Abstract: A scanning system (10) and a method permit scanning a desired field-of-view within a maximized field-of-regard at a constant speed without reversing the scan direction about a primary axis (38). The system includes a mirror (20) which rotates about the primary axis (38). The mirror (20) is supported for rotation about a flip axis (40) which is perpendicular to the primary axis (38). Rotation of the mirror (20) about the primary axis (38) is divided into a scan period during which the field-of-view is scanned by the mirror (20), and a flip period during which the mirror (20) rotates about the flip axis (40). The mirror (20) is mounted in a gimbal for independent rotation about a secondary axis (24) which is parallel to the primary axis (38).

Abstract: A frequency jitter compensation radar system which frequency modulates a transmitter laser beam with simultaneously generated up- and down-chirped frequency modulated signals. The frequency modulated transmitter beam is used to scan a target and a reflected light beam is received for each pixel location of a radar system. The reflected light beam is heterodyned with a local oscillator laser beam and upon detection two separate electrical signal channels are provided representing tb up- and down-chirped frequency modulated signals. These up- and down-chirped signal channels are compressed and are further processed as the return signals of a radar system as by averaging the peak detection measurement from the two channels for each pixel to provide frequency jitter compensation commonly resulting from speckle from a target. Electro-optic or acoustic-optic arrangements may be used to frequency modulate the transmitter laser beam.

Abstract: Fabrics are cleaned by treating at least a portion of the piece of fabric with a particulating chemical, and agitated by a gas jet of a particle-dislodging gas to dislodge the particulated soil. The particulating chemical loosens embedded non-particulate soil and converts it to a particulate form, which is then separated from the fabric by the particle-dislodging gas.

Abstract: A compact, high numerical aperture, high resolution, ultra-wide field of view concentric scanning optical sensor. In a most general embodiment, the inventive optical arrangement (10) includes an at least semi-spherical lens (14) having a base; a reflective surface (16) centered at a center of said base and parallel thereto; and an array (20) of detectors dispose to receive electromagnetic energy received through said lens and reflected by said surface. In the illustrative embodiment, the semi-spherical lens is a ball lens (14). The reflective surface is aspheric and designed to effect aberration correction. A mechanism (19) is included for rotating the ball lens (14) causing the system to scan. A dome lens (18) is disposed over the ball lens and concentric therewith. Electromagnetic energy is received through the dome and ball lenses and reflected by the mirror to the detector array. A field lens assembly (21) is disposed between the detectors and the mirror.

Abstract: An optically-pumped laser having a gain medium configured to provide a low loss, three-dimensional integrated optical pump cavity that substantially confines optical pump radiation within the lasing volume, which is particularly useful for efficiently pumping solid state gain media that has low pump dopant concentration. The integrated pump cavity includes a plurality of boundaries contiguous with the gain medium. An optical pump source such as a laser diode array supplies optical pump radiation that is input into the gain medium through one or more pump cavity windows with a propagation direction transverse to a laser axis defined through the gain medium. In some embodiments, an optical surface is situated opposite the window to approximately recollimate the input pump radiation. The optical pump cavity may be designed to concentrate the optical pump radiation and approximately uniformly pump the entire volume of the lasing medium.

Abstract: A concentrator including a volume of at least partially transmissive material and a plurality of facets disposed at at least one surface thereof. Each of the facets is disposed at a position dependent angle relative to the surface effective to cause an internal reflection of energy applied to the layer whereby the density of the applied energy varies as a function of position. In the illustrative implementation, the volume is an active medium, i.e., a slab. The slab has substantially parallel, planar upper and lower surfaces and first and second edges therebetween. A plurality of cladding layers are disposed on the upper and lower surfaces of the slab. The facets are provided in the cladding layers on the upper and lower surfaces of the slab and angled as a function of distance relative to the first or the second edge. The facets provide a Fresnel reflecting surface or a binary optic surface.

Abstract: An external pupil lens system (200) with an entrance pupil distance at least three times that of the effective focal length. The lens system is comprised of several conventional lenses and a diffractive optical element (DOE) for secondary chromatic aberration correction. In the illustrative embodiment, the system includes an entrance pupil (50), followed by a lens group (52) containing two refractive elements for primary color correction. Next along the optical axis is lens group (54), which contains two refractive elements for astigmatism and higher order coma correction, followed by lens group (60), which contains one refractive element (62) and one DOE (64) for secondary color correction.

Abstract: A collimating optical device utilizes a reflective beamsplitter in the form of a linear polarizing beamsplitter to achieve a wide field of view. One form of the wide-angle collimating optical device includes, in order from an image source, a first absorptive linear polarizer; a first quarter-wave plate; an optical doublet including a piano-concave singlet, a plano-convex singlet whose convex surface has the same curvature as the curvature of the concave surface, and a first reflective beamsplitter joining the concave surface of the plano-concave singlet to the convex surface of the plano-convex singlet; a second quarter-wave plate; and a second reflective beamsplitter. One of the reflective beamsplitters is a linear polarizing beamsplitter, most preferably a wire grid polarizer.

Abstract: An incoherent ladar transmitter (12) adapted for use with synthetic aperture processing. The system (12) includes a first mechanism (44, 48, 50) for generating a laser beam (18). A second mechanism (44, 68) records phase information pertaining to the laser beam (18) and subsequently transmits the laser beam (18) from the system in response thereto. A third mechanism (40) receives a reflected version (20) of the laser beam and provides a received signal in response thereto. A fourth mechanism (72) corrects the received signal based on the phase information recorded by the second mechanism (44, 68). In a more specific embodiment, the ladar system (12) includes a synthetic aperture processor (46) for correcting the received signal based on the phase information and providing a corrected laser signal in response thereto.

Abstract: A sensor system includes a sensor, and an optical train adjustable to provide an optical beam to the sensor from a selected line of sight that may be varied. The optical train includes a wavefront error-introducing element in the optical train, which introduces a wavefront error that is a function of the selected line of sight. There is further a rigid-body wavefront error-correcting element in the optical train. The rigid-body wavefront error-correcting element has a spatially dependent correction structure with the nature of the correction being a function of the selected line of sight. The adjustment of the optical train to the selected line of sight moves the optical beam to the appropriate location of the rigid-body wavefront error-correcting element to correct for the corresponding introduced wavefront error of the wavefront error-introducing element at that selected line of sight.

Abstract: A launch canister for a missile, including an outer canister shell and a concentric inner liner. The inner liner augments the canister shell with structural load capability and bending inertia to enhance canister stiffness. The inner liner can be constructed from structural load carrying composite materials, and also acts as a thermal and ablative insulator to enable vertical plume venting away from the enveloped missile. A shock and vibration isolation layer can be laminated between the inner liner and canister shell.

Abstract: A fuzzy controller (130) for use in target detection systems. The fuzzy controller (130) includes a first circuit (132) for determining a number of false alarms in a frame of data. A second circuit (136) determines a desired number of false alarms for the frame of data. A third circuit (134-152) computes a threshold multiplier factor based on the number of false alarms, the desired number of false alarms, and one or more fuzzy rules. In a specific embodiment, the first circuit (132) includes a target detection system for providing addresses of pixels whose values are within a predetermined range relative to a detection threshold. The second circuit (136) includes an input device (136) for accepting the desired number of false alarms as input to the fuzzy controller (130). The third circuit (138-152) includes a fuzzifier input calculation circuit (134) that computes a fuzzifier input value based on the number of false alarms detected in a frame and the desired number of false alarms.

Abstract: An integrated detector and signal processor (31) for ladar focal plane arrays (30) which internally compensates for variations in detector gain, noise, and aerosol backscatter. The invention (31) is comprised of a detector element (42) for receiving an input signal, a circuit (72) for generating a threshold based on the RMS noise level of the input signal, and a circuit (74) determining when the input signal is above that threshold. The detector element (42) is physically located in the interior of the detector array (30), while the signal processing circuitry (50) is located on the periphery of the array (30). In the preferred embodiment, the signal processor (31) also includes a circuit (56) for sampling the input signal and a circuit (58) storing multiple samples, allowing for multiple returns to be detected. In the preferred embodiment, the signal processor (31) can be operated in two modes: self triggered and externally triggered (range-gate mode).

Abstract: A millimeter-wave window is constructed from a high conductivity metal plate. The metallic plate is made transparent over a range of frequencies by perforating it with a periodic array of slots. In one embodiment, the millimeter-wave window is used in a gyrotron as the output window. In such a case, one suitable periodic array of slots comprises an equilateral triangular array of slots for operation at 95 GHz. By proper choice of the hole spacing and diameter, the window can be made transparent at any desired frequency. In addition to being transparent, however, the window must also be vacuum tight, as the pressure inside a gyrotron is on the order of 10−9 torr. The present invention solves this problem by covering the surface of the window with a thin layer of a suitable dielectric material, such as fused quartz.

Abstract: A wavelength conversion system and method. The inventive system is adapted to receive a beam of input energy having a first spiked portion with a first wavelength and a first spatial and/or temporal intensity profile and a second tail portion with the first wavelength and a second spatial and/or temporal intensity profile. The inventive system includes an electro-optic switch (14) and first polarizer (16) for directing the first portion of the input beam along a first processing path (18) and a second portion thereof along a second processing path (20). A first SHG/OPO arrangement (22, 24) is disposed in the first path (18) for shifting the wavelength of the first portion of the input energy from the first wavelength to a second wavelength. The first arrangement is optimized for the first spatial and/or temporal intensity profile of the first portion of the energy.

Abstract: A signal divider/combiner (11) and method combines first and second frequency signals received by microstrip patch antennas (58, 48). A first transmission line stub (28) blocks the second frequency signals on the first signal receiving path, and a second transmission line stub (20) blocks the first frequency signals on the second signal receiving path providing increased signal levels at a receiver input (10). In one embodiment, the transmission line stubs are open-circuit stubs and are positioned a quarter-wavelength from a combining junction (12) formed from stripline transmission lines (14, 32, 50). The transmission line stubs (28, 20) also reduce radiation of the first frequency signal by the second antenna as well as radiation of the second frequency signal by the first antenna. In one embodiment, the first and second frequency signals are the L1 and L2 signals provided by the Global Positioning System.

Abstract: A birdcage-shaped harness assembly adaptable for electrically connecting a bulkhead support structure with a rotatable gimbal support structure. In order to avoid excessive torsional forces from acting on the harness, a plurality of conductor portions are bundled together and pre-compressed in length between the support structures. When assembled, the conductor portions of the harness assembly form a birdcage-shaped dynamic bundle wherein the middle of the conductor portions bow away from conductor portions on the opposite side of the bundle. This pre-compression creates a birdcage-shaped configuration that allows the bundle to bend as the conductor portions straighten. This occurs when the gimbal rotates relative to the bulkhead. The bending motion creates relatively little damage to the conductor strands as compared the excessive torsion forces affecting conventional loop-shaped wire harness assemblies.

Abstract: A method an apparatus for inducing spin, or rotation, in a dispersed payload of a non-spin guided projectile is taught. Rifling is applied to a cylindrical surface of a projectile casing. The rifling engages a member on a payload, which may be a bulkhead, as the payload is expelled from the projectile casing. The rotation imparted to the payload causes the dispersed projectile, grenades in the preferred embodiment, to form a spiral pattern that provides a more uniform coverage of the target area as compared to the prior art.

Abstract: The present invention related to a universal joint assembly for attaching two missile sections together wherein one section is a recycled rocket motor. The joint assembly includes a plurality of attachment blocks each secured through fasteners to the outer surface of the rocket casing. Separate fasteners are employed between the attachment blocks and the adjacent section. As the fasteners are advanced, the attachment blocks are first secured to the rocket casing and then the attachment blocks are drawn toward the adjacent section until the sections are abutting one another. The attachment blocks do not abut the adjacent section.

Abstract: An ultra-wide band general purpose analog to digital signal processor (200) covering the radio frequency range from 20 MHz to 5 GHz. The processor (200) includes a first circuit for shifting a frequency of an input signal, a second circuit for processing the input signal, and a third circuit for selectively bypassing the first circuit whereby the input signal is provided directly to the second circuit in a first mode of operation and to the second circuit via the first circuit in a second mode of operation. In the illustrative embodiment, the first circuit is a mixer (12) with a normalized mixing ratio of 0.8 to 0.9. The second circuit is a sigma-delta analog-to-digital converter (14). The third circuit is a switch (10) for passing the input signal directly to the second circuit if the input is 20 MHz to 2 GHz, or for passing the input signal to the first-circuit if the input is 2 GHz to 5 GHz.