Abstract: A directional optical filter (41) is provided for a shadow mask color cathode ray tube (shadow mask CRT) (47) having a plurality of display elements on its face (49). Two sets of light absorbing planes are arranged at approximately 90.degree. from one another and serve to block light passing therethrough from an angle greater than a predetermined angle of viewing. In order to reduce moire patterns which would result from varying coincidences of the planes with patterns of phosphor dots on the shadow mask CRT (47), filter sheets (43, 45) containing the light absorbing planes are rotated so that at least one set of light absorbing planes is misaligned with a set of closely-adjacent phosphor dots by approximately 15.degree.. Advantages include the ability to provide a parallel light absorbing plane directional optical filter in association with a shadow mask CRT and an ability to control the range of preferred viewing angles to differing amounts substantially in the horizontal and vertical directions.

Abstract: An optical filter device is disclosed made up of a specially designed bandpass filter and a circularly polarizing filter and is typically used in front of the faceplate of a cathode ray tube in a high intensity ambient light environment, such as with navigation displays in some aircraft cockpits, to reduce the high intensity ambient light striking the phosphor of the cathode ray tube and thus effect a reduction in the level of the scattered light that causes a washout of the display thereon, thereby permitting observation of the display on the tube.

Abstract: A moving map display is provided to represent the location of a vehicle such as an aircraft on a video display of a map. Map images are scanned by a remote pickup unit (40) using flying spot scanning techniques to scan transparencies (51) of sections of the map. In order to increase the resolution of map images, each transparency (51) is divided into a plurality of sections and an image of the flying spot from a CRT (45) is superimposed simultaneously onto the nine sections, using an optical tunnel. In order to scan only the desired portions of these images and in order to produce a coherent display, the images are selectively gated "on", electronically or by using light shuttering techniques. In the preferred embodiment, four of a group of nine images are used to create a given display, although other combinations are possible.The resultant display is a composite video modulated raster derived from the scanned images on the slide (51).

Abstract: A Raster and Stroke Writing Deflection Amplifier Arrangement for a cathode ray tube (CRT) is disclosed which uses a conventional vertical oscillator and vertical deflection amplifier and a conventional horizontal oscillator and synchronous horizontal deflection amplifier, both driving deflection coils for providing vertical and low power horizontal scan operation for raster scan writing of data, and a flyback transformer and rectifier for providing the high D.C. voltage required by the CRT anode by rectification of high surge voltages created during horizontal retrace periods.

Abstract: A Color Separator for a Map Display Video Generator utilizing a Fresnel lens to expand a multicolor light signal output from a point of light scanned map film to a stationary area that entirely fills an input end of a bundle of optical fibers the other end of which bundle is divided into three smaller bundles. The light output from each smaller bundle is first passed through a colored filter to thereby separate the light into the primary colors red, green and blue. The separated light is then converted to an electrical signal by photomultipliers and used to generate a color video signal applied to a color cathode ray tube display to display the map thereon.

Abstract: A method for making a direction sensitive contrast enhancement filter for a shadow mask color cathode ray tube is disclosed to minimize the amplitude of moire interference patterns to unnoticeable or unobjectionable levels. For a particular color cathode ray tube phosphor dot size, the light transmission through a direction sensitive enhancement filter having a given hole size and spacing is determined mathematically. The filter is then moved a number of fixed increments with respect to the phosphor dot and the light transmission is determined for each incremented position. The variation in light transmission as the filter is moved incrementally across the phosphor dot is the data recorded. This procedure is repeated for different hole sizes and different hole spacings and the data graphed to find the minimum light transmission variation. At this minimum light transmission variation moire patterns are reduced to unnoticeable or unobjectional levels.

Abstract: A moving map display used on an aircraft or other moving vehicle is disclosed. Discreet map segments are stored on a video signal storage means and portions of the video signals for several map segments are read from the storage means and combined to create a composite map segment which is displayed within the aircraft or other moving vehicle. A navigation system on the vehicle provides position information to a microprocessor which functions with other circuitry to determine which map segment portions are to be combined to create the composite map segment.