Abstract:
This invention pertains to a process of bonding a magnesium aluminate spinel article or articles and a germanate glass article or articles including the step of heating them together above the softening temperature of the glass.
Abstract:
The present invention is generally directed to a method of making a hollow-core photonic band gap preform from a specialty glass by pressing a specialty glass through a die to form a tube wherein the outer transverse shape of the tube is a hexagon, triangle, quadrilateral, or other polygon; stretching the tube to form a micro-tube with approximately the same outer transverse shape as the tube; stacking a plurality of micro-tubes into a bundle minimizing voids between adjacent micro-tubes and forming a central longitudinal void wherein the plurality of micro-tubes within the bundle comprise an inner structured region of the preform and the central void of the bundle comprises a hollow core in the preform; and inserting the bundle into a jacket tube. Also disclosed are the hollow-core photonic band gap preform and fiber formed by this method.
Abstract:
A transparent polycrystalline ceramic having scattering and absorption loss less than 0.2/cm over a region comprising more than 95% of the originally densified shape and a process for fabricating the same by hot pressing. The ceramic can be any suitable ceramic such as yttria (Y2O3) or scandia (Sc2O3) and can have a doping level of from 0 to 20% and a grain size of greater than 30 μm, although the grains can also be smaller than 30 μm. Ceramic nanoparticles can be coated with a sintering aid to minimize direct contact of adjacent ceramic powder particles and then baked at high temperatures to remove impurities from the coated particles. The thus-coated particles can then be densified by hot pressing into the final ceramic product. The invention further provides a transparent polycrystalline ceramic solid-state laser material and a laser using the hot pressed polycrystalline ceramic.
Abstract:
The present invention is generally directed to a bulk barium copper sulfur fluoride (BCSF) material made by combining Cu2S, BaS and BaF2, heating the ampoule between 400 and 550 ° C. for at least two hours, and then heating the ampoule at a temperature between 550 and 950 ° C. for at least two hours. The BCSF material may be doped with potassium, rubidium, or sodium. The present invention also provides for a BCSF transparent conductive thin film made by forming a sputter target by either hot pressing bulk BCSF or hot pressing Cu2S, BaS and BaF2 powders and sputtering a BCSF thin film from the target onto a substrate. The present invention is further directed to a p-type transparent conductive material comprising a thin film of BCSF on a substrate where the film has a conductivity of at least 1 S/cm. The substrate may be a plastic substrate, such as a polyethersulfone, polyethylene terephthalate, polyimide, or some other suitable plastic or polymeric substrate.
Abstract:
A waveguide amplifier, disposed on a substrate, composed of sputtered film of chalcogenide glass doped with Erbium is disclosed. The amplifier includes a substrate, a thick film of chalcogenide glass disposed on the substrate, a pumping device, and an optical combining device, wherein the waveguide is operable to amplify the optically combined signal. This type of amplifier has been shown to be compact and cost-effective, in addition to being transparent in the mid-IR range as a result of the low phonon energy of chalcogenide glass.
Abstract:
A functionally doped polycrystalline ceramic laser medium and method of making thereof are provided. The medium includes a solid state polycrystalline Ytterbium doped Yttria or Scandia (Yb:Y2O3 or Yb:Sc2O3) laser medium with a discrete or continuous gradient doping profile and methods for manufacturing the same. The doping profile can be two- or three-dimensional and can vary depending upon the laser geometry, the pumping scheme, and the benefits to be desired from the laser medium's structure. The grading direction can be linear, axial, radial, or any combination thereof. The material can be made from a combination of doped and undoped solid shapes, loose powders, and green shapes, and can be diffusion bonded or densified to a desired final shape using techniques such as pressureless sintering, hot pressing, hot forging, spark plasma sintering, and hot isostatic pressing (HIPing), or their combinations.
Abstract:
A thermally stable chalcogenide glass, a process for making the same, and an optical fiber drawn therefrom are provided. A chalcogenide glass having the composition Ge(5−y)As(32−x)Se(59+x)Te(4+y) (0≦y≦1 and 0≦x≦2) is substantially free from crystallization when it is heated past the glass transition temperature Tg or drawn into optical fibers. A process for making the thermally stable chalcogenide glass includes purifying the components to remove oxides and scattering centers, batching the components in a preprocessed distillation ampoule, gettering oxygen impurities from the mixture, and heating the components to form a glass melt. An optical fiber formed from the chalcogenide glass is substantially free from crystallization and exhibits low signal loss in the near-infrared region, particularly at wavelengths of about 1.55 μm.
Abstract:
A doped glass composition is provided. A base glass is doped with rare earth ions Terbium Tb3+ and Europium Eu3+ to produce a glass that reduces the transmission of short-wave infrared radiation therethrough without reducing the transmission of visible light. A base glass composition is doped with Tb3+ and Eu3+ ions to an appreciable concentration, in some embodiments in excess of 5 mol % and in other embodiments to a concentration in excess of 1 mol %. A suitable glass for doping according to the present invention includes any glass that can accept rare earth ions at appreciable densities such as the densities described above, and can include oxide-based, fluoride-based, and chalcogenide-based glasses. The doped glass attenuates transmission of short-wave infrared radiation having wavelengths of about 1.8 μm to about 2.5 μm and does not reduce transmission of visible light having wavelengths from about 0.4 μm to about 0.8 μm.
Abstract:
A high purity nano-sized Yb3+ doped Y2O3 (Yb:Y2O3) ceramic powder with a narrow size distribution and without hard agglomerates is provided. Also provided is a process for manufacturing the same wherein water in the reaction bath is replaced by a non-water washing agent having little or no hydrogen bonding capability to inhibit the formation of hard agglomerates in the ceramic powder.
Abstract:
A transparent polycrystalline ceramic having scattering and absorption loss less than 0.2/cm over a region comprising more than 95% of the originally densified shape and further provides a process for fabricating the same by hot pressing. The ceramic can be any suitable ceramic such as yttria (Y2O3) or scandia (Sc2O3) and can have a doping level of from 0 to 20% and a grain size of greater than 30 μm, although the grains can also be smaller than 30 μm. In a process for making a transparent polycrystalline ceramic in accordance with the present invention, ceramic nanoparticles can be coated with a sintering aid to minimize direct contact of adjacent ceramic powder particles and then baked at high temperatures to remove impurities from the coated particles. The thus-coated particles can then be densified by hot pressing into the final ceramic product. The invention further provides a transparent polycrystalline ceramic solid-state laser material and a laser using the hot pressed polycrystalline ceramic.