Abstract: A method of making a fused silica article that is loaded with hydrogen. A fused silica glass near net shape part is provided and is loaded with a molecular hydrogen in a range from about 0.1×1017 molecules/cm3 up to about 1×1019 molecules/cm3. The thinner shape of the near net shape part enables the shape to be loaded more quickly than previous methods. A fused silica article loaded with hydrogen using the method is also described.

Abstract: A method of making a fused silica article that is loaded with hydrogen. A fused silica glass near net shape part is provided and is loaded with a molecular hydrogen in a range from about 0.1×1017 molecules/cm3 up to about 1×1019 molecules/cm3. The thinner shape of the near net shape part enables the shape to be loaded more quickly than previous methods. A fused silica article loaded with hydrogen using the method is also described.

Abstract: A method of controlling blister formation in a glass melt flowing through a system comprising one ore more refractory metal vessels by developing a blister index and determining the critical blister index value. The critical value of the blister index may be used to control the principal variables responsible for blister formation, including the water content of the melt, the concentration of reduced multivalent oxide compounds in the melt, and the hydrogen partial pressure of an atmosphere in contact with the outside surface of the refractory metal vessel. Also disclosed is a minimum partial pressure of hydrogen necessary to produce an essentially blister-free glass article in a glass essentially free of arsenic and antimony.

Abstract: Feed materials are melted in a furnace to form a glass melt at a first temperature T1, the glass melt containing at least one fining agent. The glass melt is cooled to a second temperature T2 less than T1, and an oxygen-containing gas is bubbled through the cooled melt. The glass melt is then re-heated to a third temperature T3 equal to or greater than the first temperature T1.

Abstract: Disclosed in the application are a synthetic silica glass having low fluence-dependent transmission, particularly at about 193 nm, and a process for making the same. The glass may desirably exhibit a low level of fluorescence at 290 and 390 nm when activated at about 248 nm. The glass may desirably exhibit low level of LIWFD, [SiH*] and/or [ODC].

Abstract: Disclosed are high purity synthetic silica material having an internal transmission at 193 nm of at least 99.65%/cm and method of preparing such material. The material is also featured by a high compositional homogeneity in a plane transverse to the intended optical axis. The soot-to-glass process for making the material includes a step of consolidating the soot preform in the presence of H2O and/or O2.

Abstract: A method of making an optical fiber precursor includes generating vapors from an alkali metal source comprising compound containing oxygen and one or more alkali metals and applying the vapors to a surface of a glass article comprising silica at a temperature that promotes diffusion of the alkali metal into the surface of the glass article. An optical fiber has a core comprising silica and an alkali metal oxide of the form X2O, where X is selected from the group consisting of K, Na, Li, Cs, and Rb, wherein a concentration of the alkali metal oxide along a length of the core is uniform.

Abstract: A method of forming an alkali metal oxide-doped optical fiber by diffusing an alkali metal into a surface of a glass article is disclosed. The silica glass article may be in the form of a tube or a rod, or a collection of tubes or rods. The silica glass article containing the alkali metal, and impurities that may have been unintentionally diffused into the glass article, is etched to a depth sufficient to remove the impurities. The silica glass article may be further processed to form a complete optical fiber preform. The preform, when drawn into an optical fiber, exhibits a low attenuation.

Abstract: A method of forming an alkali metal oxide-doped optical fiber by diffusing an alkali metal into a surface of a glass article is disclosed. The silica glass article may be in the form of a tube or a rod, or a collection of tubes or rods. The silica glass article containing the alkali metal, and impurities that may have been unintentionally diffused into the glass article, is etched to a depth sufficient to remove the impurities. The silica glass article may be further processed to form a complete optical fiber preform. The preform, when drawn into an optical fiber, exhibits a low attenuation.

Abstract: Disclosed is a synthetic silica glass optical material having high resistance to optical damage by ultraviolet radiation in the ultraviolet wavelength range, particularly in the wavelength less than about 250 nm and particularly, exhibiting a low laser induced wavefront distortion; specifically a laser induced wavefront distortion, measured at 633 nm, of between about ?1.0 and 1.0 nm/cm when subjected to 10 billion pulses of a laser operating at approximately 193 nm and at a fluence of approximately 70 ?J/cm2. The synthetic silica glass optical material of the present invention comprises OH concentration levels of less than about 600 ppm, preferably less than 200 ppm, and H2 concentration levels less than about 5.0×1017 molecules/cm3,and preferably less than about 2.0×1017 molecules/cm3.

Abstract: The invention includes methods and apparatus for depositing soot onto a glass surface to minimize water in the deposited soot and the diffusion of the water into the glass surface. The invention includes depositing a first layer of soot a on the glass surface at a first forward traverse rate and depositing a second layer of soot at a second forward traverse rate.

Abstract: The invention is directed to improving the lifetime of optical assemblies by placing such assemblies in a housing and placing a “getter” material within the housing to remove substances that affect the surface of the optical elements used in such assemblies. The “getter” materials are those materials that can remove H2O and O2 from the operating environment of the optical element. The invention is useful in protecting the optical elements of below 250 nm laser lithography systems from damage due to pitting.