Abstract: Differential phase measurement techniques and apparatus for accurately loing unknown transmitters over great distances at radio frequencies below HF. A network of separated, time- and phase-synchronized, pairs of receiving stations having vertical whip antennas and having a known base-line geometry with respect to each other are used to accurately measure VLF phase differentials. The measured phase differences are compared against theoretical calculated values to provide highly accurate transmitter location information.

Abstract: A beam switching processor operable to detect a microwave amplitude distrtion associated with an array of receiving antenna ports and to close a single-pole, multiple-throw microwave switch to that port in a matched array of transmit antenna ports which corresponds to the receiving antenna port having the maximum signal amplitude. The receive antenna signals are log amplified and subsequently processed in a logic section which indentifies the input port having the highest energy level and energizes the corresponding microstrip switch-driver circuit.

Abstract: A data analysis system accepts time related data samples which are develo from sets of common wavefronts incident upon a plurality of sensors. The data samples are converted from analog-to-digital form and the Fourier transforms relative to the frequency components are generated. The frequency components of the Fourier transforms are in turn cross-correlated for developing matrices of all possible correlations for each frequency component and then the matrices are integrated over a determinable time period. The resultant integrated matrices are compared with signals representative of an incident plane wave power as a function of its angles of arrival at a sensor array and of its frequency, producing output signals of relative strength indicative of the direction of the origin of the data samples.

Abstract: A pulsed laser produces emitted laser energy by electron impact dissociation of metal dihalide and cyclic recombination. A metal dihalide selected from sub group II-B of the periodic table of elements is contained within an elongate sealed enclosure. Two elongate electrodes having external terminals are supported in parallel relationship within the enclosure, forming a gap parallel to the principal axis of the enclosure. A source of pulsed electric power is connected to the terminals of the two electrodes, producing repetitive transverse electric discharges across the gap. An inert buffer gas is included within the enclosure for aiding electric discharge uniformity, and to provide vibrational relaxation of the lasing medium in its electronic states.

Abstract: An optical beam steering system is provided by a reflective surface mounted n a baseplate which is electromagnetically driven by applied signals to control its angular disposition to a degree of accuracy within fractions of a microradian. Resilient means such as coil springs are attached in pairs to the baseplate to define two orthogonally related axes of movement intersecting at the geometric center of the baseplate. A pivotal support (preferably a jewel bearing) is positioned at the geometric center of the baseplate; first and second pairs of permanent magnets extend from thebaseplate at opposite equidistant points from the pivotal support to define first and second axes of movement which are also orthogonally related.

Abstract: An optical coupler transfers light energy signals relative to an optical h which includes a fiber optic cable. A body member includes first and second ports at opposite ends for supporting first and second terminals of the fiber optic cable in laterally offset alignment relative to each other. First and second reflective elements, preferably of concave spherical configuration, are supported within the body member for collecting and reflecting light energy transmitted through the first and second terminals of the fiber optic cable. The first and second reflective elements are so configured and positioned as to transmit collimated light energy between them for completing the optical path between the first and second terminals of the fiber optic cable.

Abstract: A hand-held, manually operative tool is designed for severing single filat, fiber optic cable. The exertion of a squeeze-like pressure on the handles of the tool cause the fiber optic cable to be gripped firmly and positioned on an anvil member where it may be scored by a sharpened hard element such as a diamond point, for example, at a selectively determined point along the axis of the fiber optic cable. Further actuation of the tool causes the gripping members to be pivoted away from each other thus parting the fiber optic cable at the selectively determined point. The coacting members of the tool are spring loaded for return to their normal unactuated state and the anvil member is preferably a curved surface so as to retain the fiber optic cable in a desired disposition during the scoring operation.

Abstract: Light energy data is generated in sequential interlaced field raster format y a sensor driven in azimuth to detect a panoramic scene. The light energy data is sequentially recorded together with an azimuth rate signal which is a function of the rate that the sensor is driven in azimuth. Because the sensor has been driven in azimuth, however, there is a delay in the sequential detection between first and second interlaced fields of any selected frame of the panoramic scene; consequently, when it is desired to retrieve and playback a "stop-action" image comprised of a selected frame, compensation must be made for the delay. The recorded azimuth rate signal is used to develop a commensurate delay between the two sequential first and second interlaced fields of light energy data comprising the selected frame of light energy data which is desired to playback in "stop-action" form.

Abstract: A device for detecting optical energy signals in an optical path is provi by combining a layer of photoemissive material overlying the optical path and a grounded first electrode positioned in electrical contact with the layer of photoemissive material; a second electrode is positioned in spaced, preferably parallel relationship from the first grounded electrode and a source of dc potential is connected across the electrodes. Upon the transmission of optical energy signals along the optical path, commensurate electrical signals are produced across a load resistance which is connected between the second electrode and the high potential side of the dc potential source. Alternatively the concept may be embodied in a photomultiplier responsive to signals in an optical path. In this embodiment a plurality of dynodes are positioned between the first and second electrodes, spaced at gradually increased distances from the layer of photoemissive material.

Abstract: An improved optical element is provided by an arrangement of optical wavedes disposed with two photoconductive paths and a plurality of electrodes arranged to impress an electric field across the optical waveguide configuration and the photoconductive paths. Optical energy is fed into an input optical waveguide and, dependent upon the optical inputs to the first and second photoconductive paths, an output is produced by the optical waveguide configuration in the manner of a logic gate. Variant configuration of the optical waveguide assembly can be made to perform in the manner of an AND gate, and OR gate, an exclusive OR gate, a NOR gate, or a NAND gate; alternatively, combination configurations can simultaneously perform multiple logic functions.

Abstract: A fiber optic delay line filter receives light energy input signals repretative of any form of temporally varying signals such as electrical or acoustical, for example. A plurality of fiber optic light paths each having a determinably variant optical propagation delay, receives and transmits the light energy signals. A photo responsive means receives the delayed output light energy signals transmitted by the plurality of fiber optic light paths and produces a single electrical output signal as a function of the sum of the delayed output light energy signals, thus performing a filtering or correlation function. In a preferred embodiment, an injection laser or light emitting diode may be employed as the means for converting the temporally varying input signals to commensurate light energy signals.

Abstract: An aspect ratio and scan converter system adapts signal information derived rom optical scanning of a rectangular field of view having an aspect ratio of the order of 60 to 1. The signal information is converted to digital form and serially stored in a bulk storage memory which may be addressed for reading out selected sequences of the serially stored digital signals. The selected sequences are stored in a random access memory having a two dimensional format and then read out by repetitive scan in a direction orthogonally related to the direction in which the sequences were stored. The digital signals thus read out are converted to analog form and applied to a suitable display means such as a TV type monitor CRT, providing a visual display of the selected portion of the elongate field of view.

Abstract: An optical waveguide of photoconductive material is positioned parallel to t least one other optical waveguide of electrooptical material. A first electrode is positioned between the two optical waveguides and second and third electrodes are positioned contiguous to the optical waveguides and opposite the first electrode. A constant amplitude electrical source is connected to the second and third electrodes and when light energy signals representative of a column vector function are propagated along the photoconductive optical waveguide, a commensurate change of conductivity between the first and second electrodes is caused to occur with a consequent change in electrical potential across the second and third electrodes embracing the optical waveguide of electrooptic material. When light energy signals representative of a row vector function are propagated along the second optical waveguide, a polarizatin modulated output signal is developed by the second optical waveguide.

Abstract: A complex spatial filter is provided by the combination of two dichroic ctal plates, one quarter waveplate, and two linear polarizers. The complex spatial filter consists of real and imaginary parts, both of which can have either a positive or negative sign and the structure is capable of eraseably recording varying degrees of absorbency which exhibit polarization discrimination in a desired format that can then be used to process the Fourier transform of a light beam containing desired information.

Abstract: A miniature optical lens for coupling is fabricated from selected high rective index semiconductor material of uniform thickness. Refractive index gradients are generated in the semiconductor material through changes in composition developed under controlled conditions producing a desired focal length for determinable wavelengths of light energy emitted from a light source to which the miniature optical lens is coupled. The miniature optical lens thus fabricated is especially efficient for coupling light energy from light emitting diodes and junction lasers as well as in semiconductor micro-optics within the visible and the infrared wavelengths as well because the index of refraction of the lens material may be closely matched to the index of refraction of the light source, minimizing light energy transfer losses.

Abstract: An optical switch affords the selective coupling of any of a plurality of input light signals to any of a plurality of optical output paths. A first plurality of ports circumferentially disposed in a first common plane supports means for transmitting and/or receiving optical signals. A second plurality of ports similarly circumferentially disposed in a second common plane having the same central axis as the first common plane, supports means for transmitting and/or receiving optical signals. A rotatable assembly is mounted on a common support structure with the input and output ports and has first and second members which are independently movable about the central axis.

Abstract: Single filament fiber optic cables are aligned within a connector to prov low-loss light transmittance from one to the other. Since it is virtually impossible to drill holes in a connector as small as the five thousandths of an inch typical diameter of a single filament fiber optic cable, the fiber optic cable ends are bonded within a section of micro-tubing, of the stainless steel type used for the micro syringe portion of a hyperdermic needle. The single filament fiber optic cable ends thus bonded within the micro-tubing, are received within terminal members of a selected metal material having internal bores which are readily drilled by conventional means to receive the micro-tubing having the ends of the fiber optic cables bonded therein. This assembly is made by force fit and each such assembled terminal of the single filament fiber optic cable is optically ground and polished at its end.

Abstract: An all-weather, maximum resolution system visually presents a multi-color mposite image of plural selected spectral ranges of energy received from a common field of view. First, second, and third images of a selected common field of view are developed and respective, first, second and third sensors (each responsive to a different spectral range of energy) develop first, second, and third sets of electrical signals commensurate with the energy emanating from the selected common field of view. In a typical preferred embodiment the selected spectral ranges may comprise the visual range of light energy, the middle infrared range comprising light energy in the 3 to 5 micron region, and the far infrared range comprising light energy in the 8 to 10 micron region.

Abstract: An optical waveguide arrangement operates in the manner of an interferometer to provide modulator and/or switching functions. Two optical waveguide branches having a common connection diverge along a substantially coextensive distance and reconverge to provide first and second light paths of identical optical length. Conductive electrodes are disposed contiguous to at least one of the optical waveguide branches and are connectable through a controlling switch to a source of electrical energy for producing an electric field across the energized electrodes. In the absence of such electric field, light energy entering the two optical waveguide branches will propagate along identical optical path lengths and recombine constructively at the reconvergence of the waveguide branches.

Abstract: A wide angle narrowband optical filter is provided by an assembly in which a body member supports multiple absorption materials in a common optical path. Each of the multiple absorption materials contributes toward narrowing the spectral bandwidth region permitting transmittance of light energy. A bandpass glass color filter restricts light transmission to a relatively broad spectral range of approximately 250 nanometers and a selected coumarin dye material in solution used with a second solution of a selected rare earth material narrows the spectral range of transmittance. In a preferred embodiment an interference filter further narrows the transmitting bandwidth to approximately 12.5 nanometers at FWHM (measured at Full Width Half Maximum) in the spectral region which is desirably coincident with the wavelengths of light energy best transmitted in ocean waters.