Abstract: A multiple-beam field sequential color (FSC) display system is provided for receiving a stream of digitized single-beam image data to display a color image by employing a plurality of CRT guns to project multiple beams on a monochromatic CRT screen followed by converting a monochromatic refection from the CRT screen to the color image by using a liquid crystal color system (LCCS). The multiple-beam display system includes a multiple-beam image data memory which includes a plurality of data-banks. The multiple beam display system further includes an image data rearranging processor for rearranging and storing the plurality of digitized single-beam image data in the multiple beam-image data memory according to a pre-designated multiple-beam sequence in each of the data-banks.

Abstract: A virtual image display system with reduced ambient reflection. The virtual image display system includes a black and white image source for projecting a black and white image. The black and white image is then projected to a magnifying virtual image optical arrangement including a concave reflecting mirror. The magnifying virtual image optical arrangement and a color shutter including a linear polarizer receive the black and white image to generate a magnified color virtual image. The virtual color image display system further includes a .lambda./4-plate for cooperating with the color shutter including the linear polarizer to reduce an ambient reflection from the concave reflecting mirror.

Abstract: A compact, inexpensive and mass-producible optical display system for an automobile creates a dramatic and highly stylistic, sharp, high contrast and pleasing, multi-color or monochromatic 3-D magnified image of an instrument cluster, at least a portion of the 3-D image being located at a viewing distance greater than the actual optical distance between the dashboard and the driver's eyes. A non-pupil forming display system uses an off-axis aspherical narrow-band reflecting mirror with power to create a magnified virtual image of a miniaturized passive image source, such as a segmented LCD panel, which is backlighted by a small filament incandescent light bulb. A single mirror produces a single monochromatic virtual image, whereas a plurality of stacked and differently curved mirrors, each tuned to different wavelength bandwidth, produces a plurality of spatially separated virtual images of differing colors. The mirrors are holographic optical elements or graded index optical elements.

Abstract: A virtual image display optical system. The system includes an image source, a combiner, and a relay group. The relay group is a catatrioptic relay group that includes a reflective optical element, and a refractive lens group that includes at least one doublet and a diffractive lens. For some applications, the catatrioptric relay group may be replaced by a hybrid refractive-diffractive relay group, thus eliminating the reflective element. The diffractive optical element of the hybrid optical element is encoded on one side of a lens. The hybrid optical element forms a refractive/diffractive achromat to provide for primary chromatic aberration correction. The refractive lens group is also an achromat to provide for chromatic aberration correction. Power distribution between the hybrid optical element and the refractive lens group is such that secondary chromatic aberration of the refractive lens group is balanced out by the secondary chromatic aberration of the hybrid optical element.

Abstract: A focusable virtual image display system employing a focusable image source such as a cathode ray tube and imaging optics to provide a virtual image. The virtual image is viewable by a user and its effective range may be changed without changing the apparent field of view or resolution. By placing the focus point of the imaging optics at the design eye, the image source is moved backwards and forwards, thus effectively changing the range of the virtual image observed by the user without changing the apparent field of view or resolution. The present invention allows the user to adjust the focus position of the virtual image of the image source by moving it relative to the imaging optics, while maintaining the size and resolution of the image. If the user wants to move the image further away, when the image source is moved, the imaging optics moves the virtual image further away and magnifies the image such that the angular field of view stays the same.

Abstract: A focusable virtual image display system employing a focusable image source such as a cathode ray tube and imaging optics to provide a virtual image. The virtual image is viewable by a user and its effective range may be changed without changing the apparent field of view or resolution. By placing the focus point of the imaging optics at the design eye, the image source is moved backwards and forwards, thus effectively changing the range of the virtual image observed by the user without changing the apparent field of view or resolution. The present invention allows the user to adjust the focus position of the virtual image of the image source by moving it relative to the imaging optics, while maintaining the size and resolution of the image. If the user wants to move the image further away, when the image source is moved, the imaging optics moves the virtual image further away and magnifies the image such that the angular field of view stays the same.

Abstract: A compact, inexpensive and mass-producible optical display system for an automobile creates a highly visible and sharp, high contrast and pleasing, multi-color magnified virtual image of a primary instrument cluster at a viewing distance which is greater than the actual optical distance between the dashboard and the driver's eyes in order to enhance instrument readability, minimize driver eye strain, and reduce eye focus problems which are associated with transitioning between the far range viewing used for watching the road ahead and the near range viewing used for glancing at the instruments. A non-pupil forming display system uses a single off-axis aspherical mirror with power to create a virtual image of a miniaturized, multi-color passive image source, such as a segmented LCD panel, which is backlighted by a small filament incandescent light bulb. The aspheric surface is optimized to minimize aberrations and reduce vertical disparity and field curvature.

Abstract: A helicopter sight system including an illuminated reticle for controllably providing reticle imaging illumination and an active display for controllably providing active display illumination that contains alignment information provided by an electronic aiming system, the active display and the reticle being controlled to provide respective imaging illumination at different times. The reticle illumination and the active display illumination are directed by a color beam combiner along a common axis to a focussing lens system which illuminates a transparent combiner to produce a reticle image and an active display image viewable by the operator of the helicopter.

Abstract: A virtual image display for vehicles that includes a first image source for providing first imaging illumination, a second image source for providing second imaging illumination, a combiner responsive to the first and second imaging illumination for producing a combiner imaging illumination output, a negative power aspheric off-axis mirror responsive to the combiner imaging illumination output for providing diverging reflected imaging illumination, and a positive power aspheric off-axis mirror responsive to the diverging imaging illumination for providing converging reflected imaging illumination that produces a virtual image of the image source observable by the vehicle operator. By way of illustrative example, the first image source includes electromechanical gauges, and the second image source includes an alphanumeric display such as a liquid crystal display or a vacuum fluorescent display.

Abstract: A filter device 10 and method of making the same is disclosed. The device comprises holographic means 12 for diffracting optical radiation of a first predetermined range of wavelengths, and optical radiation filter means 14 for filtering optical radiation of a second predetermined range of wavelengths. The optical radiation filter means is coupled with the holographic means.

Abstract: A head-up display having an image source for producing imaging illumination, an optical combiner for partially reflecting the imaging illumination to produce a virtual image of the image source that is viewable by the operator of the vehicle, and a polarizer which can be controllably interposed between the image source and the optical combiner for nighttime use. The polarizer tends to block the illumination that otherwise would produce objectionable ghost images.

Abstract: A head-up instrument display for a vehicle including a light emitting image source for producing imaging illumination and a combiner including a spherical beam-splitter coating for partially reflecting the imaging illumination to produce a virtual image viewable by the vehicle operator without diverting attention from the outside scene. In one embodiment, the head-up instrument display is self-contained with the combiner being rotatable into a stowed position when not in use.

Abstract: A plurality of reflective diffusing holographic memory elements (16) is positioned on a memory plate (14). An array (24) of detectors (22) faces at least one of the memory elements. A laser (26) illuminates the selected memory element and the data stored therein is reflected onto the array for reading. A new memory element may be illuminated or may be brought into interrogation position.

Abstract: A vehicle head-up instrument display including a light emitting image source for producing imaging illumination, optical apparatus for directing the imaging illumination to the inside surface of a vehicle windshield, and a combiner comprising a portion of the windshield or a coating applied to the windshield partially reflects the imaging illumination to produce a virtual image viewable by the driver. The image source and optical apparatus are enclosed in a housing having an elliptical cylindrical transparent cover for transmitting the imaging illumination to the windshield and for directing sunlight and skylight reflections therefrom away from the driver's eyes.

Abstract: An improved optical combiner useful in many applications is disclosed. The combiner includes a substrate with at least one aspheric surface and an diffraction-type reflective coating formed on the substrate for selectively reflecting radiation within one or more predetermined narrow band ranges of wavelengths impinging on the coating. The aspericity of the surface may be selected to compensate or balance optical aberations. The coating is advantageously a graded-index coating, which eliminates the possible degradation of gelatin halogram coatings due to moisture. A process for applying the graded-index coating to a substrate is disclosed. The variation in the index profile of the coating can be selected to provide the capability of combiners with multiple color reflectivity responses, or which allow use of display light sources of wider spectral bandwidth, resulting in a brighter image and improved angular bandwidth.

Abstract: A holographic reflector for reflecting laser radiation at a predetermined wavelength. The reflector employs a plurality of holograms which are disposed adjacent to one another and which are conterminous with each other. The holograms are generally disposed in a support structure which may be a visor or goggle arrangement. Each of the holograms may be either parallel fringe holograms or slanted fringe holograms. The angular orientation of the fringes and the relative spacing thereof determine the angular coverage provided by the reflector. The reflector provides for reflection of laser radiation at a predetermined wavelength and within a particular angular subtence while allowing high see-through in the visible wavelength region. Multiple sets of holograms may also be stacked in order to protect against multiple laser sources.

Abstract: A diffusing screen (50, 50', 50", 102) of a transmission hologram (54, 80, 94, 112) located adjacent to a diffraction optics directional diffusing screen (52, 86, 92, 114) supresses zero-order light from the diffusing screen thereby providing a device having the advantages of a directional diffusing screen but which does not have the disadvantages associated with zero-order light.

Abstract: Optical assembly (34) has a transmission holographic optical element (46) which refracts the incoming ray (38) at an angle through the angularly oriented fiber (56) in fiber optic faceplate (48). Holographic optical element (50) refracts the ray (66) to become ray (44) toward a viewing pupil. The zero-order light from holographic optical element (46) is absorbed as ray (68) in the fiber optic faceplate. The zero-order light represented by ray (76) is absorbed in the holographic optical element (50). Holographic optical element (50) preferably forms a diffused viewing pupil for inspection of the light by the user.

Abstract: A process for depositing on the surface of a substrate a layer of a chosen material having continuous gradations in refractive index in a predetermined periodic pattern. The substrate is exposed to two vapor phase reactants which react upon radiation-inducement to produce the chosen material, and the relative proportion of the reactants is varied in a predetermined and continuous sequence to produce continuous gradations in the stoichiometric composition and refractive index of the deposited layer as a function of thickness. Additionally, predetermined changes in refractive index and/or thickness across the horizontal surface of the substrate may be produced in combination with the change in refractive index as a function of thickness. Diffraction optical elements formed by such a process include various optical filters and reflective optical coatings.

Abstract: A composition comprising a photopolymerizable epoxy-containing material which is useful to provide a hermetically sealed liquid crystal display cell. The photocured seal is chemically resistant to the contents of the liquid crystal cell. Adhesion of the photopolymerizable epoxy material to the glass plates of the liquid crystal cell is improved by addition of glycidoxypropyl triethoxy silane or its precondensate.