Abstract: In accordance with the invention a high power, broad bandwidth light source comprises at least one rare earth doped fiber coupled to a long period grating. When the rare earth doped fiber is pumped to operate as an amplified spontaneous emission source, the grating flattens and broadens the output spectrum. Using an Nd doped fiber, applicants have achieved an output power of 25 mW at a center wavelength of 1.08 .mu.m, a spectral width of 40 nm and a coherence length of 10 .mu.m. The source has a flat output spectrum with a maximum slope of 0.1 dB/nm across the full spectral width, and it can be conveniently dropped into any fiber system requiring high power and a broad spectrum. Using an Er-doped fiber, applicants have achieved an output power of 7.3 mW at a center wavelength of 1.55 .mu.m and a spectral width of 38 nm. The source has a flat output spectrum with a maximum ripple of 1.7 dB across the full width. This source is compatible with the needs for a spectrum sliced source.

Abstract: Applicants have discovered that films of conductively doped GaInO.sub.3 grown on substrates by pulsed laser deposition have conductivity comparable to conventional wide band-gap transparent conductors while exhibiting superior light transmission, particularly in the green and blue wavelength regions of the visible spectrum. Substrate temperatures ranged from room temperature to 350.degree. C. in an ambient containing oxygen at partial pressure in the range 0.1 mTorr to 100 mTorr. The preferred laser source was an excimer laser operating in the deep ultraviolet.

Abstract: The present inventors have discovered how to make continuous films of single-phase crystalline .beta.-C.sub.3 N.sub.4 using microwave plasma chemical vapor transport. The films are hard, translucent nanocrystalline films useful for protecting a substrate.

Abstract: Applicant has discovered that aliovalently doped zinc-indium-oxide where In is 40-75% of the metal elements can achieve electrical conductivity comparable to wide band-gap semiconductors presently in use while exhibiting enhanced transparency in both the visible and infrared. The material can be doped to resistivity of less than 1 milliohm-cm by small quantifies of aliovalent dopants, such as tetravalent atoms. It can be deposited on glass substrates in amorphous and polycrystalline films.

Abstract: In accordance with the invention, electronic packages comprising a layer of molded plastic on one side of an insulating substrate are provided with a surrogate layer on the side of the substrate opposite the molded plastic to reduce bending stress. The surrogate layer is preferably thin, has a high coefficient of thermal expansion and is resistant to high tensile stress. Advantageously, the surrogate layer is processed concurrently with the molding of the plastic. Preferred surrogate layers are low temperature thermoplastic sheets, such as acetal plastic sheets, that soften at the molding temperature sufficiently to bond to the substrate. Alternatively, they can be higher temperature rigid materials, such as glass fiber composites, bonded to the substrate with an adhesive layer that cures during molding.

Abstract: A device for transmitting radiation is provided. The device includes a glass optical waveguide having a core. A Bragg grating is at least partially formed within the core. Associated with the Bragg grating is a transmission spectrum that includes a band in which incident radiation is attenuated, the peak attenuation being at a wavelength .lambda.. The transmission spectrum of the Bragg grating is such that the full width at half maximum measured in transmission is greater than or equal to (1.5 nm/1558.5 nm) .lambda. and peak attenuation within the band is greater than or equal to 90% of full scale transmission. Attenuation exceeds 50% of the peak attenuation everywhere within the full width at half maximum of the transmission spectrum.

Abstract: The present invention provides methods and apparatus for making enhanced field emitters by coating particulate substrates with low voltage emissive material such as defect-rich diamond. These methods permit the advantageous, low-cost combination of low voltage emission with sharp-featured geometry.

Abstract: A new method for the manufacture of glass films on substrates involves the flame reaction of an aerosol comprised of droplets of a solution containing all the precursors for the glass. A solution containing the precursors for all oxide components is atomized, and the resulting droplets are reacted in a flame to form spherical glass particles which are deposited on a heated substrate. By moving the substrate through the flame, a homogeneous deposit is achieved. Subsequent heat treatment in a furnace sinters the porous particle layer into a clear glass. The method has been successfully employed for the formation of sodium borosilicate glass films on silicon substrates and rare earth-doped multicomponent glass films for active devices.

Abstract: Recognizing the rate-determining nature of the coating removal and recoating steps, applicants have demonstrated that with proper combination of low absorbing polymer, glass and low intensity radiation, UV-induced gratings can be side-written into polymer coated fibers without removing the polymer, thus permitting up the possibility of high speed fabrication of fiber gratings.

Abstract: The thickness uniformity of a plated metal layer inside a via hole can be enhanced by intersecting a conductive via with an insulating aperture before plating. The new via configuration improves the mass transfer of the plating. It is believed that the apertures lower the local solution ohmic resistance near the via holes. The method can be applied to the manufacture of a wide variety of circuit boards.

Abstract: The present invention is predicated upon the discovery by applicants of a relationship describing thermal decay of radiation-induced index changes and a mechanism which permits stabilization by accelerated aging. Specifically, the induced index change decays in proportion to 1/(1+At.sup..alpha.) where A and .alpha. are functions of temperature, and the decay can be accelerated by heat treatment. As a consequence, the extent of decay can be determined for arbitrary time and temperature and, significantly, an appropriate heat treatment can be scheduled for making a device stable within predeterminable limits.

Abstract: In accordance with the invention a planar waveguide device is fabricated by providing a substrate with an undercladding, depositing a particulate layer of core glass on the undercladding, consolidating the particulate layer by low temperature viscous sintering, patterning the consolidated layer to form an optical waveguide and applying an overcladding. The glass layers can be deposited quickly and economically by slurry dipping, centrifuging or electrophoresis. In a preferred embodiment the substrate is silicon, and the core glass is sodium-boro-silicate.

Abstract: In accordance with the invention, a field emission device is provided with an improved pillar structure comprising multi-layer pillars. The pillars have a geometric structure that traps most secondary electrons and an exposed surface that reduces the number of secondary electrons. Processing and assembly methods permit low-cost manufacturing of high breakdown-voltage devices, including flat panel displays.

Abstract: In accordance with the invention, a new type of monolithic optical waveguide filter comprises a chain of optical couplers of different effective lengths linked by differential delays of different lengths. The transfer of the chain of couplers and delays is the sum of contributions from all possible optical paths, each contribution forming a term in a Fourier series whose sum forms the optical output. A desired frequency response is obtained by optimizing the lengths of the couplers and the delay paths so that the Fourier series best approximates the desired response. The filter is advantageously optimized so that it is insensitive to uncontrolled fabrication errors and is short in length. The wavelength dependence of practical waveguide properties is advantageously incorporated in the optimization. Consequently, the filter is highly manufacturable by mass production. Such filters have been shown to meet the requirements for separating the 1.3 and 1.551 .mu.

Abstract: In accordance with the invention, an electronic device having one or more contact pads is adhered to an array of transferable solder particles on a removable carrier sheet. The carrier is removed, as by dissolving, leaving solder selectively adhered to the contact pads. In a preferred embodiment the solder-carrying medium is water soluble, and the solder particles comprise solder-coated magnetic particles. Application of a magnetic material while the medium is drying or curing, produces a regular array of solder-coated particles. Using this method, devices having smaller than conventional contact structures can be readily interconnected.

Abstract: In accordance with the invention, a field emission device is made by disposing emitter material on an insulating substrate, applying masking particles to the emitter material, applying an insulating film and a gate conductor film over the masking particles and emitter material and removing the particles to reveal a random distribution of apertures to the emitter material. The result is a novel and economical field emission device having numerous randomly distributed emission apertures which can be used to make low cost flat panel displays.

Abstract: In accordance with the invention, a plurality of elongated refractory bodies are laminated together by placing the bodies in close adjacency, exposing the adjacent bodies to a plasma torch heat source, and moving the bodies longitudinal past the torch at a nonzero average rate which includes a reciprocating (e.g., oscillatory) component to longitudinally spread the zone of heating. Where the bodies are a rod to be laminated within a hollow tube, it is advantageous to reduce the air pressure between the rod and tube, thereby eliminating potential contaminants and, at the same time, biasing the tube to collapse against the rod. This method is particularly useful in laminating overcladding tubes to core rods to form optical fiber preforms.

Abstract: In accordance with the invention, a variety of magnetic devices can be made up of two or more low-profile surface components on a printed circuit board. For example, low profile devices comparable to gapped U-core pair and gapped E-core pair inductors or transformers can be formed of two and three components, respectively, and four components can be assembled into a gapped toroidal transformer or inductor. The components can be made in form for both linear and non-linear inductors.

Abstract: We have made the surprising discovery that small amounts of Ag below 1% by weight are effective in making Bi--Sn alloys less strain-rate sensitive without deleteriously affecting the melting character of the alloy. A Pb-free solder composition comprising at least 40% by weight Bi, between 40% and 60% Sn, and between 0.05 and 1% Ag is effective to increase the total elongation of the solder by at least 20% under the same processing conditions. Moreover the solder is free of undesirable Ag-containing phases with a melting point in excess of the 183.degree. C. melting point of the Pb--Sn binary eutectic alloy. In a preferred embodiment, the composition comprises 54.75% Bi, 45% Sn, and 0.25 % Ag.

Abstract: In accordance with the invention, an optical filter comprises a plurality of optical fibers having a coupling region where the axially extending cores are closely spaced within a common cladding. The coupling region includes a long period grating for selectively shifting light of selected wavelengths from guided modes into non-guided modes. These non-guided modes are picked up by an adjacent core and light of the selected wavelengths is thus shifted from one core to another. The result is an optical filter particularly useful as a demultiplexer or a tapping device. In one embodiment the grating is formed in one of the cores. In an alternative embodiment, it is formed in the common cladding.