Abstract: Many prior art bistable optical devices require resonant optical cavities and are therefore limited in their operation due to the long lifetimes associated with their high-finesse cavities. A bistable optical device that does not use a resonant cavity is disclosed wherein a nonlinear medium whose index of refraction increases with increased light intensity is arranged to have input and output faces into which and out of which a laser beam having a nonuniform spatial profile can be propagated. A mirror having a predetermined area of reflectivity is positioned with respect to the output face of a nonlinear medium so as to reflect only the light energy that propagates in an area at the output face that is approximately equal to the area which the beam presents at this face when the beam is propagating at a critical power level, that is, when the beam is self-trapped.

Abstract: The use of polymers including an indanone entity for use as a resist in a photosensitive body used in a lithographic process leads to desirable results. These resists have excellent resolution essentially equivalent to that obtainable with poly(methyl methacrylate). Additionally, the sensitivities of these polymers to the actinic radiation typically used in photolithographic processes, e.g., radiation from a mercury lamp, is significantly better than that obtained with poly(methyl methacrylate).

Abstract: A protection circuit for communication equipment connected to a two conductor communication line includes a bridge rectifier having alternating current terminals connected to the conductors and to ground. The direct current terminals of the rectifier are connected to a device responsive to a range of predetermined voltage and current conditions in the conductors for reflecting foreign electrical energy.

Abstract: In a fabrication sequence for VLSI MOS devices, an advantageous alignment mark for a wafer to be directly processed by electron beam lithography is made of tantalum disilicide protected by a silicon nitride layer.

Abstract: Semiconductor lasers and LEDs are described in which the pumping current is constrained to flow from a relatively narrow upper channel formed by a V-groove, which extends to a depth short of the active region, through a relatively wider lower channel bounded by high resistivity regions, which extend from at least that depth into or through the active region. Also described are devices in which the V-groove is refilled with semiconductor material.

Abstract: Switching between optical fibers is achieved through the use of a fixed (101) and a moveable (102) housing disposed within a slotted support member (103, 205). The fixed and moveable housings respectively contain first (104, 105) and second (108) sets of optical fibers. Each housing has two grooved (204) and parallel exterior surfaces. Both housings are disposed in substantial abutment to one another in the slotted support member with both sets of optical fibers parallel to one another. The sidewalls of the slot are grooved to be the mating opposite of the grooved housing surfaces. The first housing is fixedly positioned in the slot by the mutual engagement of the grooved exterior housing surfaces and the grooved sidewalls. Switching between optical fibers is accomplished by the translation of the moveable housing surfaces to either of two positions which axially aligns a predetermined number of optical fibers in the first and second sets.

Abstract: An integrated circuit voltage reference (V.sub.REF) for MOS circuit utilization is supplied by the weighted difference amplification (30) of the voltages (V.sub.1, V.sub.1 ') developed by a pair of separate similar networks (10, 10' or 100, 100') each of which comprises a base-emitter junction of a bipolar semiconductor transistor (T.sub.1) whose emitter is connected to a first clocked voltage source (C.sub.1, C.sub.2, M.sub.1, M.sub.2) in a feedback loop of a difference amplifier (A.sub.1) and whose collector is connected to receive output of a second clocked voltage source (C.sub.3, C.sub.4, M.sub.3, M.sub.4) and to deliver output to a first input terminal of the difference amplifier (A.sub.1). In a preferred embodiment, a second input terminal of the difference amplifier (A.sub.1) is supplied by the output voltage of an auxiliary voltage source (C.sub.5, C.sub.6, M.sub.6, M.sub.7, M.sub.8, M.sub.9) which is in another feedback loop of this amplifier (A.sub.1).

Abstract: A method of making flexible composite piezoelectric materials exhibiting hydrostatic response and having a stable response over time is given. A prepolymer material is combined with a piezoelectric material and polarized by applying an electric field while inducing an electric dipole in the piezoelectric material, typically by applying hydrostatic pressure or changing the temperature. To ensure stable response characteristics, the polymer material is chosen to have a shear modulus of less than 20 pounds per square inch. To help ensure good contact between the piezoelectric material and the polymer material, controlled shrinkage may be induced in the composite materials by heat or the removal of a volatile material. The prepolymer material desirably has an electrical resistivity greater than 10.sup.10 ohm/meters. Typical piezoelectric materials include lithium sulfate and tartaric acid. Typical polymer materials include RTV rubber, urethanes, and polybutadienes, and may be in the form of oligomers.

Abstract: Disclosed is a method of improving the coating on electrodes (11 and 12) in spark gap devices which minimizes filament formation, densifies the coating, and ensures a good bond between the coating and underlying electrode. The device is coupled to a circuit (FIG. 2) which includes appropriate components so that a rapid sequence of current pulses having large amplitudes during arc initiation is passed through the device. The coating bonds with a different area of the cathode for each current pulse. The signal may be applied with appropriate reversal of polarities so that essentially the entire surface of both electrodes is thus reacted. Subsequently, the device may be subjected to an additional pulse in order to leave asperities on the surface which will increase field emission and ensure a low surge limiting voltage.

Abstract: A communication method and switching system in which voice and data signals are communicated through the system by a programmed controlled switching processor. The switching processor reads these signals from an input memory where they were transferred from telephone stations and data terminals by a scanner. The voice and data signals are transmitted to telephone stations and data terminals by the switching processor storing these signals in an output memory from which they are retransmitted by a distributor to the telephone stations and data terminals. The intelligent processor reads data signals from the input memory and assembles these signals into data packets which are temporarily stored in the data memory. Subsequently, the intelligent processor transmits these data packets by storing the data signals in the output memory.

Abstract: A fabrication technique is described for making various devices in which a certain type of glass is used as a surface protection layer. The glass layers are formed by particle bombardment (generally sputtering or E-beam) of a glass target. Devices with such surface layers are also described. Such glass layers are highly advantageous as encapsulating layers, diffusion barrier layers, etc., particularly for optical type devices and certain semiconductor devices. Particularly important is the preparation procedure for the glass target used in the bombardment process. The glass layers are moisture stable, act as excellent barriers against diffusion, and are usable up to quite high temperatures (i.e., in diffusion doping procedures) without cracking or peeling. The glass layers also provide long-term protection against atmosphere components including water vapor, oxygen, atmosphere pollution contaminants, etc., and can be removed by standard etching techniques.

Abstract: A data control circuit (18) for an input/output arrangement is arranged for controlling the transfer of a data word through a shift register (20 or 120) to or from a peripheral device (22 or 122). The circuit (18) provides for selection between internal clock generation at one of several rates or application of an external clock and for selection of the length and format of the data words to be transferred. Selection is accomplished by an interval counter (38), format data stored in a control register (37), two gating circuits (30 and 40) and a selection circuit (35).

Abstract: The data transmission rate link length product of monomode fiberguide telecommunication systems can be increased above values possible in "linear" systems by appropriate use of the non-linear dependence of the fiber refractive index on electric field. In particular, selecting the appropriate pulse peak power and center wavelength can result in creation of a soliton, i.e., a pulse capable of substantially dispersionless transmission. The center wavelength is to be close to, but larger than, the wavelength of zero first-order chromatic dispersion of the fiberguide, and the latter wavelength is to be within the anomalous dispersion regime of the fiberguide. Criteria for determining the appropriate peak power, center wavelength, fiber loss, and minimum link length, as well as the asymptotic pulse width and soliton spread due to the power loss in the fiber are given, and facilitate design of a system according to the invention.

Abstract: Alloys comprising copper, nickel and tin, when appropriately processed, exhibit high levels of tensile strength and ductility. Processing has been by cold working and aging or, when cold working is impracticable, by aging of alloys which are modified by the addition of a refractory element.It has been discovered that, even without cold working and even in the absence of additives, strong and ductile Cu-Ni-Sn alloys can be produced when a body of the alloy is subjected to a characteristic heat treatment to develop an alpha plus essentially nonlamellar gamma structure. This is followed by cooling and aging at a temperature and for a time corresponding to a predominantly spinodal alpha-1 plus alpha-2 structure.Typical properties are a 0.01 percent offset yield strength of 128 Kpsi and an elongation to fracture of 5 percent in an alloy comprising 15 weight percent Ni, 8 weight percent Sn, and remainder essentially Cu.

Abstract: Crystal grain size in a material is increased by scanning the material with an appropriately directed energy beam. Short-term oscillation in the scan, and a particular temperature gradient configuration in the wake of the scan, results in growth of large-grain crystallites.

Abstract: Energy in a received signal is distinguished as being whole band energy or partial band energy by comparing an average value of the received signal to a modified magnitude value of the received signal. When the modified magnitude value exceeds the average value, the received signal includes whole band energy, otherwise the received signal includes only partial band energy.

Abstract: Electrical connector testing apparatus for detecting obstructions in the connector contact terminal pin receptacle channels caused by defective receptacle blades (18, 19). A carriage (22) for retaining a connector (20) in an upright position is movable between upper and lower horizontal members (40, 41) of a detection frame (36) to position the contact receptacles (16, 17) row by row between corresponding pairs of light emitting diodes and phototransistors (45, 44) fitted respectively in the horizontal members (40, 41). Light beams generated by the diodes (45) pass unobstructed through properly fitted contact receptacles (16) and are interrupted by receptacles (17) having defective, bent blades. The phototransistors (44) detect the unobstructed light beams and transmit signals indicative of properly fitted receptacles (16) to control circuitry (65), which may conveniently comprise a microprocessor, which may then be programmed to initiate appropriate action for the identification of the defective connector.

Abstract: A microprocessor system that provides protection against memory violations by interrupting the central processing unit (CPU). A problem arises when the interrupt itself causes memory violations in push-down stack operations. This problem is solved by providing an auxiliary memory to store stack overflow data. Memory violations are detected (30, 40) and overflow data is written (42, 60, 33, 100) into auxiliary memory, at sequential locations (50, 51, 60). An interrupt signal is returned (30, 20) to the CPU. A stack overflow interrupt program reads the number of locations written (50, 80, 90), and accesses the auxiliary memory (100, 60, 70, 90) to determine and correct the cause of the overflow.

Abstract: Disclosed is a method of coating electrodes in spark gap devices which minimizes filament formation. A coating (21) such as carbon is deposited on the electrode surfaces (11 and 12). A signal is then applied so that the device conducts in the arc mode for several short periods. A small spot of the coating bonds with the negatively biased electrode during each conduction. This operation continues at alternating polarities until essentially the entire surface area of both electrodes is bonded.