Abstract: In an optical system comprising a pair of rigid (e.g., glass) lens elements 11 and 12 mounted coaxially within a hollow cylindrical housing 10 so as to define a gap therebetween, a liquid (which functions as a liquid lens element 13) is contained within the gap. The rigid lens elements 11 and 12 are bonded to corresponding interior surface portions of the cylindrical housing 10 by means of an adhesive material that also functions as a sealant to prevent leakage of liquid from the gap. The adhesive sealant material preferably consists of a fluorosilicone sealant marketed by Dow Corning Corporation of Midland, Mich. under the trademark DOW CORNING X5-8738.

Abstract: An open mesh material for use as a high performance RF reflective antenna surface and which is formed as a Leno type weave using electrically conductive composite yarns which have a construction for avoiding loose metal-to-metal contacts which generate undesirable passive intermodulation products (PIM). The composite yarns are formed by counter-wrapping stretch resistant nonconductive strands about an insulated metal strand and a stretch resistant nonconductive filler yarn. The insulated metal strand preferably includes a beryllium-copper wire which is encapsulated within a polyamide coating. The woven mesh is coated with a RF energy transparent silicone-based paint to provide additional insulation to the plastic coated wires at the weave junctions and has a surface resistivity sufficiently low to facilitate bleed off of building electro-static charges.

Abstract: Design forms are disclosed for 5X and 10X laser beam expanders whose lens elements consist only of plastic and liquid optical materials, which provide diffraction-limited performance without refocussing over a wavelength range from 0.4 micron to 0.8 micron.

Abstract: A method and apparatus for electrically generating sets of binary spreading-code sequences for use in a multi-node communication network are disclosed. A method for assigning disjoint sets of binary spreading-code sequences to different nodes of such a network is also disclosed. Each set of binary spreading-code sequences consists of multiple sequences, which are generated using two binary shift registers. The sequences can be generated simultaneously, or sequence segments can be generated sequentially. To generate sequences simultaneously, the contents of multiple pairs of stages of two linear-feedback binary shift registers are combined by modulo-2 addition, where each pair of stages consists of one stage from each of the two binary shift registers.

Abstract: A redeployable, furlable rib reflector which is furlable and unfurlable between a first stowed position and a second deployed position. The reflector includes a hub assembly having spaced apart top and bottom plate members adapted to receive an antenna feed assembly mounted thereon and a plurality of attachable modular rib assemblies spaced about a periphery thereof. Each modular rib assembly includes a rib member for supporting a metalized mesh reflector surface attached thereto, a channel section base member, and a hinge assembly for pivotally connecting the rib members to their respective channel section base members. The channel section base members, in turn, are attachable between the top and bottom plate members of the hub assembly and also form a portion of the peripheral wall of the hub assembly.

Abstract: Wavefront correction apparatus for correcting a stepped wavefront output produced by certain angles of scan and by certain positions of scan in scanning microlens arrays includes anamorphic transfer optics with diffractive corrections. The transfer optics form the outputs of all of the unit cell trains of the microlens arrays into a unique, separate, linear image at each position of scan of the scanning array. A stepped wavefront corrector is positioned in the path of each linear image, and selected thicknesses of the material in the stepped wavefront corrector are effective to vary the times of optical passage through the stepped wavefront corrector in amounts to restore the wavefront to a continuous, unstepped form at the outlet of the plate.

Abstract: In an optical system comprising a pair of rigid (e.g., glass) lens elements 11 and 12 mounted coaxially within a hollow cylindrical housing 10 so as to define a gap therebetween, a liquid (which functions as a liquid lens element 13) is contained within the gap. The rigid lens elements 11 and 12 are bonded to corresponding interior surface portions of the cylindrical housing 10 by means of an adhesive material that also functions as a sealant to prevent leakage of liquid from the gap. The adhesive sealant material preferably consists of a fluorosilicone sealant marketed by Dow Corning Corporation of Midland, Mich. under the trademark DOW CORNING X5-8738.

Abstract: A large aperture microlens array assembly has at least two arrays of microlenses with individual unit cell trains optically interconnecting individual microlenses in one array with related individual microlenses in another array. In each unit cell train the light entering an entrance pupil of a microlens in one array is transmitted through the exit surface of a related microlens of the other array to provide a collimated output through the exit. One array may be moved with respect to the other array for scanning a field of regard.

Abstract: Novel acceptor-donor-acceptor compounds for use in forming a thermally-stable electro-optic waveguide are disclosed. Also disclosed is a thermally stable waveguide material containing thermally stable acceptor-donor-acceptor or donor-acceptor-donor guest dipole compounds in dissolved form in a polyimide matrix. The waveguide has selected regions in which the net dipoles of the guest molecules are oriented, for electro-optic switching when an electric field is placed across these regions.

Abstract: A launch vehicle (e.g., a rocket) carrying a payload consisting of:1) a first set of one or more satellites for delivery to a designated first orbit in a first orbital plane, and2) a second set of one or more other satellites for delivery to a designated second orbit in a second orbital plane,is launched from earth in a conventional manner to an orbit in the first orbital plane where the satellites of the first set are released into the designated first orbit in the first orbital plane. Then, after the first set of satellites has been released, a first acceleration is imparted to the launch vehicle to change the inclination and the longitude of the ascending node of the launch vehicle by an appropriate amount so as to cause a nodal drift of the launch vehicle from the first orbital plane to the second orbital plane over a specified time interval.

Abstract: This invention relates to terbium activated silicate luminescent glasses exhibiting reduced afterglow and enhanced luminescence due to incorporation therein of selected rare earth oxides of cerium, europium and gadolinium.

Abstract: Design forms are disclosed for 5X and 10X laser beam expanders whose lens elements consist only of plastic and liquid optical materials, which provide diffraction-limited performance without refocussing over a wavelength range from 0.4 micron to 0.8 micron.

Abstract: Integrally formed grid structures made of composite graphite-epoxy material are disclosed in which graphite fibers extend three-dimensionally in at least three different directions.

Abstract: An adaptive control includes a digital error correction system (DECS) to reduce control system error to near zero by anticipating a problem and feeding forward in time a correction to deal with the problem before it happens. The adaptive control is used in a controlled system of the kind which is cyclical in operation and which operates in response to repetitive cycle commands so that the operation of the system is substantially predictable for a significant number of cycles of operation. The adaptive control is incorporated in a spatial chopping or scanning telescope system of the kind in which a telescope mirror is moved in repetitive cycle motions and in a rigidly prescribed pattern between varied orientations and wherein the mirror is held for a prescribed, relatively long period of time in each orientation and is moved rapidly in a relatively short period of time from one orientation to another.

Abstract: A grid structure with sinuous interstices comprises intersecting grid sections having undulate surfaces. The intersecting grid sections of the grid structure are made of a composite material consisting of fibers (e.g., graphite fibers) embedded in a matrix (e.g., epoxy resin).

Abstract: A path analyzer for determining if a specified path is blocked by a given solid obstacle in three dimensional space. A programmable comparator converts path endpoints into first and second map signals, wherein each map signal indicates whether the corresponding path endpoint's position on predefined X, Y and Z coordinate axes is above, below or within a range of coordinate values associated with a specified obstacle. The specified obstacle is modelled as a rectangular parallelepiped, regardless of the actual shape of the obstacle. A first high speed decoder uses these map signals to make an initial determination as to whether the specified path is blocked, not blocked, or may be blocked by the specified obstacle. Whenever the first decoder determines that the path may be blocked, a second decoder determines the minimum number of additional computations needed to resolve whether the specified path is blocked.

Abstract: Optimized design forms are provided for glass-liquid lens triplets for use as telescope objectives having reduced secondary spectrum. Each lens triplet comprises an abnormal-dispersion liquid lens element contained between two normal-dispersion glass lens elements. The glass lens elements are made of readily available and relatively inexpensive optical glasses. The liquid lens element in each lens triplet consists of a commercially available viscous supercooled liquid of abnormal dispersion, which is transparent to optical radiation at visible wavelengths without freezing at temperatures in a range from about -50.degree. C. to about 50.degree. C.

Abstract: Integrally formed grid structures made of composite graphite-epoxy material are disclosed in which graphite fibers extend three-dimensionally in at least three different directions.

Abstract: Integrally formed grid structures made of composite graphite-epoxy material are disclosed in which graphite fibers extend three-dimensionally in at least three different directions.

Abstract: A 5.times. laser beam expander lens that is well-corrected for chromatic aberration can be used without refocussing over a wavelength range from 0.365 micron to 1.3 micron.