Abstract: An optics assembly for observing a panoramic scene comprises a plurality of optical elements. A flat reflective element redirects light from a panoramic scene. A plurality of refractive elements, successively receive the redirected light from the reflective element and create a real pupil. An optical relay system receives light from a last of the plurality of refractive elements. The optical relay system establishes the focal length of the optics assembly, corrects optical aberrations produced at the real pupil, corrects field aberrations and produces an annular image on a flat focal plane assembly. The optics assembly produces a small F-number at field angles perpendicular to the optical axis of the optics assembly over a panoramic scene.

Abstract: A V-shaped singlet delta oxygen manifold for a chemical iodine oxygen laser wherein singlet delta oxygen is produced in one or more reaction zones and enters the interior of the V-shaped manifold. The V-shape of the integral manifold causes the singlet delta oxygen containing gas to undergo rapid change in flow area and a consequent rapid increase in velocity. The integral manifold also directs the singlet delta oxygen entering the V-shaped manifold to the open end of the V which is connected to a nozzle for injecting singlet delta oxygen into a laser cavity for providing energy to a laser beam. The V-shape enables a uniform pressure along its arms for introducing the singlet delta oxygen to the inside of the singlet delta oxygen manifold and directs the flow of the singlet delta oxygen to the nozzle.

Abstract: A process for enhancing the bond strength of resistance welded joints between titanium alloy articles includes a first step of resistance welding two titanium alloy articles and a second step of heat treating the resistance welded titanium alloy articles in a vacuum or inert environment at temperatures in a range of 1675.degree. F. to 1825.degree. F. for a period of 15 minutes to 4 hours. The process of the present invention is particularly useful in providing efficient joining of face sheets to a honecomb core element.

Abstract: A housing provides temperature monitoring and temperature control of a specimen, while the specimen is being exposed to plasma environments for in-situ reactivity studies or other plasma processing purposes. The housing is adaptable for use with a temperature controller and a pressure measurement device. The housing includes a temperature monitoring mechanism and temperature control connections. The temperature monitoring mechanism provides in-situ specimen temperature indications. It includes a first enclosure having a specimen supporting portion on an exterior surface thereof. A fluid conduit has a first end in fluid communication with an interior portion of the first closure. A second enclosure has an interior portion thereof in fluid communication with a second end of the fluid conduit. The second enclosure includes the ability for attachment to a pressure measurement device.

Abstract: A first-order filter apparatus 48 (FIG. 4) includes an integrate-and-dump (I&D) circuit 50 and an output loop 52. The I&D circuit 50 is driven by a cyclic scaling element 54, which multiplies N consecutive input signals 56, x(m+1) to x(m+N), by a cycle of N scaling factors 58, c(1) to c(N). The I&D summer 60 drives a double-throw switch 62. The double-throw switch 62 applies the output of the I&D summer 60 to an I&D delay element 64 for N-1 input clock cycles, and for an Nth input clock cycle to the input of a non-cyclic scaling element 66. The non-cyclic scaling element 66 scales its input by a non-cyclic scaling factor, and applies its output to one input of a feedback summer 68. The output of the feedback summer 68 is y(k), the output of the apparatus. The index k advances by one every time that the index m advances by N. The output of the feedback summer 68 is also applied to an output feedback multiplying element 70, which multiplies it by B.sup.N.

Abstract: This invention relates to fiber optic networks for the two way communication of light signals. One optic fiber may carry bidirectional signals to many nodes connected to the optic fiber by bidirectional passive optic couplers. Passive unidirectional to bidirectional passive optic couplers can bridge between bidirectional optic fiber networks and unidirectional fiber optic networks. Thus optical signals can be transported to and from each node to all other nodes such that each node is in contact with all the other nodes on the network.

Abstract: A method and apparatus for moving a first carrier tape in a first direction along a path, and a second tape toward the first tape, both in an incremental manner. After each increment of movement of the first tape, the second tape is advanced a proportional increment into overlying contact with the first tape. A press squeezes the first and second tape layers together, and a cutting mechanism is actuated to sever the overlying segment of second tape. The incremental movements of the first and second tapes are regulated so that the length of each second tape segment laid on the first tape is equal to the distance of travel of the first tape in the first direction. The direction of movement of the first tape is reversed so that at least one layer of second tape can be applied to the first tape.

Abstract: Planar antennas 10a, 10b require impedance matching with their associated transceivers 20a, 20b. Conventionally, an inductance coil is placed between the transceiver 20a, 20b and the antenna 10. Such coils add loss, require space within the transciever, and increase costs. This invention replaces the inductance coil with a planar transmission line 18a, 18b within the planar antenna 10a, 10b, such as a co-planar line, slotline, or microstrip line. If desired, active circuits 30 may be applied across the transmission line 18a, 18b, with an RF choke 42 being used to allow a dc bias to drive the active circuits 30 while preventing interference with RF operation.

Abstract: The in-phase channel 28 of a complex demodulated resonator data output signal 12 should contain all of the sensed information, and the quadrature-phase channel 32 should contain none of it. This will not happen if the phase of the reference signal 14 is incorrect. The phase may be adjusted by first filtering each demodulated channel with a respective low-pass dc-blocked filter 34, 38 which passes only the frequencies of the sensed information. If the sensed information gets through on both channels, then there will be a non-zero cross-correlation between the channels. This cross-correlation can be servoed to a minimum by use of a feedback signal 22. Doing so will cause all of the sensed information to be in one channel 28, and diagnostic information to be in the other channel 32.

Abstract: An optical coupler for use in fiber optics for splitting light signals into two or more portions wherein the intensity of the light on the outgoing optical fibers can be accurately controlled. The optical coupler consists of a sending GRIN lens and two or more adjacent receiving GRIN lenses wherein a portion of each receiving GRIN lens has been removed and the receiving GRIN lenses are attached along a common border formed by the removed portion of the GRIN lenses.

Abstract: The vehicle includes a fuselage; a plurality of lifting surfaces attached to the fuselage having control devices attached thereto; and, an articulated propulsion system attached to the fuselage. The propulsion system includes a duct assembly pivotally connected to the fuselage. The duct assembly includes a duct and a propeller assembly mounted within the duct. A motor assembly is connected to the propeller assembly. The duct assembly may be positioned in a substantially vertical position to provide sufficient direct vertical thrust for vertical take-off and landing and may be directed in other positions to provide a varying spectrum of take-off and landing configurations, as well as a substantially horizontal position for high speed horizontal flight. Use of the control surface in the ducted propulsion assembly provides VTOL capability in a very small environment. The environment is not required to be prepared in any special manner.

Abstract: The optical coupler includes first, second and third port assemblies and a deflecting element. The first port assembly receives a first optical signal, the first port assembly including a first lensing element. The second port assembly emits a predetermined, transmitted portion of the first optical signal. The second port assembly includes a second lensing element. The deflecting element is positioned between the first and second port assemblies. The third port assembly includes a third lensing element. The deflecting element and the third port assembly are so positioned and arranged such that a deflected portion of the first optical signal is deflected from the deflecting element and directed through the third port assembly. The predetermined, transmitted portion of the first optical signal is directed through the second port assembly without being deflected by the deflecting element.

Abstract: A majority voted multiple-fault tolerant power switch for delivering power from a power source to an intended load. The power switch includes an optical voter, which has a photo conductor array for receiving optical voter input commands from a control system and for selecting a voter output from the majority of the input commands. An electronic power switch receives power input from the power source. The power switch is controlled by the voter output. An output from the power switch is connected to the intended load. A voltage source supplies the voltage to the optical voter. An operational amplifier circuit is connected to the electronic power switch to limit over current and inhibit reverse current in the electronic power switch.

Abstract: An oxidation protection coating for metal substrate surfaces. The coating, according to a preferred embodiment, comprises an initial or first layer of a glass-ceramic, such as a barium aluminosilicate composed chiefly of baria, silica and alumina; or mullite, composed of silica-alumina or, alternatively, baria-silica. Titanium dioxide, nickel oxide or SnO.sub.2 can be added. The next layer of the coating is comprised of alumina or silicon carbide. The third or final layer is comprised of a thin layer of silica or a high-silica material, e.g., a silica containing 4% B.sub.2 O.sub.3. For a thicker third layer, particles of a dark solid, such as boron silicide, ferrous oxide, ferric oxide, nickel oxide, manganese dioxide, carbon or silicon carbide, can be incorporated. The three-layer coating provides high emittance and low catalytic activity for the recombination of oxygen and nitrogen, as well as being a hydrogen diffusion barrier.

Abstract: A compact diffuser for recovering pressure from a supersonic flow with boundary layers. Sharp splicer plates near the wails form boundary layer scoops and separate the flow into an inner coreflow chapel and outer chambers containing small supersonic ejector nobles. The coreflow without boundary layers undergoes a single near-normal shock to recover pressure. The boundary layers are pumped to the recovery pressure in the outer ejector chambers. The subsonic part of the boundary layer flow to the outer chambers can be choked against boundary layer scoop inlet corners to isolate the upstream flow. The leading edge angle of the splicers may be selected to help induce coreflow shocking.

Abstract: Noise may be reduced or eliminated from a digital sawtooth signal representing the phase of a periodic signal. This may be done precisely, even when inexpensive fixed-point arithmetic is used. In one aspect of the invention, the input signal (noise plus true signal) 12 is filtered to produce, in succession: (a) mod one differentiated noise plus slope of true phase signal 28; (b) mod one differentiated noise plus slope of residual phase signal (true phase signal minus estimated slope of true phase signal) 36; (c) mod one differentiated noise 46; (d) estimated noise 62; and (e) smoothed phase signal 72. In a second aspect, a noisy phase signal 12 is extracted from a first arbitrary periodic signal and the above steps are used to generate a noise-reduced phase signal 72. The noise-reduced phase signal 72 is then used to generate a second arbitrary periodic signal of the same frequency.

Abstract: A friction boring process creates a corrosion resistant fine grain microstructure in the wall surfaces of holes bored in aluminum alloy materials. A rotating tool is inserted directly into the aluminum material, or into a pre-drilled pilot hole, at a sufficient rotational velocity and feed rate to cause working that extends beyond the diameter of the tool, frictional heating, and extraction of aluminum material by metal deformation rather than cutting action as with a conventional drill bit. Burring, smoothing, and otherwise removing aluminum material extracted from the hole may be performed by a finishing segment that limits insertion depth of the tool. Frictional heating generates a temperature sufficient for rapid recrystallization of the remaining worked metal to form a fine grain microstructure to a depth of about 2.5 mm in the hole surfaces. Corrosion protection is retained even if some fine grain material is removed during a subsequent reaming operation.

Abstract: A family of cesium-germanium halide salts have utility as nonlinear optical crystals in applications including electro-optics and optical frequency conversion. These salts have the general formula CsGeCl.sub.x Br.sub.y I.sub.z, in which x, y, and z equal 0 through 3, inclusive, and where x+y+z=3. In contrast to well-known oxygen-containing materials, such as LiNbO.sub.3, these cesium-germanium halide salts exhibit optical nonlinearity with an extremely wide transparency range (without significant absorption) at wavelengths from about 0.4 .mu.m to greater than 25 .mu.m (covering the entire MWIR and LWIR regions). Based on Ge.sup.2+ ions, these halides have non-centrosymmetric perovskite structures. The halide ions form a strongly coordinating octahedral environment about the Ge.sup.2+ ions and resist migration in an electric field. The Ge2+ ions, however, are shifted slightly off center in the tetragonal phase, leading to a net electric dipole moment in each unit cell.

Abstract: An apparatus for attenuating traveling wave reflections from a surface, due to an impedance mismatch between the surface and free space. The apparatus includes a resistive element having an impedance between that of the surface and free space. The resistive element is positionable relative to the surface so as to minimize the impedance mismatch between the surface and free space. The resistive element is preferably a resistively graded element, which includes a forward end with an impedance approaching the impedance of the surface. An aft end of the resistively graded element has a high impedance relative to free space. The aft end is positionable sufficiently distant from the surface so as to minimize any traveling wave reflection due to impedance mismatch between the surface and free space.