Abstract:
The present invention relates to a glass article for use as an optical waveguide fiber and more particularly to an optical waveguide fiber, the core of which is doped with a chalcogenide element to significantly increase the refractive index of the core. The subject of this invention is novel doped silica core compositions wherein a portion of the oxygen in the silica is replaced with either sulfur, selenium or tellurium using plasma enhanced chemical vapor deposition (PECVD). These compositions are designed to have higher refractive indices than silica, low coefficients of expansion, high optical transparency, and appropriate viscosity and softening points to make them ideal candidates for use as optical waveguide fibers.
Abstract:
Fused silica articles containing at least 50 ppb aluminum are disclosed. The fused silica articles containing these levels of aluminum exhibit improved internal transmission and decreased absorption change when irradiated with a laser when compared with fused silica articles containing lower levels of aluminum.
Abstract:
The present invention relates to a glass article for use as an optical waveguide fiber and more particularly to an optical waveguide fiber, the core of which is doped with a chalcogenide element to significantly increase the refractive index of the core. The subject of this invention is novel doped silica core compositions wherein a portion of the oxygen in the silica is replaced with either sulfur, selenium or tellurium using plasma enhanced chemical vapor deposition (PECVD). These compositions are designed to have higher refractive indices than silica, low coefficients of expansion, high optical transparency, and appropriate viscosity and softening points to make them ideal candidates for use as optical waveguide fibers.
Abstract:
Fused silica articles exhibiting improved internal transmission and decreased absorption change when irradiated with a laser when compared with fused silica articles containing lower levels of aluminum. The articles also exhibit induced transmission when irradiated with a laser.
Abstract:
High purity silicon oxyfluoride glass suitable for use as a photomask substrates for photolithography applications in the VUV wavelength region below 190 nm is disclosed with the silicon oxyfluoride glass having a preferred fluorine content
Abstract translation:公开了具有优选氟含量<0.5重量%的氟氧化硅玻璃,适合用作光刻应用中的低于190nm的VUV波长区域的光掩模基板的高纯度氟氧化硅玻璃。 本发明的氟氧化硅玻璃在157nm波长下是透射的,使其特别适用于157nm波长区域的光掩模衬底。 本发明的光掩模基材是“真空”的氟氧化硅玻璃,其在真空紫外(VUV)波长区域中表现出非常高的透射率,同时保持通常与高纯度熔融石英相关的优异的热和物理性能。 除了含氟并且具有很少或不含OH含量之外,本发明的适合用作157nm的光掩模衬底的氟氧化硅玻璃的特征还在于具有小于1×10 17分子/ cm 3的分子氢和低氯水平。
Abstract:
In a method of making a high-quality silica glass, a rare earth element that is a substance making a great contribution to the index of refraction is introduced therein together with aluminum for stabilizing the glass. An alkoxide of aluminum or its derivative is used as the starting material for preparing a boehmite sol. A salt of at least one element selected from rare earth elements or a solution in which the salt is dissolved and the boehmite sol are mixed with a silica sol, whereupon the sols are vitrified.
Abstract:
A synthetic quartz powder obtained by calcining a powder of silica gel, characterized in that white devitrification spots having sizes of larger than 20 &mgr;m in diameter formed in an ingot obtained by vacuum melting the synthetic quartz powder at a temperature of from 1780 to 1800° C. to form an ingot, followed by maintaining the ingot at a temperature of 1630° C. for 5 hours, are at most 10 spots/50 g.
Abstract:
A novel copper activated thermoluminescence dosimeter comprising a glass composition having: about 94-97 weight percent SiO.sub.2 ; about 0.4 to 2 weight percent Al.sub.2 O.sub.3 ; about 0.02 to 1 weight percent M.sub.2 O, where M comprises Na.sup.+ or K.sup.+ ; about 2 to 6 weight percent B.sub.2 O.sub.3 ; and Cu(I), where Cu(I) is present at a level between about 10.sup.18 to 10.sup.19 ions/cm.sup.3 ; method of making the same.
Abstract:
A yellow color by transmitted light is produced in a high silica glass by impregnating a porous, high silica glass with a solution of chromium and zinc salts and consolidating the glass under oxidizing conditions to dope the glass with chromium and zinc oxides, the chromium being predominantly in the hexavalent state. Optionally, an aluminum salt is included in the impregnating solution. The glass has particular utility as a filter for lighting purposes.
Abstract:
The present invention comprises a process for separating rare earth ions or actinide ions or mixtures thereof in solution by passing the solution through an ion exchange material to separate the rare earths or actinides or mixtures thereof. The ion exchange material has a surface area of about 5-1500 m.sup.2 /g. The ion exchange material is impregnated with a liquid containing alkali metal cations, Group Ib metal cations, ammonium cations, organic amines or mixtures thereof, at a pH range above about 9. A plurality of fractions of the solution is collected as the solution passes through the ion exchange material, preferably in a column. This process is particularly preferred for separating rare earth ions and especially lanthanum and neodymium. It is particularly preferred to purify lanthanum to contain less than 0.1 ppm, preferably less than 0.01 ppm, of neodymium. In another embodiment, the present invention comprises a method of producing a porous silicate glass containing at least one transition metal oxide additive selected from a group consisting of the bottom two rows of Group VIII of the Periodic Table. This method comprises preparing a base glass from a melt which contains 40-80 mol percent of silica and up to 10 mol percent of one or more transition metal oxide additives selected from said group or of precursors of said oxide additives, separating said base glass by heat treatment into at least a soluble phase and an insoluble phase, leaching out the soluble phase. In yet another embodiment, the present invention comprises an ion exchange material consisting of a porous glass or silica gel including at least about 0.2 mol percent of a transition metal oxide or hydrous metal oxide and containing at least 0.3 mol percent of alkali metal cation, Group Ib metal cation, ammonium, organic amines, or mixtures thereof.