Abstract: A high-Q pump cavity is formed from undoped crystal pieces that are diffusion bonded to a doped core of the same crystal host material. The resulting monolithic pump cavity has 2 opposing convex-curved sides which have a highly-reflective coating on their outer surfaces, except in narrow slit-shaped areas on each curved side through which laser-diode-supplied pump light enters the cavity. The curvature of the two curved sides is such that nearly all the pump light rays that pass through the slit-shaped areas are focussed by the curvature onto the doped core, and rays that enter the cavity are redirected through the doped core many times, resulting in efficient, uniform absorption. The cavity has two opposing flat sides that interface with metal heat sink blocks to facilitate the removal of internally-generated heat. Thermally induced astigmatic lensing caused by this heat is countered by cavity design in which the core shape and the dimensions of the cavity minimize this astigmatism.

Abstract: A multiple elastic feature network having N independent sets of M feature specific neurons that respond to the temporal properties of a number of targets. The targets are represented by sets of M feature specific coordinates. Each of the neurons and its coordinates are labeled with a different one of the feature types, and have an associated receptive field and distortion, locking and expectation parameters. A sequence of candidate coordinates, which include the targets' coordinates as well as false or ghost coordinates, is input to the MEFN. Each successive candidate coordinate selects the closest neuron that has the same feature type and whose receptive field includes the candidate coordinates. The coordinates of the selected neuron and the other neurons in its set are adjusted towards the candidate coordinates.

Abstract: A microwave/millimeter wave circuit structure supports discrete circuit elements by flip-chip mounting to an interconnection network on a low cost non-ceramic and non-semiconductor dielectric substrate, preferably Duroid. The necessary precise alignment of the circuit elements with contact pads on the substrate network required for the high operating frequencies is facilitated by oxidizing the interconnection network, but providing the contact pads from a non-oxidizable material to establish a preferential solder bump wetting for the pads. Alternately, the contact bumps on the flip-chips can be precisely positioned through corresponding openings in a passivation layer over the interconnection network. For thin circuit substrates that are too soft for successful flip-chip mounting, stiffening substrates are laminated to the circuit substrates.

Abstract: Continuous, elongated nickel plated graphite fibers are bound with an epoxy and are formed into a structural shape (11). An area (13) of the epoxy is removed by bead blasting to expose a layer of the plated graphite fibers (14), which are aligned in the desired direction of radio frequency current propagation. The bead blasted area (13) is then silver plated to obtain good contact to the plated graphite fibers (14) and resultant high conductivity from the structural shape (11).

Abstract: A space module has a base and one or more side walls attached to the base. A top panel is attached to the one or more side walls so that the base, the one or more side walls and the top panel enclose an interior volume of space which is physically divided into a first area and a second area which are thermally and structurally segregated from one another.

Abstract: A novel, inexpensive sensor and method for detecting volatile compounds in the gas phase at concentrations of less than about 500 ppm in ambient air are provided. The sensor comprises (a) a dielectric substrate having a major surface; (b) a pair of electrically conductive electrodes disposed on the major surface of the substrate; and (c) a conductive polymer covering the pair of electrically conductive electrodes, with the conductive polymer doped with appropriate dopants in measurable excess of that stoichiometrically required to change the conductive polymer from a neutral state to a charged state to provide requisite conductivity. A method for making the sensor is provided, as is a method of use of the sensor which relates to its use in a monitoring system comprising a means for measuring the conductivity of the sensor connected to a warning means for providing an indication when the conductivity reaches a predetermined level.

Abstract: Various structures for cantilever beam tunneling rate gyro devices formed on a single substrate are disclosed. A cantilever electrode having a plurality of portions extending from the substrate with one end of the cantilever is suspended above the substrate at a distance from a tunneling electrode so that a tunneling current flows through the cantilever and tunneling electrode in response to an applied bias voltage. The cantilever and tunneling electrodes form a circuit that produces an output signal. A force applied to the sensor urges the cantilever electrode to deflect relative to the tunneling electrode to modulate the output signal. The output signal is a control voltage that is applied between the cantilever electrode and a control electrode to maintain a constant tunneling current. In the preferred embodiment, two cantilever portions extend from the wafer surface forming a Y-shape. In a further embodiment, a strap is fabricated on the cantilever electrode.

Abstract: A phased array radar system employs programmable microelectromechanical (MEM) switches and transmission lines to provide true time delays or phase shifts in order to steer the array beam. The array includes an excitation signal source, a power division network for dividing the excitation signal into a plurality of excitation signal components, a plurality of programmable time delay/phase shift circuits including the transmission lines and MEM switches, and a plurality of radiating elements. An adaptive controller provides the control signals to set the MEM switches and select the time delay/phase shift through each time delay/phase shift circuit, thereby steering the array beam to a desired direction.

Abstract: A Clock and Bias Module (CBM 10) includes a low pass filter speed-up switch (U104, U114) to provide both a long time constant and fast settling; bootstrapped power supplies (VR101-104) to provide a wide, programmable output voltage range with overload protection; an integrating output driver (20) to provide controlled clock slew rates while maintaining a precision rail voltage; an active current steering bridge (Q5, Q6, CR1, CR2) to allow computer programmable control of slew rates; a current measurement circuit (U14, U15, U19) that enables sensing an average load current in the presence of large voltage swings; and a compact modular implementation that allows for close proximity of the circuitry to a unit under test. The CBM provides IR Detector FPA electrical stimulus in an automated testing environment. The clock generation circuitry is fully programmable for rail voltage, rising slew rate, and falling slew rate.

Abstract: A grazing incidence optic is fabricated by grinding, polishing, or both, using a tapered, barrel-shaped tool. The optic surface to be ground or polished is placed in contact with a selected portion of the grinding or polishing surface of the tool, and the tool is rotated about its longitudinal axis. The optic is subjected to a reciprocating grinding movement along the length of the barrel tool. A helical groove in the tool allows slurry to pass between the optic surface being worked and the tool surface. Air is forced between the optic surface and the tool surface to release the optic from the tool.

Abstract: A microelectronic device includes a substrate device and a dark mirror coating overlying one side of the substrate device. The dark mirror coating has a via therethrough to the substrate device. The dark mirror coating has a plurality of alternating layers of dielectrics and metals. Each metallic layer has an electrically nonconducting region adjacent to the vias, preferably formed by anodizing the metallic layers after deposition.

Abstract: Epitaxial growth of a chirped superlattice with constant dopings is achieved with minimal growth interruption time. This is done by doping only one of the two compositions during growth of its layer. For example, in the growth of a plurality of alternating layers of InP and GaInAs to form the superlattice, either the InP layers are doped with an n-type dopant, such as silicon, or the GaInAs layers are doped with a p-type dopant, such as beryllium. Alternatively, InP can equally be doped p-type (with beryllium) and GaInAs can be doped n-type (with silicon). In either case, the doping scheme described herein is easily done during molecular beam epitaxial growth by opening and closing the shutter of the dopant (silicon or beryllium) source cell at the appropriate times. To the electrical carriers, the doping superlattice scheme of the present invention presents a uniform doping without any need to change the doping cell temperature.

Abstract: A gold-coated molybdenum article (30) is made by furnishing a substrate (32) made of pure molybdenum or an alloy of molybdenum, and preparing a slurry of gold powder, acrylic binder, and acetone liquid carrier. The slurry is applied to a portion of a surface of the substrate. The substrate with applied slurry is heated in vacuum or inert atmosphere to an elevated temperature, preferably about 2040.degree. F., and thereafter cooled to ambient temperature. The result is an article (30) having at least a portion of the substrate (32) covered with an adherent gold coating (34).

Abstract: A measurement optical fiber is placed into contact with a geological structure, and a reference optical fiber of about the same length is not contacted to the geological structure. An input beam of light is transmitted down the lengths of the measurement and reference optical fibers, and the interference fringes formed between the reflected beams in the two optical fibers are counted to determine the geological displacement, and thence the geologic strain, experienced by the measurement optical fiber. Preferably, multiple pairs of the measurement and reference optical fibers are used, the optical fibers of the various pairs being of different lengths. The difference in displacement measured by any two pairs is a measure of the geological strain in the region between the ends of the two pairs. The multiple pairs are conveniently provided in two optical fiber cables, a measurement cable which contacts the geological structure and a reference cable which extends parallel and adjacent to the measurement cable.

Abstract: An intensity modulator having a Mach-Zehnder structure with first and second waveguide arms formed of an electro-optic polymer. The active molecules of the waveguide arms are poled in first and second different and substantially orthogonal directions. Electrodes are arranged to receive a modulating voltage and generate first and second electric fields which are respectively aligned with the first and second directions. As a consequence, the modulation depth of an optical signal which is transmitted through the modulator is substantially insensitive to the polarization of the signal. Other embodiments combine mode splitters and combiners with first and second Mach-Zehnder modulators which have electro-optic polymer waveguides. The active molecules of the arms of the two Mach-Zehnder modulators are poled in orthogonal directions.

Abstract: A catadioptric one-to-one optical relay system which is telecentric in both object and image space. The system includes three modules, which include a spherical primary mirror, a spherical secondary mirror with a zero power doublet for axial color correction, and an X-prism for spectral division. The chromatic aberration generated by the X-prism is compensated by the zero power doublet corrector. Because the system is telecentric in both object and image space, the coatings associated with the X-prism are simplified. The system can be used in telescopes, optical systems with sensor protection, and color CCD assemblies.

Abstract: Frequency multiplexers that incorporate either a power divider network or a power coupling cavity in conjunction with photonic bandgap filters. The frequency multiplexers comprise a signal input and a plurality of signal outputs. In a first embodiment of the multiplexer, a 1-to-N power divider network is coupled to the signal input, and a predetermined number of photonic bandgap filters are coupled between the divider network and the plurality of signal outputs and that are driven by the divider network. Each photonic bandgap filter has an predetermined bandpass characteristic such that the plurality of filters cover the total input signal bandwidth. In a second embodiment of the multiplexer, a cavity is formed between the signal input and the plurality of filters. The spatial locations of the filters tailor the propagation properties of the cavity so that a corresponding plurality of propagating modes are established linking the different input frequency bands and the signal output.

Abstract: A method for fabricating resilient z-axis contacts to electrically interconnect IC wafers or MCMs in 3-D integrated circuits uses photolithography to provide larger carrier sizes, higher contact densities by decreasing the spacing, smaller contact footpads, and precise control of the contact's shape and position. The contacts are fabricated by forming photoresist patterns on the carrier's top and bottom surfaces that are initially rectangular, and then reflowing the photoresist materials to provide smooth surfaces suitable for forming the metal contacts, and depositing metal layers over the respective patterns. Second photoresist patterns are formed over respective metal layers to conform with the contact's shape, the metal is etched away according to the pattern, and the photoresists are removed such that the remaining metalization forms a resilient z-axis contact that is attached to the carrier and extends therefrom with a predetermined shape.

Abstract: An epitaxial structure and method of manufacture for a infrared detector device with low dislocation density, especially for high performance large area focal plane arrays. Preferably, the epitaxial structure includes a buffer layer comprising a Hg-based II-VI material and an overlayer comprising a detector comprising a Hg-based II-VI material. The buffer layer is transparent at the operating frequencies of the detector.

Abstract: A method is provided for preparing the surface of a cyanate ester polymer or composite for metal plating. The surface is treated with a preheated solution containing a compound selected from the group consisting of at least one quaternary ammonium hydroxide and at least one primary amine. The method of the invention operates to improve adhesion between the treated surface and a subsequently plated metal, such that the resulting cyanate ester polymer or composite may replace certain metallic components in such applications as aircraft, spacecraft, and automobiles given its highly conductive metallic coating.