bore a first gas-permeable gas diffuser is inserted which is displaceable along the sheath tube's longitudinal axis and is pressed against the intermediate product during the thermal treatment.

Abstract: A method for homogenizing glass includes the method: providing a cylindrical blank composed of the glass having a cylindrical outer surface that extends along a longitudinal axis of the blank between a first end face and a second end face, forming a shear zone in the blank by softening a longitudinal section of the blank and subjecting it to a thermal-mechanical intermixing treatment, and displacing the shear zone along the longitudinal axis of the blank. To enable a radial mixing within the shear zone in addition to the tangential mixing with the lowest possible time and energy input, starting from this method, cylindrical sections of the blank are adjacent to the shear zone on both sides, the first cylindrical section having a first central axis and the second cylindrical section having a second central axis, the first central axis and the second central axis being temporarily non-coaxial with each other.

Abstract: A known method for homogenizing glass includes the following steps: providing a cylindrical blank composed of the glass, having a cylindrical outer surface which extends between a first end face and a second end face, forming a shear zone in the blank by softening a longitudinal section of the blank and subjecting it to a thermal-mechanical intermixing treatment, and moving the shear zone along the longitudinal axis of the blank. To reduce the risk of cracks and fractures during homogenizing, it is proposed that a thermal radiation dissipator is used that at least partially surrounds the shear zone, the lateral dimension of which in the direction of the longitudinal axis of the blank is greater than the shear zone and smaller than the length of the blank, the thermal radiation dissipator being moved synchronously with the shear zone along the longitudinal axis of the blank.

Abstract: Examples are disclosed that relate to the use of diffractive filtering in a waveguide display system. One example provides a display system including a light source, a first waveguide configured to conduct light of a first wavelength band from the light source, the first waveguide comprising a first input coupler, a second waveguide configured to conduct light of a second wavelength band from the light source, the second waveguide comprising a second input coupler, and a diffractive filter positioned optically between the first waveguide and the second waveguide, the diffractive filter being configured to diffract light of the first wavelength band and transmit light of the second wavelength band.

Abstract: A process for making cerium dioxide nanoparticles containing at least one transition metal (M) utilizes a suspension of cerium hydroxide nanoparticles prepared by mechanical shearing of an aqueous mixture containing an oxidant in an amount effective to enable oxidation of cerous ion to ceric ion, thereby forming a product stream that contains transition metal-containing cerium dioxide nanoparticles, Ce1-xMxO2, wherein “x” has a value from about 0.3 to about 0.8. The nanoparticles thus obtained have a cubic fluorite structure, a mean hydrodynamic diameter in the range of about 1 nm to about 10 nm, and a geometric diameter of less than about 4 nm. The transition metal-containing crystalline cerium dioxide nanoparticles can be used to prepare a dispersion of the particles in a nonpolar medium.

Abstract: A method for producing rare earth metal-doped quartz glass includes the steps of (a) providing a blank of the rare earth metal-doped quartz glass, and (b) homogenizing the blank by softening the blank zone by zone in a heating zone and by twisting the softened zone along a rotation axis. Some rare earth metals, however, show a discoloration of the quartz glass, which hints at an unforeseeable and undesired change in the chemical composition or possibly at an inhomogeneous distribution of the dopants. To avoid this drawback and to provide a modified method which ensures the production of rare earth metal-doped quartz glass with reproducible properties, during homogenization according to method step (b), the blank is softened under the action of an oxidizingly acting or a neutral plasma.

Abstract: A quartz glass tube as a semi-finished product for an optical component that has an inner bore extending along a tube center axis for the acceptance of a core rod and a tube wall limited by an inner casing surface and an outer casing surface is already known; within said tube wall an inner region made of a first quartz glass and an outer region made of a second quartz glass with a different index of refraction surrounding the inner region contact one another at a contact surface which runs around the center axis. In order to provide a quartz glass on this basis that facilitates the production of optical components for special applications such as laser-activated optical components in wand or fiber form, the invention states that the contact surface has a non-round course in the radial cross-section and the inner casing surface has a circular course.

Abstract: Examples are disclosed that relate to the use of diffractive filtering in a waveguide display system. One example provides a display system including a light source, a first waveguide configured to conduct light of a first wavelength band from the light source, the first waveguide comprising a first input coupler, a second waveguide configured to conduct light of a second wavelength band from the light source, the second waveguide comprising a second input coupler, and a diffractive filter positioned optically between the first waveguide and the second waveguide, the diffractive filter being configured to diffract light of the first wavelength band and transmit light of the second wavelength band.

Abstract: A method for producing a component with portions of a rare earth metal-doped quartz glass, an intermediate product containing voids and consisting of a SiO2 raw material doped with rare earth metal is introduced into a sinter mold the interior of which is bordered by a carbonaceous mold wall, and is melted therein into the component by gas pressure sintering at a maximum temperature above 1500° C. A shield is arranged between the mold wall and the intermediate product. In order to indicate a modified gas pressure sintering method that ensures the production of rare earth metal-doped quartz glass with reproducible properties, a bulk material of amorphous SiO2 particles with a layer thickness of at least 2 mm is used as the shield, the softening temperature thereof being at least 20° C.

Abstract: A method of making cerium dioxide nanoparticles includes: a) providing an aqueous reaction mixture having a source of cerous ion, a source of hydroxide ion, a nanoparticle stabilizer, and an oxidant at an initial temperature no higher than about 20° C.; b) mechanically shearing the mixture and causing it to pass through a perforated screen, thereby forming a suspension of cerium hydroxide nanoparticles; and c) raising the initial temperature to achieve oxidation of cerous ion to eerie ion and thereby form cerium dioxide nanoparticles having a mean diameter in the range of about 1 nm to about 15 nm. The cerium dioxide nanoparticles may be formed in a continuous process.

Abstract: The invention relates to a process for producing SiO2 granules by freezing and re-thawing an SiO2 suspension, wherein a separation of liquid and sediment composed of agglomerated SiO2 particles occurs in the course of thawing, the liquid removed is decanted and the residual moisture in the sediment is removed by a drying step with formation of the SiO2 granules. According to the invention, an auxiliary comprising alkali metal-free bases in the form of nitrogen hydrides is added to the suspension to set the pH greater than 7.