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 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 virtual image display (VID) optical system that is very compact and has a wide field of view. The present optical system has good image quality, has simple optics, is very compact, provides wide field coverage, and has very large field overlaying. The system comprises a combiner and a catadioptric relay group disposed along an optical path between a cathode ray tube and an operator. The virtual image display system of the present invention is adapted to enlarge an image of the cathode ray tube viewed by the operator. The catadioptric relay group is typically comprised of a concave mirror and one refractive sub-group with at least one lens, and provides excellent image quality over a very wide field of view. The concave mirror contributes positive optical power to the system, thus providing for a compact optical system. The concave mirror may be tilted and/or decentered to balance the asymmetric aberrations generated by the combiner.

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 high efficiency x-prism beamsplitter for use in such applications as helmet mounted visor displays. By using polarization-sensitive dielectric coatings arranged along with half-wave plates, the x-prism can theoretically deliver 50% illumination to each eye with no loss. In addition to the higher efficiency, the glare throughput found in conventional x-prisms can be theoretically reduced to zero.

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 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 holographic full-color, data retrieval and projection system includes a holographic information storage plate that includes a plurality of reflective holograms, each designed to diffract light over a certain spectral bandwidth, and a holographic screen character plate, which includes a plurality of screen hologram character shapes that reflect diffracted light in a uniform, well-defined cone of diffuse light directed toward the viewer, producing images having high screen gain and high brightness, yet with lower power consumption than heretofore obtained.

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 optical screen module for full-color, on axis viewing is described. The module has a transmission holographic optical element, a louver filter, and a diffraction optics diffusion screen. Input light is diffracted off-axis by the transmission holographic element, passed through the louver filter and rediffracted on-axis by the diffusion screen. The module can handle full-color light because the dispersion in the transmission hologram is compensated by that in the diffusion screen. The louver filter blocks the undiffracted zero-order light while allowing the light diffracted by the transmission hologram to pass through.

Abstract: A radiused fiber optic faceplate is disclosed, particularly suited for use in optical apparatus comprising a high gain diffusion screen or a direct view CRT. The respective optical axis of the fibers are each substantially oriented so that the refracted information-bearing light passed through each fiber is directed to the exit pupil and ambient light from outside the exit pupil is absorbed in the faceplate. The faceplate therefore substantially increases the contrast enhancement.