Abstract: Disclosed are optical gain fibers which include an erbium-containing core and a cladding surrounding the core and which have ripple of less than about 25% over about a 40 nm wide window or ripple of less than about 15% over about a 32 nm wide window, or both. In one embodiment, the optical gain fibers are pumpable at 980 nm and at 1480 nm. In another embodiment, the optical gain fibers are fusion sliceable. In yet another embodiment, the core includes oxides erbium; the cladding includes silicon dioxide; and the optical gain fiber has a passive loss of less than about 0.5% of the peak absorption of the erbium absorption band in the vicinity of 1530 nm. The optical gain fibers of the present invention have a wider gain window, improved flatness across the gain window, and/or increased gain as compared to conventional optical gain fibers.

Abstract: The invention relates to optical fluoride crystals, and particularly to optical fluoride crystals such as calcium fluoride, which have high transmission levels to below 200 nm light, such as produced by excimer lasers. In particular the invention relates to making optical fluoride crystals with improved transmission surfaces. The invention relates to the elimination of mid-spatial frequency roughness 1-1000 &mgr;m spatial wavelengths and high-spatial frequency<1 &mgr;m spatial wavelengths from optical fluoride crystal surfaces. The removal of the mid-spatial frequency 1-1000 &mgr;m spatial wavelengths and high-spatial frequency<1 &mgr;m spatial wavelengths from the optical fluoride crystal surfaces provides improved transmission at below 200 nm optical lithography wavelengths such as 193 nm and 157 nm.

Abstract: The present invention is directed to chromophores having novel electron withdrawing groups and novel bivalent cyclic bridges and to optical waveguides and optical devices having polymeric thin films which contain the novel chromophores.

Abstract: An article of relatively pure silica, and a furnace and method of producing the article. The article is produced by collecting molten silica particles in a refractory furnace in which at least a portion of the refractory has been exposed to a halogen-containing gas to react with contaminating metal ions in the refractory.

Abstract: A method of modifying the spectral distribution of an optical signal includes the steps of splitting the signal among a plurality of optical paths, delaying the propagation of the signal through one or more of the optical paths by a time duration which results in the desired spectral distribution when the signals at the output ends of each optical path are recombined, and then recombining those outputs. An apparatus for changing the spectral profile of an optical signal includes an input waveguide and a plurality of tapped delay lines. Each of the tapped delay lines has a delay element configurable to impart a predetermined delay to the signal propagating down the delay line. Couplers split an optical signal, propagating on the input waveguide, among the tapped delay lines. The delays imparted to the signals on each line are chosen so as to effect the desired change to the spectral profile.

Abstract: The present invention features an optical component based on a wavelength-dispersive element in conjunction with reflective elements to provide wavelength-sensitive control multi-wavelength light signals such as wavelength division multiplexed (WDM) light signals. Both static reflective elements and movable (dynamic) reflective elements are described. Optical devices such as gain-flattening filters and dynamically configurable wavelength selective routers with built-in gain flattening filters are described.

Abstract: A method of manufacturing a planar or integrated optical circuit in which a core layer (20) is formed on a substrate (10) and patterned to define optical features (such as waveguides) using a mask having a first portion (30) defining the desired core patterns (20a) and a second portion (35) corresponding to one or more alignment marks (20b). After etching the core layer, only the first portion (30) of the mask is removed, the second portion (35) of the mask being left to provide alignment marks (20b) which are highly visible through the subsequently-deposited overclad layer (40). The alignment marks (20b) are very accurately positioned with respect to the core patterns (20a), thus enabling further optical devices to be overlaid on the existing structure with accurate alignment to the underlying core patterns. The mask material (35) left on the alignment marks (20b) may be partially oxidized before the overclad is deposited.

Abstract: A method of modifying the spectral distribution of an optical signal includes the steps of splitting the signal among a plurality of optical paths, delaying the propagation of the signal through one or more of the optical paths by a time duration which results in the desired spectral distribution when the signals at the output ends of each optical path are recombined, and then recombining those outputs. An apparatus for changing the spectral profile of an optical signal includes an input waveguide and a plurality of tapped delay lines. Each of the tapped delay lines has a delay element configurable to impart a predetermined delay to the signal propagating down the delay line. Couplers split an optical signal, propagating on the input waveguide, among the tapped delay lines. The delays imparted to the signals on each line are chosen so as to effect the desired change to the spectral profile.

Abstract: A method for forming a sol-gel on a metal surface to provide an interface for promoting adhesion between the metal surface and an organic resin involves application of at least one metal alkoxide compound having at least one labile sulfur atom, and at least one metal alkoxide compound having at least one reactive moiety which is capable of bonding with an organic resin. The metal alkoxide compound having at least one labile sulfur atom is capable of bonding to various metal surfaces, including surfaces of noble metals, such as gold, by a sulfur-metal linkage with the metal surface. The metal alkoxide compound having at least one labile sulfur atom reacts with the metal alkoxide compound having at least one reactive moiety which is capable of bonding with the organic resin to form a sol-gel which bonds to the surface of the metal, and which includes reactive moieties which are capable of bonding with an organic resin.

Abstract: The present invention is directed to electro-optico chromophore bridge compounds and donor-bridge compounds which can be used in the preparation of polymeric thin films for waveguide media.

Abstract: A planar optical device is formed on a substrate. The device comprises an array of waveguide cores which guide optical radiation. A cladding layer is formed contiguously with the array of waveguide cores to confine the optical radiation to the array of waveguide cores. At least one of the array of waveguide cores and cladding layer is an inorganic-organic hybrid material that comprises an extended matrix containing silicon and oxygen atoms with at least a fraction of the silicon atoms being directly bonded to substituted or unsubstituted hydrocarbon moieties. This material can be designed with an index of refraction between 1.4 and 1.55 and can be deposited rapidly to thicknesses of up to 40 microns. In accordance with another embodiment of the invention, a method for forming a planar optical device obviates the need for a lithographic process.

Abstract: A method of making an in situ shaped optical element on the terminal end of an optical fiber, and the resultant optical fiber component for manipulating light entering or exiting the terminal end of an optical fiber. The in situ shaped optical element is preferably an inorganic-organic hybrid sol-gel material which is adhered to the terminal end of the optical fiber and shaped in place to define an optical element or surface.

Abstract: A process for the recovery of a volatile organic compound (VOC) from a process stream by use of a bed of activated carbon is disclosed. In the first step, VOC laden gas passes through to the bed, in a first direction. In the second step, steam passes through the bed in a second direction. The first direction is opposite to the second direction. In the final step, cooling gas, ambient atmospheric air, passes through the bed in the second direction. This process yields greater VOC recovery efficiency and longer cycle life for the bed of activated carbon.

Abstract: The present invention is directed to dicyanomethylenedihydrofuran-based electron acceptors which can be used in the preparation of polymeric thin films for waveguide media, and methods of making the same.

Abstract: An integrated planar Bragg grating is fabricated by depositing layers of material onto a negative expansion substrate to form a waveguide, which is held in mechanical tension with the substrate. A Bragg grating is then formed in the waveguide. As the temperature of the waveguide increases, the mechanical tension between the waveguide and the substrate is relieved, such that the peak reflection wavelength of the Bragg grating remains nearly constant.

Abstract: A copolymer containing N-(halogenated phenyl) maleimide units or N-(halogenated phenyl) bismaleimide units and one or more second units selected from halogenated acrylates, halogenated styrenes, halogenated vinyl ether, halogenated olefins, halogenated vinyl isocyanates, halogenated N-vinyl amides, halogenated allyls, halogenated propenyl ethers, halogenated methacrylates, halogenated maleates, halogenated itaconates, and halogenated crotonates, is useful to form optical devices

Abstract: The disclosure disclosed a fabric made of cellulose acetate and/or cellulose triacetate, and optionally fibers of other selected substances, which are calendered at selected temperatures and pressures after having been water-wetted to a selected water content in order to bond the fibers of cellulose acetate and/or triacetate to one another and/or to fibers of the other selected substances. The selected calendering temperatures are from about 130° C. to about 210° C., preferably from about 160° C. to about 190° C.; the selected pressures are from about 500 to about 5000 psi, preferably from about 500 to about 2500 psi and most preferably from about 1000 to about 2500 psi; and selected water content is from about 20% to about 600% of fabric dry weight. The physical properties of the calendered fabric, for example the stiffness or hand resulting from different degrees of bonding can be changed by altering one or more of there parameters, either separately or in combination.

Abstract: The present invention discloses and claims a novel process for the formation of high denier as-spun and heat-treated multilobal filaments of a thermotropic liquid crystalline polymer. Preferred embodiments include process for the formation of as-spun and heat treated octalobal monofilaments of a few wholly aromatic polyesters and polyesteramides. The process involves (a) heating of a thermotropic liquid crystalline polymer to above its melting transition temperature; (b) passing said molten polymer through an extrusion chamber equipped with an extrusion capillary having a multilobal cross-section to form a multilobal filament; and (c) winding the filament at a suitable draw-down. The filaments so formed are of at least 50 denier per filament (dpf) and feature essentially uniform molecular orientation across their cross-section. In a final optional step, the filaments are heat treated in stages to form filaments exhibiting excellent tensile properties.

Abstract: The present invention discloses and claims a novel process for the heat treatment of high denier filaments of a thermotropic liquid crystalline polymer. Preferred embodiments include process for the formation of heat treated filaments of a few wholly aromatic polyesters and polyesteramides. The process involves: (a) heating of a thermotropic liquid crystalline polymer to above its melting transition temperature; (b) passing said molten polymer through an extrusion chamber equipped with an extrusion capillary of an aspect ratio of greater than about 1 and less than about 15 to form a filament; (c) winding the filament on to a bobbin at a low tension and draw-down ratio of at least about 4; and (d) heat treating the filament directly on the bobbin at suitable temperature and pressure conditions for a sufficient period of time. The filaments so formed are of at least 50 denier per filament (dpf) and feature essentially uniform molecular orientation across the cross-section.

Abstract: The present invention discloses and claims a novel process for the formation of high denier as-spun and heat-treated filaments of a thermotropic liquid crystalline polymer. Preferred embodiments include process for the formation of as-spun and heat treated monofilaments of a few wholly aromatic polyesters and polyesteramides. The process involves (a) heating of a thermotropic liquid crystalline polymer to above its melting transition temperature; (b) passing said molten polymer through an extrusion chamber equipped with an extrusion capillary of an aspect ratio of greater than about 1 and less than about 15 to form a filament; and (c) winding the filament at a draw-down ratio of at least about 4. The filaments so formed are of at least 50 denier per filament (dpf) and feature essentially uniform molecular orientation across the cross-section. In a final optional step, the filaments are heat treated in stages to form filaments exhibiting excellent tensile properties.