Abstract:
The present disclosure provides optical fiber preforms formed from core canes having large core-clad ratio, intermediate core-cladding assemblies, and methods for making the preforms and core cladding assemblies. The preforms are made with capped core canes. The capping material has a coefficient of thermal expansion less than the coefficient of thermal expansion of the core cane and more closely matched to or lower than the coefficient of thermal expansion of the surrounding cladding monolith in a cane-in-soot process. Presence of the cap reduces stresses that arise from differential thermal expansion of the core cane and cladding materials and leads to preforms having low defect concentration and low probability of failure during subsequent thermal processing steps.
Abstract:
A blank made of titanium-doped silica glass for a mirror substrate for use in EUV lithography is provided. The blank includes a surface portion to be provided with a reflective film and having an optically used area (CA) over which a coefficient of thermal expansion (CTE) has a two-dimensional inhomogeneity (dCTE) distribution profile averaged over a thickness of the blank. A maximum inhomogeneity (dCTEmax) of less than 5 ppb/K is defined as a difference between a CTE maximum value and a CTE minimum value. The dCTEmax is at least 0.5 ppb/K. The CA forms a non-circular area having a centroid. The dCTE distribution profile is not rotation-symmetrical and is defined over the CA, such that straight profile sections normalized to a unit length and extending through the centroid of the area yield a dCTE family of curves forming a curve band with a bandwidth of less than 0.5×dCTEmax.
Abstract:
A wavelength conversion structure comprises a sintered body comprising a mixture of a wavelength conversion material and a glass composition, wherein the wavelength conversion material comprises a phosphor and the glass composition comprises ZnO—BaO—SiO2—B2O3.
Abstract:
A wavelength conversion structure comprises a sintered body comprising a mixture of a wavelength conversion material and a glass composition, wherein the wavelength conversion material comprises a phosphor and the glass composition comprises ZnO-BaO-SiO2B2O3.
Abstract translation:波长转换结构包括包含波长转换材料和玻璃组合物的混合物的烧结体,其中波长转换材料包括磷光体,玻璃组合物包含ZnO-BaO-SiO 2 B 2 O 3。
Abstract:
High aspect ratio core optical fiber designs, which could be semi-guiding, including a core region having a first refractive index and a high aspect ratio elongated cross-section along a slow axis direction, are described. An internal cladding having a second refractive index sandwiches the core and acts as a fast-axis signal cladding. The core has an edge region at both of its short edges that is in contract with edge-cladding regions having a barbell shape. The refractive index of the core regions, the refractive index of the internal claddings, and the refractive index of the edge-cladding regions, are selected so as to maximize the optical power of a lowest-order mode propagating in the fiber core, and to minimize the optical power of the next-order modes in the fiber core. A process to fabricate such a high aspect ratio core fiber is also provided.
Abstract:
The invention concerns a method for making an optical fiber (18) including the following steps: producing a preform (10) containing nanoparticles provided with an active element including at least one recess (14) proximate at least part of the nanoparticles; fiber drawing of the preform (10) by introducing a non-oxidizing gas in the recess (14), thereby limiting the risks of oxidizing the nanoparticles of the preform (10). The preform (10) designed to the manufacture of an optical fiber (18) by the inventive method comprises nanoparticles provided with an active element in a doped zone (12) and at least one recess (14) proximate the doped zone (12).
Abstract:
A method for forming a silica glass blank includes generating soot using an array of soot producing burners, directing the soot along a first direction onto a bait, collecting the soot on the bait, imparting relative oscillatory motion having a repeat period between the array of soot producing burners and the bait along a second direction orthogonal to the first direction while collecting the soot, and offsetting the relative oscillatory motion by a selected distance along the second direction after each repeat period.
Abstract:
The invention is directed to the production of optical fibers from optical fiber preforms using flow physics. The present methods provide for the “drawing” of an optical fiber preform using focusing of the preform by a surrounding fluid, e.g. a heated gas.
Abstract:
A method for making silica includes delivering a silica precursor comprising a perfluorinated group to a conversion site and passing the silica precursor through a conversion flame to produce silica soot.
Abstract:
A method of forming an article, such as a low loss optical waveguide, by applying to a starting member a layer of glass soot to form a porous body. The porous body is then placed in a controlled environment in which a predetermined desired concentration of gases is maintained. The porous body is heated below the sintering temperature of the glass to permit entrapped gas to escape therefrom and the temperature is maintained until an equilibrium is reached between the partial pressure of the entrapped gas in the porous body and the partial pressure of the same gas in said environment. Thereafter, the porous body is further heated to at least the sintering temperature of the glass to sinter the soot particles and to form a consolidated dense member which may thereafter be formed into a desired shape while within said environment.