Abstract: A rapidly-solidified aluminum alloy powder having a nominal composition of 7% Zn, 2.5% Mg, 2% Cu, 0.3% Zr, and 0.3% Cr is used to make a high forming-rate, superplastic, high-strength aluminum alloy. The powder is outgassed, consolidated, and extruded, thereby developing a wide range of particle size distribution of dispersoids in the process, containing respectively zirconium and chromium dispersoids, as well as age hardening precipitates. The consolidated powder is then rolled to 85% reduction to provide a sheet material which is superplastically formed at a temperature in the range of 450.degree. C. to 490.degree. C. and at a rate between 5.times.10.sup.-3 to 5.times.10.sup.-2 per second.

Abstract: A nonlinear optical matrix multiplier includes a nonlinear optical medium with a first optical input beam impinging on the medium, the transverse spatial intensity of the first input beam being modulated by a first two dimensional matrix. A second optical input beam impinges on the medium, with the transverse spatial intensity of the second input beam being modulated by a second two dimensional matrix. An optical probe beam impinges on the medium, the first input beam, the second input beam, and the probe beam being oriented with respect to one another and with respect to the medium such that the beams interact within the medium by means of four-wave mixing. A diffracted output beam emerges from the medium, with the transverse spatial intensity of the output beam modulated by the product of the first and second matrices.

Abstract: A coupled laser system includes a plurality of substantially parallel beams of coherent radiation with an output beam of coherent radiation at an oblique angle with respect to the plurality of beams. A photorefractive element is positioned to receive the plurality of beams and the output beams, the beams being frequency locked to within the photorefractive bandwidth of the photorefractive element such that laser energy is diffracted from the plurality of beams to the output beam by means of two-wave mixing. A lens may be used for focussing the parallel beams in the photorefractive element, while a plurality of mirrors may be supplied for adjusting the orientation of the output beam within the photorefractive element.

Abstract: Electronically excited nitrogen fluoride, NF*, is generated by dissociating fluoride azide, FN.sub.3. In a preferred embodiment, the FN.sub.3 is reacted with vibrationally excited molecules such as hydrogen halide, deuterium halide, carbon dioxide, or nitrogen. In second and third embodiments, the FN.sub.3 is dissociated by laser pumping or by detonation. The NF* can provide a short wavelength laser by pumping the NF(b-X) transition in a resonant chamber or by the addition of an emitting species such as BiF to convert the stored energy of the NF* to photons from the emitting species.

Abstract: An edge illuminated optical detector array includes a series of two or more detectors which operate under an applied electric field. Each detector includes an extrinsic semiconducting active layer with a first conductivity type impurity concentration high enough to create an impurity energy band, and an intrinsic semiconducting blocking layer in which substantially no charge transport occurs by an impurity conduction mechanism. The detectors are positioned relative to one another such that optical energy incident on the array and directed substantially orthogonal to the applied electric field impinges on the first detector in the series and the portion of the optical energy which is transmitted by each detector is directed to the succeeding detector in the series. In this manner, the spectral content of the optical energy impinging on each detector is modified by the spectral transmission characteristics of the preceding detectors.

Abstract: Thermal sources of Te and of Hg are provided in a vacuum chamber to furnish constant effusion of Te and Hg. Laser radiation is used to evaporate a beam of CdTe from a target of CdTe in the chamber. The laser radiation is modulated to vary the beam intensity of CdTe and thereby deposit a controlled compositional profile of Hg.sub.(1-x) Cd.sub.x Te on a substrate located in the chamber.

Abstract: A fiber optic sensor array includes a row of transmitting optical fibers, with a column of detecting optical fibers overlapping the transmitting fibers. A planar compliant spacer separates the transmitting fibers from the detecting fibers, so that a sensor element is defined at each location where a detecting fiber overlaps a transmitting fiber. The surfaces of each transmitting fiber and each receiving fiber are modified at the location of each sensor element to increase the optical coupling between the transmitting fiber and the receiving fiber at that element. The spacer in the array includes an opening between the transmitting fiber and the detecting fiber at the location of each sensor element. A support surface is affixed to the detecting fibers opposite the compliant spacer and a protective cover layer is affixed to the transmitting fibers opposite the compliant spacer.

Abstract: A dual lift-off technique is used to provide self-alignment of the emitter area, the emitter contact, and the base contact of a heterojunction, bipolar transistor. A photoresist pattern which defines an emitter adjacent a base contact is formed on a suitable heterojunction bipolar semiconductor wafer. A base contact is formed by etching through the first semiconductor to the heterojunction and depositing metal on the second semiconductor. Dielectric is then deposited on the base contact. The photoresist is then lifted off with its dual covering of dielectric and metal. The emitter contact metal can then be deposited without requiring critical alignment because the base contact is covered with dielectric.

Abstract: A single-level photoresist process is used to make metal-semiconductor field-effect transistors (MESFETs) having more uniform threshold voltages. An N.sup.- layer is formed in a semi-insulating semiconductor, followed by formation of a dummy gate using a single-level photoresist process. Using the dummy gate as a mask, ions are implanted to form an N.sup.+ region. The length of the dummy gate is then reduced by plasma etching. A dielectric is deposited over the N.sup.+ region, the N.sup.+ /N.sup.- interface, and the exposed portion of the N.sup.- layer. The dummy gate is lifted off to define a self-aligned, submicron gate opening. The gate opening on the N.sup.- layer is reactive ion etched to obtain the desired threshold voltage, and covered with a Schottky gate metal deposit.

Abstract: Disclosed is a detector array for sensing electromagnetic radiation, which is based upon a semiconducting layer of a first conductivity type with an array of junction regions of a second conductivity type located in a major surface thereof. A first insulating layer is deposited over the major surface, and a plurality of conducting plates is disposed on the first insulating layer around each junction region. Each conducting plate creates an induced junction in the semiconducting layer upon the application of an electrical potential between the plate and the semiconducting layer. A second insulating layer is deposited over the plates and the first insulating layer, with a contact through the first and second insulating layers associated with each junction region. Each conducting plate is connected to a control line deposited over the second insulating layer for selectively applying the potential to that plate.

Abstract: Superplastically formable aluminum alloys and composite materials are prepared from rapidly solidified, coarse aluminum powder of a precipitation hardenable alloy, processed to have a low oxide and contaminant content. The powder is mixed, together with reinforcement in the case of the composite material, and then consolidated and extruded at a high extrusion ratio to promote microstructural uniformity and to break up the surface oxide present on the particles. The extrusion is then thermomechanically processed to impart a recrystallized fine-grain aluminum microstructure which is suitable for use in superplastic forming. The unreinforced powder alloy exhibits uniform elongations of over 800 percent at a strain rate of 2.times.10.sup.-4 per second, and a composite having 0.10 volume fraction silicon carbide reinforcement exhibits uniform elongations of over 450 percent at the same strain rate.

Abstract: A method is provided for imparting a very fine grain size to aluminum alloys, including alloys in the form of sheet or heavy sections such as forging billets. The alloy is first aged to form precipitates. The aged alloy is then deformed along its three principal axes in successive operations until a cummulative true strain of at least 8 is achieved.

Abstract: A phase conjugate interferometer includes a source of coherent light and a first beam splitter for dividing the coherent light into a transmitted portion and a reflected portion. A second beam splitter is positioned to divide the transmitted portion into an outgoing transmitted beam and an outgoing reflected beam, with the outgoing transmitted beam oriented to pass through the first image and the outgoing reflected beam oriented to pass through the second image. A phase-conjugate reflector is positioned to reflect the outgoing transmitted beam as a first incoming beam and the outgoing reflected beam as a second incoming beam. The incoming beams are directed toward the second beam splitter, which divides the incoming beams into a first combined beam and a second combined beam. The second combined beam is directed toward the first beam splitter, which divides the second combined beam into a third combined beam and a transmitted beam.

Abstract: A system and method are described for establishing a common operating frequency and phase for the lasers in a two-dimensional array, each of which has an actual frequency which deviates from a common nominal frequency. A waveguide structure is placed in the path of the beams emitted from the various lasers, and a plurality of optical gratings are provided in the waveguide in alignment with the laser beams to deflect portions of the beams into propagation along the waveguide and into cross-coupling with the other lasers in the array. The periodic gratings are characterized by grating periods substantially equal to .lambda./n.sub.1, and the thickness of the waveguide core is at least equal to approximately .lambda./(4.sqroot.n.sub.2.sup.2 -n.sub.3.sup.2), where .lambda. is the wavelength of the guided mode, n.sub.1 is the effective refractive index for the guided mode, and n.sub.2 and n.sub.3 are the refractive indices for the waveguide core and substrate, respectively.

Abstract: A thin film electroluminescent display panel is fabricated by using ion implantation at selected locations in a host layer. By this method, strips of electroluminescent material with different dopants can be created, and these different stripes can be addressed by separate electrodes in order to obtain a multicolor display panel.

Abstract: The thickness t and refractive index n of an incremental thin film layer deposited on a base stack of layers are determined, where the characteristic matrix M of the base stack is ##EQU1## by directing light at a first wavelength toward the layer and the base stack, measuring the reflectance of the first wavelength light from the layer and the base stack, directing light at a second wavelength toward the layer and the base stack, and measuring the reflectance of the second wavelength light from the layer and the base stack. The measured values of reflectance for each wavelength are then substituted in the relationship ##EQU2## whereB.sub.1 =M.sub.11 Cos.phi.-(M.sub.21 /n) Sin.phi.,B.sub.2 =N.sub.s (M.sub.12 Cos.phi.+(M.sub.22 /n) Sin.phi.),C.sub.1 =N.sub.s (M.sub.22 Cos.phi.-M.sub.12 nSin.phi.),C.sub.2 =M.sub.11 nSin.phi.+M.sub.21 Cos.phi.,.phi.=2.pi.nt/.lambda.,N.sub.s is the refractive index of the substrate, and.lambda. is the wavelength at which the reflectance is measured.

Abstract: An apparatus for compressing the spectral distribution of a coherent beam of light includes a narrowband filter for separating the coherent beam into a transmitted portion containing optical energy substantially limited to a single wavelength .lambda. and a reflected portion containing the remainder of the coherent beam. A photorefractive crystal is positioned to receive the transmitted and reflected portions. A mirror deflects the reflected portion toward the photorefractive crystal. The photorefractive crystal is oriented such that two-wave mixing within the crystal causes a substantial portion of the energy in the reflected portion to be converted into optical energy at the wavelength .lambda. and to emerge from the crystal in the direction of the transmitted portion. The spectral bandwidth of the coherent beam is less than 1/.tau., where .tau. is the holographic time constant of the photorefractive element.

Abstract: Disclosed is an apparatus for depositing a layer of a material on a substrate and annealing the deposited layer, including a Q-switched Nd: YAG laser for providing a coherent light output. An up collimator is situated in the path of the coherent light output to increase the cross sectional area of the output, while a beam divider separates the output into first and second coherent beams. First and second lenses are adjustably positioned in the paths of the beams to focus the first beam on a source of the material and the second beam on the substrate. First and second x-y scanners are provided for scanning the first and second beams. A vacuum chamber includes a connection for a vacuum source and windows to admit the first and second beams into the chamber. A source support positions a source of the material within the chamber in the path of the first beam and a substrate support positions the substrate in the path of the second beam and at least 45.degree. away from the normal to the surface of the source.

Abstract: A method of adjusting the threshold voltages of field effect transistors fabricated on a III-V compound semi-insulating wafer includes the steps of measuring the threshold voltages of the transistor, directing an ion beam at the wafer to selectively damage the channels of the transistors, thereby shifting the threshold voltages to an interim value, and annealing the wafer at a temperature and for a time sufficient to stabilize the threshold voltages at a predetermined optimum value determined by the intensity and duration of the ion beam implantation. The III-V compound semi-insulating wafer may be GaAs. The ion beam may be supplied as protons accelerated to approximately 320 KeV with a concentration of between approximately 10.sup.11 and 10.sup.13 protons/cm.sup.-2. The wafer may be annealed at a temperature from approximately 100.degree. C. to approximately 300.degree. C. (for approximately one half hour at 300.degree. C.

Abstract: A process for producing novel oxy-metallo-organic, e.g. oxy-alkoxy, polymers is disclosed which comprises heating a metallo-organic compound, e.g. an alkoxide of a metal selected from the group consisting of aluminum, titanium and zirconium, and mixtures thereof, such as aluminum butoxide, under reflux in inert atmosphere and in the absence of any solvent, and polymerizing the metallo-organic compound. The resulting polymer can be in the form of a viscous liquid, a glass or an amorphous powder, and can function as intermediates or precursors for production of ceramics, ceramic composites, fibers and films.