Abstract: A method is provided for fusion-splicing with a laser beam two optical components, one of the optical components (e.g., an optical element such as a lens) having a surface that has a comparatively larger cross-sectional area than a surface of the other optical component (e.g., an optical fiber).

Abstract: A missile seeker. The inventive missile seeker includes a dome within which a novel optical arrangement is retained. The optical arrangement includes a first prism mounted for rotation about an optical axis and a second prism mounted for rotation about the optical axis. In the illustrative embodiment, the first and second prisms are Risley prisms. In addition, the illustrative implementation includes a first motor arrangement for rotating the first prism about the optical axis and a second motor arrangement for rotating the second prism about the optical axis. A controller is provided for activating the first and second motors to steer the beam at an angle &phgr; and nod the beam at an angle &thgr;. In a specific implementation, the first prism and/or the second prism have at least two surfaces contoured to correct for optical aberration. A teaching is provided to contour the surfaces to correct for astigmatism, coma, trefoil and other non-rotationally symettric abberation.

Abstract: Switching apparatus for switching on and off one or more microwave tubes. A preferred embodiment of the switching apparatus comprises a solid state magnetron switcher that switches a plurality of magnetrons on and off using a plurality of high voltage (IGBT) switches. The microwave tubes or magnetrons are driven from a single power supply. The technical approach employed in the present invention places all microwave tubes or magnetrons into low level oscillation prior to switching them into full conduction. This maintains minimal voltage across the high voltage switches while allowing only a small percentage (1-2%) of full load current to be drawn.

Abstract: A sandwich device was prepared by electrodeposition of an insoluble layer of oligomerized tris(4-(2-thienyl)phenyl)amine onto conducting indium-tin oxide coated glass, spin coating the stacked platinum compound, tetrakis(p-decylphenylisocyano)platinum tetranitroplatinate, from toluene onto the oligomer layer, and then coating the platinum complex with aluminum by vapor deposition. This device showed rectification of current and gave electroluminescence. The electroluminescence spectrum (&mgr;max=545 nm) corresponded to the photoluminescence spectrum of the platinum complex. Exposure of the device to acetone vapor caused the electroemission to shift to 575 nm. Exposure to toluene vapor caused a return to the original spectrum. These results demonstrate a new type of sensor that reports the arrival of organic vapors with an electroluminescent signal.

Abstract: A bistatic passive radar system having a display; a first directional antenna for determining the angle between the reference azimuth of the bistatic passive radar system and the line of sight to a host transmitter; an omnidirectional antenna for receiving reflected radar pulses from targets at any bearing; and a second directional antenna for determining the angle B between the line of sight to the host transmitter and a second line which extends from the bistatic passive radar system to a selected target. The angle of the second directional antenna is indicated by a B cursor on the display. The system includes a bistatic range correction circuit that utilizes an empirical determination of the distance D between the bistatic passive radar system and the host transmitter for determining the correct range for display of a selected target.

Abstract: An image processing system and method. In accordance with the inventive method, adapted for use in an illustrative image processing application, a first composite input signal is provided based on plurality of data values output from a sensor in response to a scene including a target and clutter. The composite signal is processed to provide a plurality of tap weights. The tap weights are generated by the matrix of data values which is first filtered by a wavelet transform to provide a set of coefficients. The coefficients are sparsened to provide a sparse matrix. The sparse matrix is then inverse wavelet transformed to provide the tap weights. Finally, the tap weights are applied to the composite signal to yield a clutter reduced output signal. In the illustrative implementation, the matrix is a covariance matrix. However, a method for implementing the teachings of the invention in the data domain is also disclosed.

Abstract: A device for manipulation of acoustic waves is provided, comprising a functionally-graded material for interposing between a source of the acoustic waves and a target, which may be a detector of manipulated acoustic waves. The functionally-graded material has a gradient in acoustic wave velocity which is obtained by the generation of a gradient in at least one of the following properties: elastic modulus, Poisson's ratio, and density, that is perpendicular to a direction of propagation of the acoustic waves. The gradient is axial. Biaxial acoustic velocity gradients may be used for focusing/waveguiding (high-low-high) or dispersing (low-high-low), while monoaxial acoustic velocity gradients may be used for wave steering. Also in accordance with the present invention, a method of making the device is provided, comprising: (a) providing the source of acoustic waves; (b) providing the target for acoustic waves, e.g.

Abstract: A multi-element read-write magnetic recording head for recording information on a magnetic tape and for reading recorded information therefrom is provided. The recording head comprises an equal number of associated read elements and write elements to form a two-gap recording head comprising pairs of read and write elements. The two-gap recording head further comprises a first module and a second module, the first and second modules each comprising a plurality of read and write head elements. A first group of read and write heads is configured to perform in a forward direction of movement of the magnetic tape and a second group of read and write heads is configured to perform in a reverse direction of movement of the magnetic tape.

Abstract: A gas cell is provided for detection of trace gases via intracavity laser spectroscopy. The gas cell comprises a gas cell body having a long body axis, an interior hollow portion along the long body axis, and two end portions, each end portion having two opposed surfaces, one surface of each the end portion cut to an angle with respect to the long body axis and including a laser-transparent window on each face defining ends of the interior hollow portion. The angle is dependent on operating wavelength of the spectrometer and refractive index of the window material at the operating wavelength. Each end portion is provided with a gas line connection in the proximity of the opposed surface, one gas line for introducing a sample gas into the interior hollow portion and the other gas line for exhausting the sample gas from the interior portion. Further, a gas cell holder is provided for supporting and positioning the gas cell.

Abstract: A holographic planar concentrator (HPC) for collecting and concentrating optical radiation is provided. The holographic planar concentrator comprises a planar highly transparent plate and at least one multiplexed holographic optical film mounted on a surface thereof. The multiplexed holographic optical film has recorded therein a plurality of diffractive structures having one or more regions which are angularly and spectrally multiplexed. Two or more of the regions may be configured to provide spatial multiplexing. The HPC is fabricated by: (a) recording the plurality of diffractive structures in the multiplexed holographic optical film employing angular, spectral, and, optionally, spatial multiplexing techniques; and (b) mounting the multiplexed holographic optical film on one surface of the highly transparent plate. The recording of the plurality of diffractive structures is tailored to the intended orientation of the holographic planar concentrator to solar energy.

Abstract: A fiber optics switch has a retro-reflector mirror assembly which reflects a light beam received from an input fiber in an anti-parallel, displaced manner, into one of a plurality of output fibers. Insensitivity to temperature changes, wear and tear, and vibration is achieved as well as very compact size and high speed.

Abstract: A powder coating method includes applying an antistatic material to the surface of an electrically nonconducting substrate. The antistatic material is preferably a fatty amine salt and is applied by spraying. A flow of electrostatically charged powder particles is directed toward the substrate to form a powder coating on the substrate, and the powder coating is thereafter cured.

Abstract: An optically tuned magnetron oscillator employs materials whose electrodynamic properties are altered by the absorption of light. A probe constructed from a leaky dielectric light guide coated with a photoconductive material is inserted into each of the magnetron's cavities. When light is injected into the light guide, it leaks into the coating where it is absorbed, creating free charge carriers whose presence alters the dielectric properties of the material, thereby perturbing the resonant frequency of the cavity. The frequency can be controlled by varying the amount of light injected into each of the optical probes. When no light is present, the resonant frequency of the magnetron cavity will be at one extreme of its operating band; when the light is at full intensity, the change in the properties of the probe will be maximum as will be the change in the resonant frequency.

Abstract: A solar concentrator is provided that comprises two stages. The first stage comprises either a trough-shaped concentrator cusp unit having two major opposed sides joined by two ends. The inner surfaces of the first stage concentrator are mirrored. Further, the ends have two flat, angled surfaces, while the two sides have a Bezier-generated cylindrical shape that approximate parabolic surfaces followed by a straight section. The second stage comprises a bi-axial gradient refractive index (GRIN) element, in which two gradient refractive index materials, each having a high index surface and a low index surface, are joined together along their high index surfaces. The two ends of the bi-axial element are flat, while the two sides also have a Bezier-generated cylindrical shape that approximate parabolic surfaces followed by a straight section. The top surface of the bi-axial element is provided with a cylindrical surface, while the bottom, or exit, surface is ground flat.

Abstract: A system and method adapted for use with a focal plane array of electromagnetic energy detectors to receive first and second frames of image data from electromagnetic energy received from at least a portion of a scene. The first frame is a focused frame and the second frame is an unfocused frame. In a feed-forward path the system compares the first frame to the second frame and provides an error signal in response thereto. In a main path, the system multiplies at least a portion of the second frame of image data with the error signal to provide an noise error corrected output signal. In the preferred embodiment, the error signal is scaled prior to being multiplied by the second frame. An anti-mean (high pass) filter is provided to remove dome shading effects from the frames of image data. In the best mode, the anti-mean filter is disposed in the main path and blurred and focused outputs therefrom are weighted, averaged and stored.

Abstract: A missile has a body with a substantially circular nose opening therein, and a ceramic radome sized to cover the nose opening. A compliant metallic circular transition element is disposed structurally between the radome and the body. The transition element includes an elongated compliant arm region and an upper crossbar region positioned adjacent to the radome such that the lower margin surface of the radome is adjacent to an upper side of the crossbar region. A brazed butt joint is formed between the lower margin surface of the radome and the upper side of the crossbar region of the transition element. A second brazed butt joint is formed between the vehicle body and the lower side of a lower crossbar region joined to the arm region. The brazed joints are formed with a single active braze alloy which permits the entire joining operation to be accomplished in a single furnace cycle.

Abstract: A blackbody radiation source includes an insulated enclosure having a viewing aperture defining a line of sight through the wall of the enclosure. A heat sink, preferably a pool of liquid nitrogen, is located within the insulated enclosure. There is a viewing surface in thermal contact with the heat sink but having an unobstructed view through the viewing aperture. The viewing surface is inclined to the line of sight through the viewing aperture. A sensor is calibrated by placing the sensor in facing relation to the aperture and measuring an output black body signal of the sensor. The viewing surface may be radiatively heated concurrently with the measuring to produce a higher equivalent radiometric temperature.

Abstract: Ashing of an organic film from a substrate is carried out by providing a plasma comprising a gas or gas mixture selected from the following groups: (a) sulfur trioxide alone; (2) sulfur trioxide plus one supplemental gas; and (3) sulfur trioxide plus at least two supplemental gases. Any of the following gases may be employed as the supplemental gas: oxygen, ozone, hydrogen, nitrogen, nitrogen oxides, helium, argon, or neon. Also, a process is provided for forming a plasma in a reaction chamber from reactant gases containing sulfur trioxide. The process includes introducing the sulfur trioxide into the reaction chamber from a storage vessel through a delivery manifold by independently heating the storage vessel and the delivery manifold to a temperature sufficient to maintain the sulfur trioxide in its gaseous state or liquid state and by heating the reaction chamber to control the reaction rate of the sulfur trioxide and also control condensation of the sulfur trioxide to maintain a stable plasma state.

Abstract: A radar processing system is disclosed with an improved cluster target resolution capability. The invention provides a system and method for processing radar returns and generating first and second contiguous range/doppler cells. Within the cells, first and second dichotomous angle measurements corresponding to radar returns in the first and second contiguous range/doppler cells are derived. An adaptive threshold is then applied to the angle measurements to determine whether the first and second measurements correspond to first and second targets in the first and second range/doppler cells respectively.

Abstract: A hybrid film, comprising a first polymer film having a plasma-treated surface and a second polymer film having first and second surfaces, with the first surface of the second polymer film being disposed along the first plasma-treated surface of the first polymer film, has superior thermal and mechanical properties that improve performance in a number of applications, including food packaging, thin film metallized and foil capacitors, metal evaporated magnetic tapes, flexible electrical cables, and decorative and optically variable films. One or more metal layers may be deposited on either the plasma-treated surface of the substrate and/or the radiation-cured acrylate polymer A ceramic layer may be deposited on the radiation-cured acrylate polymer to provide an oxygen and moisture barrier film. The hybrid film is produced using a high speed, vacuum polymer deposition process that is capable of forming thin, uniform, high temperature, cross-liked acrylate polymers on specific thermoplastic or thermoset films.