Abstract: Polarization phase plate Assembly comprises at least two uniaxial crystal plates which are identical to each other in structure and dimension and a retarder plate sandwiched between the two uniaxial crystal plates. Initially the optic axes of the crystal plates are aligned to be parallel with each other. Then the plates are subsequently rotated around the normals of the plates by an equal twist angle but in opposite directions. When a beam of light is passed through the assembly post-twist, the result is high-quality fringes that are straight, smooth and capable of exhibiting close to 100% contrast. The fringes have a sinusoidal cross-fringe profile and vary in number in relation to the degree of the twist angle.

Abstract: The Multispectral-Hyperspectral Sensing System (MHSS) comprises a control center, a surveillance platform and at least one weapon battery with known sensing and destroying capabilities. The control center has access to pre-existing information relating to the target scene and potential targets, although not necessarily current, as well as the capabilities and limitations of the available weapons. This pre-existing information is communicated to the surveillance platform to be used in collecting hyperspectral/multispectral image data of the target scenery and to derive from the collected image data the relevant current target data subset. The derived data subset is then down-linked to the control center, which performs further processing to make it useful to the selected weapon. The weapon receives the target signature update from the control center and, in response, performs a significantly more precise strike at the selected target than based just on the a priori knowledge base.

Abstract: A system is disclosed for generating simulated radar targets that eliminates the necessity for large outdoor test ranges and is relatively low in cost. The simulated radar target generating system provides complex targets of given simulated dimensions at given simulated distances when stimulated by signals emitted by the radar sensor in the sensor's operational frequency. The dimensions are simulated by the use of multi-tap delay device while the distances (or, range) are simulated by routing the signal, in the form of light, through a fiber optic delay of a desired length. This system, which costs less than $50 thousand, can be located as close as eight feet to the sensor under test.

Abstract: By employing a high-repeatability optical switch that transmits input optical power selectively either to the standard or the unit under test (UUT), OPHASE presents a system for performing a rapid, repeatable comparison between the standard and the UUT. Further, the selective routing of beam traveling through one of the two output fibers that are coupled to the switch either to the standard or the UUT enables the elimination of much of the system uncertainty by enabling initial characterization of the ratio, Rp, and inequivalence, Im, between the power outputs of the multiple output fibers coupled to the switch. This characterization is accomplished by using an angled interface which is constructed so as to allow simultaneous coupling of the multiple output fibers to the angled interface and enable the power readout of all the output fibers at the standard. Rp and Im are then used to calculate the correction factor that reduces the total uncertainty level in the subsequent calibration of the unit under test.

Abstract: The millimeter-wave zoom antenna for guiding a beamrider hypervelocity missile uses varying range information derived from the flight of the missile toward the target as control signals for the beam control computer to perform electronically the zooming and the nutation of the millimeter wave guidance beam that emits from a phased array antenna so as to maintain a constant energy density at the missile receiver regardless of the actual distance of the missile from the launch platform at any given time.

Abstract: The polarization-resolving infrared imager employs the configurations of either first-generation (60 horizontal rows by 1 vertical column of detector elements (pixels)) or second-generation (at least 240 horizontal rows by 4 vertical columns of detector elements (pixels)) infrared imaging detector devices and polarization filters that work in conjunction with the infrared imaging detector devices to separate incoming infrared radiation into portions each having a different polarization orientation. Such polarization separation enables the production of visible images in which various aspects of the scene are differentiated. In the preferred embodiment using the second-generation infrared imaging detector device, polarization-filtering grids are integrated onto the detector. The detector elements in three of the four columns have coupled thereto polarization filtering elements to filter, respectively, horizontal, vertical and 45-degree polarizations of the incoming infrared radiation.

Abstract: The all-optical pulse generating and amplifying system utilizes a phosphor that is excited by input light of a first wavelength and, in response, emits light of a second wavelength. The light emitted by the phosphor illuminates a bistable element which, at a pre-fixed intensity of the phosphor-emitted light, switches from non-transmissive state to transmissive state, thereby allowing the exit of light (also of first wavelength) emitted by an output light source as light pulse output of the system. An inhibitory light that also passes through the bistable element during its transmissive state quenches the phosphor light emission and returns the bistable element to its non-transmissive state and re-starts the process toward the next transmissive state. By gating the intensity, via selected non-linearity of the bistable element, of the light output in proportion to the intensity of the input light, the system can also function as an amplifier.

Abstract: In the improved system for sled-track testing of explosive missiles having tandem warheads and crush switches, time delay boards are placed on the sled to operate in conjunction with the crush switches to detonate the tip charge and the main warhead. The actual detonation is triggered by on-board firesets, one to detonate each warhead, that are optically coupled through an opto-coupler interface board which generates fire pulses in response to inputs received from the crush switch and the time delay board. These fire pulses are, in turn, transmitted to and activate the firesets.

Abstract: In a flying object equipped with the wing deployer and locker, a torsion spring connecting the wing with the base deploys the wing upon the release of the object from its storage canister and, after the wing has reached a certain degree of deployment, a tapered tooth that protrudes from the base engages a matching slot in the wing boss to lock in the wing at the moment the wing obtains the fully-deployed position. The taper angle of the tooth and the slot compensates for manufacturing tolerances and provides a positive, solid locking action for the duration of the object's flight.

Abstract: Two liquid crystal display panels, stacked together into a flat compact unit, in conjunction with a dedicated processor producing the appropriate video signals to drive the panels, generates a pair of polarization-encoded left and right images and exhibits them as a stereo image that is viewable through a pair of standard polarized glasses. This makes it possible to obtain stereo effect at a video workstation or at a console by eliminating the bulky box-like setup or the need to project onto a screen.

Abstract: The scatterider guidance system is mounted on the flying object that is to e guided toward a more direct impact on the selected target. The system utilizes a designating beam of laser pulses that is emitted from the launch pad toward the target and atmospheric particles that scatter the laser pulses to calculate the guidance commands that lead the flying object to follow the laser beam closely. Upon detection by the scatterider sensors of the laser light that is scattered by the atmospheric particles, the perpendicular radial distance between the laser beam and the longitudinal axis of the object in flight is calculated by the onboard guidance electronics and subsequently used to generate the deflection commands. The deflection commands, in turn, are used to deflect aerodynamic control surfaces of the object such that the object approaches and stays close to the laser beam. This guidance system is activated as soon after launch as possible and continues until the object impacts on the target.

Abstract: The data-link and antenna selection assembly combines a group of conformal ntenna arrays with radio frequency (RF) detection, control and switching circuitry to provide up to 360 degrees of azimuth coverage for an aerial or terrestrial vehicle. The signal monitoring comprises signal detection and determination of signal frequency and strength. These are input to a switching controller which selects the best receive path and transmit path as a function of received signal frequency and strength. Use of conformal antenna arrays eliminates the requirement for cumbersome mechanical positioners.

Abstract: The semi-active laser (SAL) last pulse logic seeker utilizing a focal plane array is obtained by combining the semi-active laser last pulse logic sal processing using a single PIN photodiode with a staring imaging infrared (I.sup.2 R) focal plane array detector, such as InSb. The result is an improvement that renders the seeker capable of operating in three different modes: SAL only, I.sup.2 R only or simultaneous multi-spectral processing in SAL/I.sup.2 R. The improvement uses a single PIN photodiode detector with an imaging infrared focal plane array (I.sup.2 R FPA) detector to correlate the temporal laser returns of the former with the spatial laser returns of the latter which enables the SAL last pulse return, indicative of the true target, to be identified on the I.sup.2 R FPA. To facilitate the correlation process, the FPA can be divided into regions-of-interest (ROI) that are analyzed to determine which temporal laser pulse falls in which particular ROI.

Abstract: A space-fed phased array radar utilizes a network of improved Mach-Zehnder nterferometers to provide a space-fed, optically controlled millimeter wave/microwave antenna array that is capable of either one-way or two-way transmission. In the two-way communication relay mode, both ends of the relay link can remotely switch from a transmit to a receive mode and vice versa while, at the same time, steering the outgoing radiation beams on both sides of the relay so as to achieve maximum signal-to-noise ratio between the two terminals (i.e. signal stations) of the communication link. The improvements include receiving antenna with beam-scanning capability to receive millimeter or microwave signals from a first signal station, amplifiers to amplify outgoing signals prior to being radiated outwardly by transmitting antenna and a means to render the same antenna array capable of being used in a two-way transmit and receive mode.

Abstract: Synthetic discriminant function automatic target recognition system augmented by LADAR combines, through the synthetic discriminant function (SDF), the active LADAR data of the potential target object with the passive infrared imagery of the target and background. In doing so, the system not only recognizes and classifies the target but also provides the range profile of the target object by analyzing the amplitude of the reflected return signal when appropriate. The live target scene imagery in passive infrared is detected, filtered and subsequently complex multiplied with pre-existing synthetic discriminant function to produce a two-dimensional cross-correlated surface. Analogous process is performed on the active LADAR range and intensity images of the live target scene with corresponding pre-existing synthetic discriminant function for the same target pose and scale as in the passive infrared correlation step.

Abstract: The single channel transceiver with polarization diversity is a target detion and tracking system that results from combining the well-established technology of single channel transceiver with that of microstrip polarization-diverse antenna. The single channel transceiver with polarization diversity transmits a pair of pulses of a pre-selected polarization sense toward a target object and receives two scattered pulses of orthogonal polarizations in rapid sequence. Thereupon, a second pair of pulses, this time of opposite polarization, is transmitted and, again, two scattered pulses of orthogonal polarizations from this second pair of transmitted pulses are received in rapid sequence. Thus, the single channel transceiver with polarization diversity has the capability to obtain the complete scattering matrix of a target by use of four transmitted pulses.

Abstract: The purpose of a system for measuring the location and orientation of an ect is to align one object with another by simultaneously measuring the six degrees of freedom of the objects. The system accomplishes the purpose by employing a linear optical detector array sensor on the first object and a pre-selected target pattern on a second object to measure the six degrees of freedom and converting them to six position measurement via a microprocessor which has suitable algorithms residing in it. The six position measurements (azimuth, elevation, range, pitch, yaw and roll) are displayed for viewing by the operator who, then, manipulates the objects until pre-determined desired values of the six position measurements are obtained, indicating a complete alignment between the objects.

Abstract: The dual band millimeter-infrared fiber optics guidance data link presents nhanced seekers with the capability to see through cloud cover while exhibiting resolution that is adequate to strike high value targets. Such a seeker may use a bi-directional dual band data link in the form of a secure, high bandwidth optical fiber between the missile in flight and the ground station, offering the capability to transmit millimeter-infrared sensor data from the missile to the ground station and transmit missile guidance signals from the ground station to the missile over the same high bandwidth optical fiber. Both infrared and millimeter target signature data is made available in the ground station by the use of applicants' invention.

Abstract: The device and method for performing an optical Hall test provide means for on-destructive measurement of free carrier concentration or effective mass in semiconductor materials using Faraday rotation spectra. A beam emitted by a Fourier transform infrared (FTIR) spectrometer is transmitted through the sample that is mounted between a polarizer and analyzer and the opposite poles of a magnet before finally being incident on a detector. The ratio of the samples's transmission spectrum with the magnetic field on to that with the magnetic field off is converted, through a suitable mathematical formula, to Faraday rotation. The rotation is, then, plotted versus the square of the wavelength. The slope of the graph at longer wavelengths is directly proportional to the carrier concentration and the effective mass. With one known, the other can be easily determined.

Abstract: A wideband quasi-optical millimeter-wave resonator achieves a wideband frency operation by using a variable dielectric constant photoconducting lens in a Fabry-Perot resonator. Changing the dielectric constant of the lens creates an associated change in the resonant frequency for a given axial mode.