Abstract:
In one aspect, a method is provided for molding from glass complex optical components such as lenses, microlens, arrays of microlenses, and gratings or surface-relief diffusers having fine or hyperfine microstructures suitable for optical or electro-optical applications. In another aspect, mold masters or patterns, which define the profile of the optical components, made on metal alloys, particularly titanium or nickel alloys, or refractory compositions, with or without a non-reactive coating are provided. Given that molding optical components from oxide glasses has numerous drawbacks, it has been discovered in accordance with the invention that non-oxide glasses substantially eliminates these drawbacks. The non-oxide glasses, such as chalcogenide, chalcohalide, and halide glasses, may be used in the mold either in bulk, planar, or power forms. In the mold, the glass is heated to about 10-110° C., preferably about 50° C., above its transition temperature (Tg), at which temperature the glass has a viscosity that permits it to flow and conform exactly to the pattern of the mold.
Abstract:
High index-contrast fiber waveguides, materials for forming high index-contrast fiber waveguides, and applications of high index-contrast fiber waveguides are disclosed.
Abstract:
High index-contrast fiber waveguides, materials for forming high index-contrast fiber waveguides, and applications of high index-contrast fiber waveguides are disclosed.
Abstract:
In general, in one aspect, the invention features a method that includes exposing a surface to a first gas composition under conditions sufficient to deposit a layer of a first chalcogenide glass on the surface, and exposing the layer of the first chalcogenide glass to a second gas composition under conditions sufficient to deposit a layer of a second glass on the layer of the first chalcogenide glass, wherein the second glass is different from the first chalcogenide glass.
Abstract:
A method of making chalcogenide glass which utilizes liquid encapsulation to prevent the evaporation loss of low boiling point or high vapor pressure glass components while the glass melt is being processed.
Abstract:
High index-contrast fiber waveguides, materials for forming high index-contrast fiber waveguides, and applications of high index-contrast fiber waveguides are disclosed.
Abstract:
A process for producing a preform for a chalcogenide glass fiber which comprises inserting a cladding tube having contained therein a chalcogenide glass rod for core into a quartz tube having at its bottom a nozzle having an aperture smaller than the outer diameter of the cladding tube, locally heating the bottom of the quartz tube and pulling the cladding tube having contained the glass rod for core and a process for producing a chalcogenide glass fiber by heating and drawing the preform thus obtained, by which processes the devitrification of glass and the generation of bubbles in the core glass or at the core glass-cladding glass interface can be prevented and the adhesion between the core glass and the cladding glass can be improved. In particular, when the glass material for core does not contain Ge, a chalcogenide glass fiber having such a core-cladding structure that the transmission loss of the glass fiber when infrared light pass through the fiber is small and the mechanical strength is high.
Abstract:
A core/clad glass optical fiber is made by melting a core glass rod and a adding glass rod in separate crucibles which are not intersecting with respect to each other and the respective core and cladding glass melts passed out of contact with each other to a glass melt contacting zone proximate a fiber drawing orifice in which the cladding glass surrounds the core glass and a core/clad glass fiber is drawn. This process enables the clad glass fiber to be drawn directly from core and cladding glass rods without the need for a preform or forming a melt from glass chards or chunks, thereby reducing the cost of producing the fiber and also producing a glass clad optical fiber of high purity and excellent concentricity. Chalcogenide glass fibers having a concentricity of 100% have been made.
Abstract:
An infrared transmitting chalcogenide glass lens having precision optical surfaces of different curvature radii is molded. A pair of molds having different curvature radiuses from each other, and a bushing which controls the thickness of the lens is provided. A block of chalcogenide glass is placed within the cavity. The upper mold, the lower mold and the block of glass are heated with the mold having a smaller curvature radius being at a higher temperature than the other mold. The glass is then pressed, cooled, and the resulting lens is removed from the mold assembly.
Abstract:
Halide fibers are protected by coatings up to 2.mu.m thick of chalcogenide glasses, e.g. glasses based on compounds of S, Se or Te with Ge or As. The coatings are deposited on the fiber preform by ion deposition sputtering. Preferably the preform is etched by directing a stream of inert ions at it. Most suitably the etching immediately precedes the coating.