Abstract: A multiple light valve (MLV) projector apparatus for producing a color display includes two separate light valves of the Schlieren dark field type. One of the light valves produces a first primary color, for example green, and the other light valve produces two other primary colors, for example red and blue. In such an apparatus the output brightness is usually limited by the red light output. An improved input (and complementary output) mask is described which optimizes the transmission of the first, second and third diffraction orders through the slots in the portion of the input mask which transmits red light. Such an optimization provides a substantial increase in red light output compared to a conventional input mask.

Abstract: The areal height and areal reflectivity of source data for defining a landmass are modified in real time in response to the areal reflectivity of the source data, so that the modified values may be processed for generating radar images to be displayed. The images may include stationary three-dimensional features, useful for a high resolution radar, without need to preprocess data or increase bulk storage medium size of landmass data. In addition, the features, which may include industrial, forestial, commercial and/or residential areas, and/or specific detail such as a predetermined airport, may be predeterminedly disposed within a landmass area more realistically to present an image that is to be expected from an actual operating environment.

Abstract: An improved electron deflection system for a light valve of the type used in Schlieren dark field projectors is disclosed. The deflection system eliminates one set (D box 25) of three sets of deflection electrodes used in such projectors. This is accomplished by modifying the d.c. voltages and a.c. voltages applied to the deflection electrodes. A quadrupole d.c. voltage is added to the first control box set of electrodes (61, 62) and a second quadrupole voltage of opposite sense is added to the focus deflection box set of electrodes (63, 65). This modifies the vertical and horizontal beam angles differentially and the vertical and horizontal beam trajectories differentially in a manner to compensate for the composite effects of spherical aberrations, deflection focusing aberrations, and the static starfish lens generated by the interaction of the square box electrode structure against the round drift ring assembly (21) of the deflection system.

Abstract: Improved masking of light valve spill light is disclosed for Schlieren dark field light valves. The mask is deposited on the interior or exterior of the output window (58) and comprises an opaque area (90) which surrounds a transparent window area (91). The mask is characterized by a zone (92) of graduated density from transparent to opaque. The effect of the graduated density zone is to eliminate spurious light diffracted by the edges of the mask and significantly improves the performance of the light valve.

Abstract: An electrostatic precipitator is provided in a light valve of the Schlieren dark field type. The electrostatic precipitator comprises two conductive surfaces within the fluid reservoir of the light valve. One of these surfaces may be the filter housing (81), and the other may be a metal coating (105) which is applied to the inner glass surface of the rear housing (53) of the light valve. By applying a constant d.c. potential across these two conductive surfaces, a resinous or lacquer build-up occurs which is composed of the fine colloidal particulate wear material and a fluid related component which are produced as a result of the normal operation of the light valve. Both the wear material and the fluid related component are too fine to be filtered by mechanical means. Because the wear material and the fluid related component form an adherent resinous material which bonds to the negative electrode, these particulates are permanently removed from the fluid.

Abstract: A computer video image generating system including a computer memory having three dimensional object data stored therein employs an advanced object generator for retrieving and processing the object data for output to a span processor for controlling the pixel-by-pixel video output signal for a video display. The advanced object generator includes a translucency processor, an edge-on fading processor, a level of detail blending processor and a bilinear interpolator for texture smoothing.

Abstract: A method for computer image generation producing simulated visual scenes for applications such as flight training, employing a comprehensive distortion correction to generate the image takes place in three sequential stages: Controller, Geometry Processor, and Display Processor. The Display Processor generates video to produce the desired scene on the raster of the display device. If the scene is projected through a wide-angle lens and/or is projected onto a curved screen, the combination of optical and geometric distortion presents a highly distorted scene to the viewer. The comprehensive distortion correction method produces a precisely predistorted scene on the projector raster so it appears valid to the viewer. Mapping between projector space and viewer space is highly nonlinear. However, a small region of the display (span) is selected sufficiently small so that the projector/viewer transformation may be considered linear.

Abstract: A technique for the real-time computer generation of visual scenes of rolling terrain and sea waves is based on a view ray approach wherein an azimuth sweep is defined and an image profile is generated by incrementing range steps from the view point but employs a data base which is an on-line math model consisting of a summation of cosine functions rather than a grid data base. Math models are generated separately for both land and sea elevation posts for the scene to be generated. A horizontal field of view is defined as a predetermined number of increments between sweeps perpendicular to a boresight from a view point, and a vertical field of view is defined as a predetermined number of increments between view rays perpendicular to the boresight from the view point. The change in range is incremented along the boresight from the view point, and for each range increment, the view ray is stepped down by an increment corresponding to an incremental change in the tangent of the view angle.

Abstract: An improved advanced video object generator with a more efficient cell texturing memory is disclosed. The advanced video object generator includes a data memory for storing cell-by-cell object data for a plurality of objects for retrieval and processing for video display. A vector processor calculates object transformations for translating operator inputs into image orientation control signals for calculating pixel-by-pixel image data. Cell texture address logic determines the memory location to be accessed for retrieval of cell texture data for display. Output logic provides the cell texture data to a span processor which translates the cell texture data into pixel-by-pixel display data for display on a video display device. The disclosed improvement includes at least one data memory hardware map having a plurality of nxn memory locations for storing n.sup.2 cell sets of cell texture data. The cell texture output logic reads out two independent n.sup.2 cell sets simultaneously which are blended.

Abstract: An area of interest display system of the type wherein area of interest imagery of relatively great detail and resolution is displayed in the spatial position of the foveal region of the eye of an observer and background imagery of relatively lesser detail and resolution is displayed about the area of interest imagery is disclosed. An improved display is achieved by optically blending and projecting the area of interest imagery and the background imagery with a common servo optical system.

Abstract: Elongated, one-piece molded plastic supports are affixed in vertically spaced relation to the front of a printed circuit card frame assembly backplane equipped with a plurality of card connector receptacles. Each support is formed having a forwardly facing tongue and groove formation along the length thereof which mates with a complementing tongue and groove formation formed along the rear edge of a one-piece molded plastic shelf. A retainer rod, inserted through aligned openings in the support and shelf tongues, sustains the assembly. Guide tracks in the upper and lower surfaces of vertically adjacent shelves accept printed circuit cards for plug-in electrical connection with the backplane receptacles.

Abstract: A color graphic overlay system for providing high speed, high resolution color graphics display combined with a video image from a videodisc, videotape or camera. The system includes a video mixing module and a color graphics module which generates the graphics while the video mixing module performs the overlay function. A composite sync processor filters an external video composite sync signal to produce a processed horizontal sync pulse that is phase adjustable and ultimately used by a phase lock loop to lock the horizontal component of the external video composite sync signal to the horizontal component of the graphics composite sync. The phase lock loop employs the processed horizontal sync pulse to generate a high frequency clock used by the color graphics module to produce its own horizontal sync pulses.

Abstract: A tuned coriolis, angular rate measuring device includes a substantially hollow, generally annular rotor driven by a high-speed, synchronous spin motor. The rotor is made unsymmetrical by mounting within the rotor near its periphey at least a pair of high density masses, the respective masses being located diametrically opposite one another. The rotor is secured within a gimbal structure which is, in turn, mounted in tuned fashion upon a support housing through a cantilever spring at each end along the gimbal output axis, thereby providing bearingless, frictionless pivots permitting limited gimbal rotation. A pair of piezo-electric crystals is secured at opposite edges of one of the springs for sensing relative angular motion between the gimbal and the housing. The crystals are electrically paralleled so as to cancel any signals resulting from linear movement between the gimbal and housing.

Abstract: An optical fiber position sensor includes an optical fiber cable wound in the shape of a single layer, tightly wound coil, the coil being secured to a first member. A second member, which is linearly movable with respect to the first member, has fixed thereto an LED which is aimed at the coil such that radiation being emitted from the LED is injected approximately tangentially into the coil. Radiation being transmitted through the coil is attenuated as a function of the distance that it travels therethrough and as a result, radiation exiting the coil through the terminations is representative of the location of the movable member with respect to the fixed member.

Abstract: A video processor that provides non-linear amplification of an input video signal by automatically modulating a non-linear transfer function of an amplifier having a plurality of piece-wise, analog-to-digital (A/D) converter sections. Each A/D converter has both high and low reference levels set at the input break points of the non-linear transfer function to assign an equal number of shades or levels of gray thereto. The high and low reference levels are connected in a "totem pole" configuration with the high reference level of the first converter providing the low reference level to the second converter, and so on for the remaining converters.

Abstract: An optical fiber position sensor wherein a first member is rotationally movable with respect to a second member. A generally rod-shaped fiber optic cable is provided having two elongated portions in close axial alignment. The interface surfaces of the two portions have equal face angles of approximately 30-35 degrees from the longitudinal axis. One of the cable portions is secured to the first member and the other cable portion is secured to the second member.

Abstract: An automated testing apparatus which performs shorts and continuity testing on a printed circuit board or ceramic substrate submerged in an ionic conducting solution is disclosed comprising a central controlling device which interfaces with an electrical measuring instrument, a numerical control table to position a moveable probe over the unit under test so as to measure its electrical characteristics, and a strip printer to display results.

Abstract: A visual display system and method for use in converting calligraphic symbology information into raster scanned symbology. The system simultaneously generates and displays calligraphic and raster matrix imagery utilizing the same set of software instructions. The imagery is displayed upon a single, hybrid calligraphic/raster matrix display or separate raster matrix and calligraphic displays. A programmable calligraphic symbology generator utilizes digital stroking techniques that successively generates addressing for a matrix arrayed memory and determines the attributes of both the raster matrix generated and calligraphic generated symbology. The information is stored in a single or a plurality of matrix arrayed memories according to desired symbol attributes and system performance.

Abstract: A PN sequence signal estimator is described which synergistically co-operates with an adaptive array processor and a spread spectrum communication system modem such that the adaptive array will null interfering signals, but not desired signals. This is accomplished with the signal estimator generating an estimate of the desired coded signal through the use of the local code and the detected correlation in the modem, and feeding the estimate back to the array in such a manner that it subtracts from the array error voltage, thereby inhibiting null formation.

Abstract: 1. A transmission frequency diversity radar system comprising an oscillator that is tunable over a frequency band to produce a signal for radar transmission, means for tuning said oscillator randomly on a random frequency basis, and means for frequency tracking the signal being transmitted including a variable frequency local oscillator, means to sweep the local oscillator over a range of frequencies within the pulse width time of the radar transmitted signal but after said transmission oscillator is tuned and modulator means responsive to the transmitted signal for holding said variable local oscillator on the proper tuning frequency.