Abstract: A standoff chemical detection system that includes a source and detector are provided. The source includes: a controller, memory communicatively connected to the controller, optical sources each constructed to operate over different wavelength ranges, and a power supply. The controller controls the plurality of optical sources to emit respective infrared beams towards a target detection area in a sequential order. The detector includes: an image sensor and a controller that is communicatively connected to the image sensor. Memory and the notification device are also communicatively connected to the controller. The image sensor receives attenuated infrared beams emitted by the optical sources sequentially and at least partially attenuated by chemicals in the target detection area. The controller is constructed to calculate stimulus value signals from the recorded image data and determine whether a hazard chemical is located within the target detection area based on the calculated stimulus value signals.

Abstract: Tunable devices and methods for fine tuning the optical responses of thin film devices post fabrication are described. This approach modifies the refractive indices of the chalcogenide glass thin films incorporated into the devices, and using this change in the refractive indices to fine tune the optical responses of the devices. Thermal annealing may be used to modify the refractive index. Thermal annealing provides good uniformity in large-area devices and may be applied to multi-layer structures.

Abstract: A standoff chemical detection system that includes a source and detector are provided. The source includes: a controller, memory communicatively connected to the controller, optical sources each constructed to operate over different wavelength ranges, and a power supply. The controller controls the plurality of optical sources to emit respective infrared beams towards a target detection area in a sequential order. The detector includes: an image sensor and a controller that is communicatively connected to the image sensor. Memory and the notification device are also communicatively connected to the controller. The image sensor receives attenuated infrared beams emitted by the optical sources sequentially and at least partially attenuated by chemicals in the target detection area. The controller is constructed to calculate stimulus value signals from the recorded image data and determine whether a hazard chemical is located within the target detection area based on the calculated stimulus value signals.

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 photonic band gap fiber and method of making thereof is provided. The fiber is made of a non-silica-based glass and has a longitudinal central opening, a microstructured region having a plurality of longitudinal surrounding openings, and a jacket. The air fill fraction of the microstructured region is at least about 40%. The fiber may be made by drawing a preform into a fiber, while applying gas pressure to the microstructured region. The air fill fraction of the microstructured region is changed during the drawing.

Abstract: This invention pertains to fiber termination combination which includes an optical fiber having a fiber core for transmitting a highly energetic optical signal that can damage the fiber and a structured region around the core for directing the optical signal into the core, the structured region being characterized by multiple channels of smaller internal diameter than the core defined by thin walls disposed around said core; a ferrule, with an opening therein for locating said fiber, at the end of said fiber enveloping said fiber extremity which cooperates with said blocking structure to block the optical signal from impinging on said microstructured region of said fiber; and a blocking structure disposed over the end of said fiber with an opening mating with said fiber core, said blocking structure blocking the optical signal from impinging on said microstructured region of said fiber.

Abstract: A hollow core photonic bandgap chalcogenide glass fiber includes a hollow core for passing light therethrough, a Raman active gas disposed in said core, a microstructured region disposed around said core, and a solid region disposed around said microstructured region for providing structural integrity to said microstructured region. A coupler can introduce at least one light signal into the hollow core of the chalcogenide photonic bandgap fiber. The method includes the steps of introducing a light beam into a hollow core chalcogenide photonic bandgap glass fiber filled with a Raman active gas disposed in the core, conveying the beam through the core while it interacts with the gas to form a Stokes beam of a typically higher wavelength, and removing the Stokes beam from the core of the fiber.

Abstract: A photonic band gap fiber and method of making thereof is provided. The fiber is made of a non-silica-based glass and has a longitudinal central opening, a microstructured region having a plurality of longitudinal surrounding openings, and a jacket. The air fill fraction of the microstructured region is at least about 40%. The fiber may be made by drawing a preform into a fiber, while applying gas pressure to the microstructured region. The air fill fraction of the microstructured region is changed during the drawing.

Abstract: This invention pertains to a composite of Spinel and BGG glass substrates and to process for bonding Spinel to BGG glass. The composite includes a Spinel and a BGG glass bonded together and having transmission in the visible and mid-infrared wavelength region. The process includes the step of heating them together above the softening temperature of the BGG glass, the composite having excellent, i.e., typically in excess of about 80%, transmission in the 0.5-5 wavelength region.

Abstract: This invention pertains to a composite of AlON and a germanate glass, and to a process for bonding AlON to the glass. The composite includes AlON and glass bonded together and having transmission in the visible and mid-infrared wavelength region. The process includes the step of heating them together above the softening temperature of the glass, the composite having excellent, i.e., typically in excess of about 60%, transmission in the 0.4-5 wavelength region.

Abstract: A process includes the steps of disposing a solid core glass rod at a point removed from hot temperature that can cause crystallization in the core glass rod, disposing a solid clad glass rod at a point removed from the core glass rod; softening to the flowing condition the solid clad glass rod, transferring the softened clad glass to a lower point, the softened clad glass having a central void therethrough, heating the softened clad glass above its crystallization temperature, cooling the softened clad glass to a draw temperature, transferring the solid core glass rod into the central void in the softened glad glass, softening to the flowing condition the solid core glass rod with the heat from the softened and cooled clad glass, and drawing the core/clad, glass fiber by allowing the clad and core glasses to flow in the form of a fiber.

Abstract: This invention pertains to fiber termination combination which includes an optical fiber having a fiber core for transmitting a highly energetic optical signal that can damage the fiber and a structured region around the core for directing the optical signal into the core, the structured region being characterized by multiple channels of smaller internal diameter than the core defined by thin walls disposed around said core; a ferrule, with an opening therein for locating said fiber, at the end of said fiber enveloping said fiber extremity which cooperates with said blocking structure to block the optical signal from impinging on said microstructured region of said fiber; and a blocking structure disposed over the end of said fiber with an opening mating with said fiber core, said blocking structure blocking the optical signal from impinging on said microstructured region of said fiber.

Abstract: This invention pertains to a glass fiber, a Raman device and a method. The fiber is a hollow core photonic bandgap chalcogenide glass fiber that includes a hollow core for passing light therethrough, a Raman active gas disposed in said core, a microstructured region disposed around said core, and a solid region disposed around said microstructured region for providing structural integrity to said microstructured region. The device includes a coupler for introducing at least one light signal into a hollow core of a chalcogenide photonic bandgap fiber; a hollow core chalcogenide photonic bandgap glass fiber; a microstructured fiber region disposed around said core; a solid fiber region disposed around said microstructured region for providing structural integrity to said microstructured region; and a Raman active gas disposed in the hollow core.

Abstract: This invention pertains to a hollow core photonic band gap chalcogenide optical glass fiber and to a fabrication method for making the fiber. The fiber, which is 80-1000 microns in outside diameter, is characterized by a solid glass circumferential region and a structured region disposed centrally within the solid region, the structured region includes a hollow core of 1 micron to several hundreds of microns in diameter surrounded by a plurality of parallel hollow capillaries extending parallel to the core, the core being centrally and longitudinally located within the fiber. Ratio of open space to glass in the structured region is 30-99%. The fabrication method includes the steps of providing a mold, placing chalcogenide micro-tubes around the mold, stacking chalcogenide micro-canes around the stacked micro-tubes, fusing the micro-tubes and the micro-canes to form a preform, removing the mold and drawing the preform to obtain the fiber.

Abstract: A ceramic having at least about 90% by weight magnesium aluminate and having a bulk scattering and absorption loss of less than about 1/cm at any wavelength in a range of about 0.23 to about 5.3 microns or 0.2/cm at any wavelength in a range of about 0.27 to about 4.5 microns. A method of making a ceramic by providing a plurality of particles having a magnesium aluminate core and a fluoride salt coating; heating the particles in an oxidizing atmosphere to a temperature in the range of about 400° C. to about 750° C.; and sintering the particles to form a solid ceramic.

Abstract: A particle having a magnesium aluminate core and a fluoride salt coating on the core. The particle has been heated in an oxidizing atmosphere to a temperature in the range of about 400° C. to about 750° C. A method of making a particle by mixing a magnesium aluminate core with a solution of a fluoride salt in a solvent to form a slurry and spraying the slurry into a drying column. The slurry enters the column as an aerosol under thermal conditions that avoid boiling the solvent. The thermal conditions in the column evaporate the solvent as the aerosol moves through the column to form a coating of the fluoride salt on the core while substantially avoiding spalling.

Abstract: This invention pertains to a device for broadening optical wavelength in the 2-14 ?m region comprising a light source and a highly nonlinear chalcogenide fiber associated therewith whereby a light signal is passed from the light source into the fiber wherein and through interactions between the light signal and the material, bandwidth of the light signal is broadened in the 2-14 ?m region.

Abstract: The coating method includes the steps of dissolving coating precursor(s) in a solvent to form a precursor solution: adding with mixing a miscible diluent to the precursor solution to form a coating solution; admixing solid particles to the coating solution to form a coating slurry, with the particles surrounded with the coating solution; spraying the coating slurry to form droplets containing at least one particle; passing the droplets through a drying zone where the droplets are dried and form dry particles coated with a coating material formed from the coating precursor(s); heat-treating the coating material on the particles emanating from the drying zone to remove volatile matter on the coating material, to improve integrity of the coating material and/or to effect another objective; and collecting dry coated particles.

Abstract: This invention pertains to a hollow core photonic band gap chalcogenide optical glass fiber and to a fabrication method for making the fiber. The fiber, which is 80-1000 microns in outside diameter, is characterized by a solid glass circumferential region and a structured region disposed centrally within the solid region, the structured region includes a hollow core of 1 micron to several hundreds of microns in diameter surrounded by a plurality of parallel hollow capillaries extending parallel to the core, the core being centrally and longitudinally located within the fiber. Ratio of open space to glass in the structured region is 30-99%. The fabrication method includes the steps of providing a mold, placing chalcogenide micro-tubes around the mold, stacking chalcogenide micro-canes around the stacked micro-tubes, fusing the micro-tubes and the micro-canes to form a preform, removing the mold and drawing the preform to obtain the fiber.

Abstract: This invention pertains to a chalcogenide glass of low optical loss that can be on the order of 30 dB/km or lower, and to a process for preparing the chalcogenide glass.