Abstract: An integrated optical waveguide structure which provides for efficient, single-mode propagation of light across an interface between two contiguous waveguide layers of differing effective refractive index. The waveguides are formed by layers of increased index of refraction formed at the surface of a substrate and serve to support propagation of optical electromagnetic radiation along the surface of the substrate. A refractive interface is provided at the interface of two such surface layers supporting modes of differing effective indexes of refraction. By underlying one of the surface layers with an additional layer having a particular, but different, index of refraction, a single mode of propagation is supported throughout both of the surface waveguides. General applications in the formation of optical waveguide components as well as a more extensive treatment with the formation of a lens is also disclosed using proton exchange in crystalline LiNbO.sub.3.

Abstract: An apparatus for forming a braided covering over an article, such as a wire harness, which is continuously operable for forming a braided covering throughout the entire length of the wire harness. A sensor, operable in response to movement of the material being utilized for forming the braided covering, is actuable to control the operation of a mechanism for advancing the braided harness out from the zone of braiding operation to permit the continuous braiding of the harness throughout the length thereof. A detector, operable in response to the presence of deformations in the braided harness, controls operation of the advancing mechanism and braiding operation to detect, for example, breaks in the threaded material being supplied for the braiding operation.

Abstract: A process continuously deposits a carbonaceous film, by chemical vapor deposition, onto a moving longitudinally extending web of a plurality of matted or woven fibers, a plurality of parallel individual fibers, or a bundle of fibers, of a refractory ceramic or refractory vitreous material. The result is a coated web having a controllable resistance along its length and a substantially uniform resistance across its breadth. An organic precursor is directly applied to the web in liquid and/or solid form, the applying being at a temperature below sublimation, boiling or decomposition temperature of the precursor. The web is continuously moved through a hot chemical vapor deposition zone at a temperature of 800.degree. C-1200.degree. C., the zone being substantially oxygen-free, the residence time of each portion of the web within the zone being less than that which would deleteriously effect the properties of the resulting carbonaceous film coated web.

Abstract: A method of forming a composite metal-ceramic helix structure suitable for TWT application. The method includes concentrically joining a metal cylinder disposed within a ceramic cylinder to form a high strength hermetic bond therebetween having good thermal conductivity. Prior to joining the cylinders a predetermined quantity of heat vaporizable liquid is disposed within the metal cylinder and its ends are sealed off. During the brazing process the liquid vaporizes ensuring intimate contact between the concentric cylinders. Thereafter the metal cylinder ends are removed and the resulting concentric structure machined into a helical shape.

Abstract: Method and apparatus for reducing aerodynamic drag and enhancing lift by using ultrasound to alter the structure of boundary layers. In one embodiment, a continuous thin sheet of ultrasound is radiated transversely into the boundary layer parallel to an aerodynamic surface, such as an aircraft wing, carrying that boundary layer.To ensure that the ultrasound sheet remains under (or over) the wing, means are provided to compensate for any downstream drift of the sheet with wing flow by transmitting it in a forward direction in proportion to the Mach number of the flow. The ultrasonic sheet may be applied as periodic strips spaced at predetermined downstream intervals.In order to decrease the amount of acoustical energy required to implement the techniques of the present invention and to operate in a more efficient manner, the ultrasound transmission is modulated with audio frequencies.Means for tuning the audio frequency to match various flight conditions are provided.

Abstract: In a ring laser gyroscope the sum and the difference of the two opposed beam intensities is utilized, in a first implementation, to correct gain non-linearity, and in a second implementation, to adjust tuning mirror positions to minimize non-linear gain output. In a third implementation one or two external mirrors can be used to feed back into the cavity to produce linear gain output, again using the sum and difference of the two opposed beam and the phase angle between the two beams. Accordingly, the sum and the difference of the beam intensities and their phase angle is used to compensate for the laser gain and loss dependent terms and for the back-scattering terms which heretofore have been caused errors in the readout.

Abstract: Auxiliary aeroelastic control flaps arranged on the leading edge of an aircraft's wings at or near the wing tips and ahead of the ailerons for actuation under control of the pilot. The aeroelastic control flaps operate with the ailerons to induce supplementary aerodynamic force to augment the effectiveness of lateral and directional control during high stress manuevers at high dynamic pressures, but do not rely on wing sensors such as accelerometers coupled with a computer for automatic operation.

Abstract: Described herein is an integrated acousto-optic circuit for analyzing the spectrum of a radar signal. A waveguided optical beam is first split into two parts, one of which interacts with a surface acoustic wave generated by a reference signal and the second of which interacts with a surface acoustic wave generated by the signal to be analyzed. The two resulting phase-modulated optical waves then are recombined, Fourier transformed by a lens and finally caused to impinge on an array of photodetectors. The array of detectors is arranged so that each element of the array responds to the combination of one component of the time-varying signal to be analyzed and one component of the time-varying reference signal, that response being an output signal at some preselected radio frequency which is proportional to the amplitude of the frequency component of the radar signal to be analyzed. The several optical components are disclosed as formed on a single substrate integrated optical circuit.

Abstract: A releasable fastening device for securing workpieces together in a firm and intimate relationship is disclosed. The fastening device is sometimes referred to as a "blind fastener". The fastener comprises a bolt member including a head located on one end of the bolt and extending outwardly therefrom to support an upper workpiece and a shank with an annular recess, the shank being insertable within said through axially aligned apertures located in the workpieces. An expandable device, preferably in the form of a stiff spring is inserted and is confined within the annular recess. When the spring is in its expanded position, it extends beyond the shank along a bottom surface of a lower workpiece thereby along with the head on the bolt member holding the workpieces together in a mating relationship.

Abstract: An improved railgap switch for use with pulse discharge gas lasers. The blade of the prior art railgap switches is replaced by an electrode having an "T" shaped cross section which provides two edges along which arcs are generated. The thickness of the "T" cross section near the edges at which arcs are formed is relatively uniform and oriented at a constant distance from the second electrode so that the thickness and distance remains unchanged despite ablation of the edges of the electrode. As a consequence the electrical properties of the switch are not altered significantly by ablation caused by repetitive operation of the switch.

Abstract: A flexible electrically conducting cloth is described which comprises a plurality of intermingled or interwoven refractory fibers the sheet resistance of which exceeds 1,000 ohms per square inch and a conducting coating encapsulating a majority of the fibers, the coating including at least about 70 atomic percent carbon and being applied in sufficient quantity to render the cloth electrically conducting with a sheet resistance which lies between about 0.1 ohm per square inch and about 1,000 ohms per suqare inch. The cloth is useful as an electrical resistance heater, an electromagnetic shield, an electromagnetic reflector, or as an antenna. It is formulated by contacted substantially the entire surfaces of the intermingled or interwoven fibers with a carbon containing precursor, the fibers being at a temperature between about 700.degree. C. and 1200.degree. C., whereby the fibers are covered with a pyrolyzed coating formed from the precursor in an amount of at least about 0.001 weight percent.

Abstract: A conductive polymer is set forth which comprises a plurality of interconnected units. Each unit comprises a generally centrally positioned moiety and a ligand or set of ligands having a total dentation capability of three or more non-coplanar dentations and being positioned about the centrally positioned moiety, at least two of the dentations being parts of conjugated systems. The units are interconnected by having at least one ligand in common and the conjugation of the conjugated systems extend from one centrally positioned moiety to an adjacent centrally positioned moiety. Through proper selection of ligands and centrally positioned moieties, conductive polymers of various desired characters including intrinsically conductive polymers, p-type semiconductor polymers, n-type semiconductor polymers, p-type metal conducting polymers and a n-type metal conducting polymers can be constructed.

Abstract: A device utilizing lasers wherein efficient wavelength shifting of the generated laser radiation is provided using stimulated Raman scattering both in atomic vapor and molecular media. A coupled pair of confocal unstable resonators in conjuction with an integral injection laser is utilized in a novel optical arrangement for providing the efficient conversion of laser power into Stokes radiation without beam obscurations. The wavelength, spectral bandwidth, polarization and beam divergence are controlled by the spatial evolution of the main laser output which is locked to the seed radiation provided along the optical axis by the injection laser. Mode matching of the wavefront is automatically achieved by the use of common optical surfaces which couple the injection laser, main laser and the Raman converter. The resulting Stokes output through a partially reflecting/transmitting mirror is an unobscured beam whose intensity profile is determined by the laser medium power distribution.

Abstract: Heated superplastic material is deformed using gas pressure which forces the material into a die cavity. Improved three dimensional models for deforming superplastic materials are based upon spherical shapes penetrating the die cavity which is approximated by one of two different rectangular box models. The three dimensional and box models produced radius and thickness equations from which an accelerated gas pressure versus time profile and a minimum thickness value are calculated. The gas pressure deforms the superplastic material at the maximum possible strain rate without rupturing thereby reducing the speed at which parts are formed. Die frictional effects and variable flow stress phenomena are included into the pressure versus time profile computation and thickness equations so as to improve the speed and accuracy of the superplastic forming process.

Abstract: The present invention provides a Ram airbreathing laser adapted to use with an aircraft which operates primarily in the Mach 3 to Mach 6 regime. Valves, or gates, are provided in the propulsive flow path and the auxiliary flow path for laser in a manner such that the air entering the aircraft engine inlet duct system is either directed to the laser or to the propulsive flow path depending upon the desired mode of operation of the aircraft.

Abstract: The present invention provides a single seat aircraft having the capabilities of vertical takeoff, landing and hovering operations utilizing the X-Wing as a conventional helicopter rotating wing. After transition to forward flight following takeoff, the rotating wing is stopped and becomes a fixed wing of "X" configuration. The aircraft utilizes two engines within the fuselage, one engine being positioned vertically above the other along the longitudinal axis of the aircraft, the particular arrangement of engines allowing aircraft size and weight to be substantially reduced.

Abstract: Methods are disclosed for the manufacture of optical conductive transparent windows and coatings having high transparency over a wide bandwidth combined with a large acceptance angle of incidence. Particulars for making windows and coatings with gold films of high transparency and low sheet resistance using specified nucleating and barrier layers are given. Examples include windows and coatings constructed for operation in the infrared and ultraviolet.

Abstract: A ring laser gyroscope incorporates a resonant cavity generally shaped as an irregular pentagon having a portion thereof conformed as three legs of a rectangle closed by two symmetrical other legs to form an apex. As result the enclosed area is increased, increasing sensitivity and decreasing lock-in, while magnetic effects are reduced. Additionally, the irregular shape allows for the extension of the gain medium which therefore increases the effectiveness thereof.