Abstract: An optical system and method include a short coherence length edge, emitt LED, a fiber optic coupler probe, and a Michelson interferometer to measure the parameter of thickness of optical devices, such as thin silicon substrate samples and to characterize other parameters of optical waveguide devices such as absolute attenuation, effective refractive index, and changes in these parameters with the application of a modulation voltage or an external disturbance. The measurable thickness range from a few to hundreds of microns with a thickness precision exceeding 0.1 micron for a 10 micron sample. In situ localized measurements of samples in an etching chamber are obtainable to control processing and provide for thickness uniformity. Attenuation measurements for optical waveguides compare the values of interferogram maxima at the values of the reference arm path length to changes corresponding to one and two times the optical path length of the sample.

Abstract: A method is provided for forming a multi-cell photovoltaic circuit on an insulating substrate, comprising the steps of: forming a photovoltaic junction between p-type and n-type layers in a silicon wafer; bonding the silicon wafer to an insulating substrate after forming the photovoltaic junction; patterning the silicon wafer to produce isolated photovoltaic cells; and electrically interconnecting the photovoltaic cells.

Abstract: A tunable laser is described in which the gain element is fabricated to produce wavelength dispersion within the laser resonator cavity. Specifically, the laser gain element has Brewster angled entrance and exit faces which allow it to operate as a wavelength dispersive element while simultaneously performing the functions of an optical gain element within a laser cavity. Wavelength tuning is effected by angular rotation of one of the end reflective elements in the cavity. By using suitable dispersive materials for the laser gain element no additional tuning elements are required providing high efficiency, low threshold laser operation for a variety of optical excitation methods. The laser gain element replaces other discrete intracavity laser tuning means required for tunable lasers, including prisms, diffraction gratings, and birefringent filter elements.

Abstract: Radio-wave propagation is rapidly predicted by a hybrid computational method that uses Ray Optics techniques to calculate radio field strength above a limiting radio-wave ray, Parabolic Equation techniques to calculate radio field strength below the limiting radio-wave ray and below a predetermined altitude, and a newly created Extended Optics method to compute radio field strength in an area of the atmosphere below the limiting radio-wave ray and above the predetermined altitude. Rays in the extended optics area are initialized from the elevation angle that rays traced through the parabolic equation area make with the predetermined altitude. Where reflected, direct or origin created rays do not exist within the parabolic equation area, the elevation angle for the ray that does exist at the furthest range (optical limit) is used to initiate ray tracing in the extended optics area for ranges beyond the optical limit.

Abstract: An electronic circuit architecture time-division-multiplexes analog sensor ignals from a distributed sensor array onto a common transmission line in a digitally encoded format. The architecture synchronizes the multiplexing, sampling and encoding to ensure a proper settling of the analog data signals and is fabricated to be compact with low power consumption for a cost-effective implementation for a number of sensors.

Abstract: A high resolution lidar is used to backscatter light from atmospheric aerosols. The actual relative humidity is measured at altitudes corresponding to those from which the backscattered light occurs. A mathematical relationship between the two is then derived and this is used to predict atmospheric relative humidity from subsequent lidar backscatter s measurements. The predicted relative humidity is used with temperature and pressures derived from standard lapse rates to calculate the radio refractivity of the atmosphere. Radio ray coverage is then determined based upon the calculated radio refractivity.

Abstract: A method of producing scintillation phosphor X-ray detector arrays using k materials and repetitive manufacturing techniques. The structures formed by this method may be used to detect x-rays, charged particles and neutral particles by converting the incident radiation into optical radiation. Detectors manufactured by the methods of this invention will produce better x-ray images and reduce the amount of radiation a medical patient or industrial target is subjected to.

Abstract: The invention provides a fiber optic microcable having a uniform cross seonal dimension which may be manufactured in continuous lengths that exceed 10 kilometers. The microcable is comprised of an optical fiber core, a buffer surrounding the core, and a protective sheath surrounding the buffer consisting of an electromagnetic radiation cured resin impregnated with fibers suspended in the resin to enhance the resistance of the microcable to physical damage. The microcable is fabricated by soaking the fibers in an electromagnetic radiation curable resin, placing the wetted fibers around the core and buffer to form a matrix, and then irradiating the matrix with electromagnetic radiation to cure the resin.

Abstract: A light energized high voltage direct current power supply comprises a li source including solid-state laser diodes powered by electrical current at a voltage level, V.sub.1, for generating light; a photocell array positioned to receive the light and fabricated with silicon-on-sapphire for providing electrical power having an output voltage V.sub.2, where V.sub.2 >V.sub.1, where the photocell array includes serially connected photovoltaic cells; and a voltage regulator operably coupled to the light source and the photocell array for controlling the output of the power supply to a predetermined voltage level.

Abstract: The present invention provides an apparatus and method for generating blue laser light having a wavelength corresponding to a solar Fraunhofer line. The blue laser light is at a frequency that has both excellent transmissibility through sea water and a high signal-to-noise ratio. A first laser beam, generated using an injection-locked excimer XeCl laser, is down-converted by a first-Stokes order shift of 2.times.4155 cm.sup.-1 in a first Raman cell containing H.sub.2 gas at a pressure of about 10 atmospheres. The output of the first Raman cell is down-converted by a first Stokes shift of 3628 cm.sup.-1 in a second Raman cell containing HD at a pressure of about 10 atmospheres so that the output of the second Raman cell has a wavelength of 486.366 nm. This wavelength corresponds to the FE I solar Fraunhofer line.

Abstract: An uninterrupted event-time recorder enables high-precision measurements of the time-of-occurrence of randomly- and rapidly-occurring, digitally specified events such as the leading and/or trailing edges of asynchronous pulses. The lowest order binary digits of the recorder are constructed of high-speed synchronous integrated circuit counter devices. For an N-bit timer having M low-order bits, the highest order (N-M) bit counting is executed by two parallel (N-M)-bit slow-speed counters, one of which is incremented by the terminal count of the M-bit high-speed counter and the other which is incremented by the most significant bit (MSb) of the M-bit counter. The (N-M)-bit counters are read out through a multiplexer controlled by the MSb.

Abstract: A ceramic material for electronic circuit devices is sintered at less than r equal to 1000.degree. C. temperature. A filler material such as quartz and a glassy binder RO-Al.sub.2 O.sub.3 -B.sub.2 O.sub.3 are mixed together along with an appropriate glassy binder prior to firing. RO is drawn from the group of metal oxides MgO, CaO, SrO, BaO, ZnO or CdO and the glassy binders form no more than 40 vol % of the ceramic material. The glassy binder has a suitable viscosity and other properties so that after it is mixed with the quartz filler, sintering occurs at the relatively low temperature. As a consequence, high conductivity conductors made of copper, silver and gold can be appropriately metallized prior to firing. The strength and low dielectric constant of the ceramic material make the material well adapted for ceramic substrates, thick films and the like which are used in VHSIC and VLSI applications.

Abstract: A meteor burst communication network is disclosed that consists of a plurality of meteor burst communication stations that relay radio messages off of meteor burst trails from one station to another. Each station includes an antenna operably coupled to a receiver and transmitter, a display, a message input device, a computer operably connected to the aforementioned equipment, and a clock that provides a time base to the computer. The computer provides instructions to the transmitter and outputs to a display. The program determines if a message has been received by the receiver. If a message has been received, it is stored in the computer memory. The computer then instructs the transmitter to transmit a probing message for a predetermined period of time.

Abstract: A technique and apparatus employs a plurality of laser pumping emissions fed as collimated parallel beams from a multi-faceted reflective solid with highly reflective faces into a single aperture lens to concentrate all the laser pumping emissions onto a spot on the face of the laser crystal for the responsive longitudinal pumping thereof.

Abstract: An acoustic source apparatus has a loudspeaker enclosed within a substantly pressure resistant and water tight enclosure. Acoustic energy from the loudspeaker emanates through an opening in the enclosure. This opening is covered by a resilient diaphragm that transmits the acoustic energy to an aqueous medium. A net constrains the diaphragm to a preselected size and shape. The net further impedes overexpansion of the diaphragm and restrains the diaphragm from migrating due to buoyancy. Additonally, the net stiffens and strengthens the diaphragm, to thereby increase the resonant frequency, impedance and quality factor of the transducer system and decrease the transmission bandwidth of the system. Constraining the transducer diaphragm with the net makes higher transducer source levels possible.

Abstract: A flux containment device entraps an unneeded portion of the radiated ene emitted by a reference source lamp so that a determinable amount of radiation is projected to electro-optical sensors for calibration purposes. A double-walled, concentric can-shaped enclosure, provided with a nonreflective coating on its inside surfaces, has an aligned calibration optical axis aperture for projecting the determinable amount of radiation and a diametrically opposed light trap opening to accommodate a light trap that eliminates unwanted reflections. The double walls are held apart by nonconductive spacers to avoid unwanted heat transfer. A fan forces cooling air through an appropriately located vent hole in the can-shaped enclosure to avoid direct impingement on the lamp.

Abstract: A ceramic material for electronic circuit devices is sintered at less than or equal to 1000.degree. C. temperature. A filler material such as quartz and a glassy binder RO--Al.sub.2 O.sub.3 --B.sub.2 O.sub.3 are mixed together along with an appropriate glassy binder prior to firing. RO is drawn from the group of metal oxides MgO, CaO, SrO, BaO, ZnO or CdO and the glassy binders form no more than 40 vol% of the ceramic material. The glassy binder has a suitable viscosity and other properties so that after it is mixed with the quartz filler, sintering occurs at the relatively low temperature. As a consequence, high conductivity conductors made of copper, silver and gold can be appropriately metallized prior to firing. The strength and low dielectric constant of the ceramic material make the material well adapted for ceramic substrates, thick films and the like which are used in VHSIC and VLSI applications.

Abstract: The present invention provides an apparatus for launching and recovering a submersible vessel from a ship, and includes a gantry that pivots in an arc extending over and beyond the aft deck of the ship. A lift line passes about a head sheave that pivots from the top of the gantry and threads through a saddle that also pivots from the top of the gantry. The saddle is clamped to the vessel. The lift line is connected to the top of the submersible vessel and passes about a ram tensioner which may be mounted on the deck. After a winch pays out the lift line to lower the vessel into the ocean, the saddle is disconnected from the vessel and the lift line is rethreaded back out of the saddle. A tether provides a communicative link between the ship and the vessel, and may pass about a hanging sheave suspended from the gantry when the vessel is in the ocean. Recovery of the vessel is the reverse of deployment.

Abstract: A method and apparatus for presenting elevation angle information with rect to overhanging objects to an operator of a submersible incorporates a substantial portion of the sonar equipment found onboard conventional submersibles. Reflections of radiant energy from the objects are received by a highly directional array of hydrophones. The received reflections are time varying gain attenuated to substantially compensate for range-dependent signal variations such as are due to changes in scattering areas, spreading loss and attenuation loss. Using time varying gain processing and by taking into account the known directivity pattern of the hydrophones, the received reflections are reduced to represent signal characteristics due substantially to the elevation angle of the incoming reflections. These modulated reflections are quantized by first sorting the reflections into bands according to amplitude intensity and then by assigning a distinct color to the individual bands.

Abstract: A synthesizer for complex acoustic signatures includes a generator for an ectrical analog of a complex acoustic waveform corresponding the the "shaft rub" noise produced by the interaction of a marine propeller shaft and a stern tube or other through-the-hull marine fitting. This circuitry employs digital random generators to produce a nonrecurring characteristic signal synthesizing this acoustic noise. An arrangement to process this signal with other simulation circuitry is also disclosed.