Abstract: An optical memory cell constructed from an optical combiner, a 1.times.2 optical swtich and optical fibers. One input port of the optical combiner serves as the input to the memory cell. The output port of the optical combiner is connected to the input of the optical switch by an optical fiber. A first output port of said switch is connected by an optical fiber to the second input of the optical combiner, such that when said switch is in the straight-through state, an optical loop is formed through which an optical pulse can circulate. The second output of the optical switch serves as the output of the memory cell when said optical switch is in the cross-over state. Control signals are provided by a clock.

Abstract: A method for fabricating a microelectronic device of the metal/insulator/metal' type wherein the insulator is an organic material, and a device fabricated thereby. A first electrically conductive lead is conductively adhered to a first portion of a conductive substrate. A monomolecular layer of highly pure p-dodecyloxyphenylcarbamate of 2-(2'-hydroxyethoxy)-5-bromo-7,7,8,8-tetracyanoquinodimethan is deposited on a surface of a second portion of the conductive substrate not including the first portion to form an organic film. Molecules of the monomolecular layer are generally disposed normal to the substrate surface with their dodecyl terminal moieties adjacent the surface. An essentially oxide-free contiguous layer of magnesium is deposited on the organic film. The deposition is performed at a temperature below about 15.degree. C. A layer of silver is deposited on the magnesium layer to substantially cover and conductively adhere to the magnesium layer.

Abstract: The present invention describes an improved collet grip for holding tensile bars during testing. The collet includes a 90.degree. concave surface to match the machined tensile bar thereby improving the gripping action. The collet also has a taper on the inside diameter to compensate for any allowable taper in the machining process.

Abstract: A process for sealing of niobium-ceramic through-wall assemblies for ceramic or metal vessels for high temperature and high pressure or vacuum applications, for example an electrical feedthrough and sealable fill opening in an alumina arc tube for a high intensity discharge (HID) lamp. The process produces a fritless hermetic seal while maintaining the ductility of the niobium components. The niobium-ceramic through-wall assembly includes an axially bored alumina or yttria sealing means having a ductile niobium throughpiece close fitted to and extending through the bore. The throughpiece is preferably essentially pure niobium, but may contain up to about 2% zirconium. The assembly is fired at about 1400.degree.-2000.degree. C. in a pure oxygen- and hydrogen-free (<5 ppm each) inert, preferably flowing, atmosphere or vacuum for a time sufficient to form a hermetic seal between the throughpiece and the sealing means. The fired assembly is then cooled to below 250.degree. C.

Abstract: A new and improved bonded ceramic-metal article and the method of making the article is described. The ceramic-metal article comprises a ceramic article, such as a lanthana-strengthened yttria article, bonded to a metal article, such as niobium, by a layer of a brazing material to form a bonded ceramic-metal article. The method of bonding the ceramic article to the metal article comprises placing the brazing alloy, such as a brazing alloy consisting essentially of 63% by weight silver, 35.25% by weight copper, and 1.75% by weight titanium, between the lanthana-strengthened yttria article and the niobium article and heating the layered structure in vacuum at about 50 degrees centigrade above the liquidus temperature of the brazing alloy for a period of about 5 minutes.

Abstract: A method and device for continuously monitoring the distributed high voltage pulses from an ignition coil of an electrical system of an internal combustion engine is disclosed. The device is a transparent enclosure filled with a noble gas at low pressure. The inner wall of the enclosure is coated with a light emitting phosphor and a small amount of mercury is placed within the enclosure. When the device is placed near a high voltage wire, an electric field capacitively couples to and ionizes the gas within the device. The mercury is excited and emits photons of ultraviolet radiation which in turn creates visible light as the ultraviolet radiation excites the phosphor coating. When this device is placed next to a spark plug wire, it will illuminate when there are high voltage pulses in the wire. In a preferred embodiment two or more enclosures are placed near the same wire. The enclosures contain different gas pressures and are excited at different voltages.

Abstract: An IMSM photodetector structure comprises a GaAs substrate, a buffer region grown on the substrate, an optically active absorbing layer of In.sub.0.42 Ga.sub.0.58 As grown on the absorbing layer. The buffer region includes in sequence a first layer of In.sub.0.23 Ga.sub.0.77 As, an In.sub.0.46 Ga.sub.0.54 As/GaAs superlattice, and a second layer of In.sub.0.23 Ga.sub.0.77 As. An interdigitated pattern of Schottky metal contacts is fabricated on the Al.sub.0.3 Ga.sub.0.7 As/GaAs superlattice. This structure is useful in fabricating long-wavelength, monolithic receivers based on GaAs MESFET technology since the optical and electrical characteristics of the structure are preserved during the thermal annealing cycle necesary in ion-implaned GaAs MESFET processes.

Abstract: A dense cermet article including about 80-90% by volume of a granular hard phase and about 5-20% by volume of a metal phase. The hard phase is a carbide, nitride, carbonitride, oxycarbide, oxynitride, or carboxynitride of a cubic solid solution selected from W-Ti, W-Hf, W-Nb, W-Ta, Zr-Ti, Hf-Ti, Hf-Zr, V-Ti, Nb-Ti, Ta-Ti, or Mo-Ti. The metal phase consists essentially of a combination of nickel and aluminum having a ratio of nickel to aluminum of from about 90:10 to about 70:30 by weight, and 0-5% by weight of an additive selected from titanium, zirconium, hafnium, vanadium, niobium, tantalum, chromium, molybdenum, tungsten, cobalt, boron, and/or carbon. The preferred hard phase is a cubic solid solution of tungsten and titanium. In the preferred metal phase, an amount of about 15-80% by volume of the metal phase component exhibits a Ni.sub.3 Al ordered crystal structure. The article may be produced by presintering the hard phase - metal phase component mixture in a vacuum or inert atmosphere at about 1475.

Abstract: A video system includes a central facility and a terminal. Means are provided for playing a video recording medium storing a video program including a series of television fields including a first field containing both a random digital code encrypted according to a code encryption key and program identification data, and a second field containing an unintelligible video signal previously transformed from a intelligible video signal according to the random digital code. The terminal includes means for sending the program identification data to the central facility. The central facility includes a data base for storing and retrieving at least one code encryption key corresponding to the program identification data and means for sending the code encryption key from the central facility to the terminal.

Abstract: The method of making a bi-layer coating on phosphor particles is disclosed. The first layer surrounding the phosphor is silica. The second layer surrounding the phosphor is alumina. The bi-layer phosphor is useful in fluorescent lamps providing improved maintenance and brightness. The bi-layer phosphor can also be used in high color rendition lamps employing blends of phosphors.

Abstract: A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength. The powder mixture includes 9a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon mitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12m.sup.2 g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified articel an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid.

Abstract: A broadband switching matrix having M.times.N crosspoint switches is arranged into a selected number of groups of vertically cascaded stages in which adjacent groups are interconnected with expansion stages. An input signal switched from row to column in a particular group propagates through the remaining stages in that group and then propagates successively through the expansion stages in each following group before reaching an output port. In another array configuration, a set of N multiplexers arranged in parallel each receive N input signals and provide a single output signal at a respective output port. The multiplexers are constructed from 2:1 selector elements which are arranged in a vertical tree configuration having log.sub.2 N cascaded stages. Each multiplexer has the same number of stages and hence selector elements. Both broadband switching arrays are designed so that each switch drives only one other switch in the array, thereby minimizing capacitive loading and maximizing propagation speed.

Abstract: Disclosed is a method for applying a continuous protective coating to the surface of individual phosphor particles. The method involves chemical vapor deposition of an aluminum oxide coating on individual particles of a phosphor powder while the particles are suspended in a fluidized bed. The particles in the fluidized bed are exposed to vaporized coating precursor material, preferably aluminum isopropoxide at a temperature above 300.degree. C. The bed is kept at as nearly an isothermal condition as possible. Prior to entering the fluidized bed the aluminum isopropoxide is vaporized and kept at a temperature less than the decomposition temperature of aluminum isopropoxide. Mechanical means are used to help increase the fluidization efficiency of the fluidized bed. After coating the phosphor particles for approximately 30 minutes the vaporized precursor material is shut off from the bed entrance and the oxygen flow rate to the fluidized bed is increased.

Abstract: A process for producing a silicon nitride-based article of improved fracture toughness and strength. The process involves densifying to at least 98% of theoretical density a mixture including (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 .mu.m and a surface area of about 8-12 m.sup.2 /g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 .mu.m and a surface area of about 2-4 m.sup.2 /g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid.

Abstract: Method of forming a fluorinated silicon nitride film on a semiconductor substrate by first forming a coating of ammonium hexafluorosilicate on the electrode of a plasma reactor to serve as a source of fluorine during the silicon nitride deposition procedure. The ammonium hexafluorosilicate coating is formed by generating a plasma of carbon tetrafluoride and oxygen within the reactor, then a plasma of nitrogen, followed by a plasma of silane and helium with nitrogen. The substrate is then placed in the reactor and a plasma employing silane and helium together with nitrogen is generated at low RF frequency to produce a fluorinated silicon nitride film on the substrate.

Abstract: Electrical circuitry providing a compatible interface between ECL logic level of -1.6 and -0.8 volts and CMOS logic levels of 0 and +5 volts. Voltage sources of -3.7 and +1.3 volts are provided for supplying operating voltages to the CMOS circuitry in order to set the threshold voltage CMOS inverters at -1.2 volts, the threshold voltage of ECL logic circuits.

Abstract: A video recording medium storing a video program includes a series of television fields including a first field containing both a random digital code encrypted according to a code encryption key and program identification data, and a second field containing an unintelligible video signal previously transformed from an intelligible video signal according to the random digital code.

Abstract: A video system includes a central facility and a terminal. Means are provided for transmitting to the terminal a video program including a series of television fields including a first field containing both a random digital code encrypted according to a code encryption key and program identification data, and a second field containing an unintelligible video signal previously transformed from an intelligible video signal according to the random digital code. The terminal includes means for sending the program identification data to the central facility. The central facility includes a data base for storing and retrieving at least one code encryption key corresponding to the program identification data and means for sending the code encryption key from the central facility to the terminal.

Abstract: A method for manufacturing a dense cermet article including about 80-95% by volume of a granular hard phase and about 5-20% by volume of a metal binder phase. The hard phase is (a) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, carboxynitrides, borides, and mixtures thereof of the elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and B, or (b) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, and carboxynitrides, and mixtures thereof of a cubic solid solution of Zr--Ti, Hf--Ti, Hf--Zr, V--Ti, Nb--Ti, Ta--Ti, Mo--Ti, W--Ti, W--Hf, W--Nb, or W--Ta. The binder phase is a combination of Ni and Al having a Ni:Al weight ratio of from about 85:15 to about 88:12, and 0-5% by weight of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Co, B, and/or C. The method involves presintering the hard phase/binder phase mixture in a vacuum or inert atmosphere at about 1475.degree.-1675.degree. C., then HIPing at about 1575.degree.-1675.degree. C.

Abstract: A new and improved method of treating a manganese activated zinc silicate phosphor is described. The method comprises heating a manganese activated zinc silicate phosphor powder having cations consisting essentially of zinc, silicon, manganese, and tungsten and having a 350 nm reflectance less than 80% and a 275 nm reflectance greater than 13.5% to a temperature of about 1225.degree. C. in air. The phosphor powder is then cooled to room temperature and wet milled in an acid solution. The phosphor powder is then separated from the acid solution washed in water and dried to form a dry phosphor powder having a 350 nm reflectance equal to or greater than 80% and a 275 nm reflectance equal to or less than 13.5%.