Simulation display system

• US 5,566,370 A
• Filed: 11/03/1994
• Issued: 10/15/1996
• Est. Priority Date: 11/03/1994
• Status: Expired due to Term

• Current Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Original Assignee: Lockheed Martin Corporation (Martin Marietta Corporation)
• Inventors: Young, C. Gilbert
• Primary Examiner(s): Chin, Tommy P.
• Assistant Examiner(s): Le, Vu
• Application Number:
  US08/334,265
• Time in Patent Office: 712 Days
• Field of Search: 348/36,39, 348/42, 348/51-56, 348/115, 348/121, 348/123, 348/124, 348/776, 348/778, 348/779, 359/631-633, 359/453-459
• US Class Current: 348/36
• CPC Class Codes: G09B 9/05 the view from a vehicle being simulated G09B9/052, G09B9/058 take precedence
• CPC Class Codes: G09B 9/32 by projected image G09B9/307, G09B9/36 take precedence
• CPC Class Codes: H04N 7/18 Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast

Abstract

A compact display system simulates a panoramic view to an observer located at a central viewing station. A toric mirror, comprising a compressed portion of a sphere, has a concave reflective surface disposed in surrounding relation to the given viewing station while a spherical rear projection screen which receives projected image light on its inner surface presents a panoramic image to the toric mirror from its outer surface. A plurality of projectors are disposed tangentially above the upper periphery of the rear projection screen and project associated portions of the light image onto the inside of the screen via fold mirrors. Each projector includes a high intensity CRT and a color shutter.

Claims

1. An apparatus for presenting a panoramic scene about a viewing station comprising:

plural projectors, each projector providing light representative of a given portion of said panoramic scene;

a reflector for each projector that provides an indirect optical path for the propagation of projected light;

an intermediate rear-projection screen receiving the projected light from the plural projectors via the associated reflectors and providing a continuous panoramic object scene in accordance with the projected light received; and

a reflector that forms an enlarged virtual image of said continuous panoramic object scene, said reflector directing the light rays of said continuous panoramic object scene such that said enlarged virtual image appears to be located at a distance from the viewing station substantially greater than that of the direct optical path.

2. An apparatus according to claim 1 wherein each projector of said plural projectors comprises:

a high intensity CRT forming an image on a screen thereof; and

a lens assembly that optically projects the CRT image toward the projector'"'"'s associated reflector;

each said projector having an initial propagation direction that is substantially parallel to the longitudinal axis of its associated CRT, wherein the reflector associated with each projector redirects the propagation direction by a reflection angle of between 70°

to 110°

.

3. An apparatus according to claim 2 wherein each projector of said plural projectors further comprises a color switch disposed in the optical path of the projected image.

4. An apparatus according to claim 3 wherein said color switch includes three selectable color states and passes light of a respective one of three colors in accordance with the color state selected, said apparatus further comprising:

drive circuitry for sequentially driving said CRT with separate luminance image information of said three colors so that said CRT screen is separately and sequentially illuminated with the separate luminance image information of said three colors; and

a color switch controller for selecting color states of said color switch in accordance with the respective luminance image information of said three colors on the CRT screen.

5. An apparatus according to claim 4 wherein said drive circuitry includes:

R, G and B frame buffers for providing the respective luminance image information as associated with red, green and blue color components of an image frame; and

multiplexing circuitry for sequentially coupling said CRT to the respective R, G and B frame buffers for receiving the respective luminance image information thereof, said R, G and B frame buffers being selected in synchronization with the selection of associated color states of said color switch.

6. An apparatus according to claim 1 wherein the intermediate imager comprises a rear projection screen that receives said projected light on one surface thereof and portrays the continuous panoramic object scene on the opposite surface.

7. An apparatus according to claim 6 wherein the rear projection screen has a spherical contour shape of a given circumference and is translucent, said projected light as redirected by said associated reflectors being received upon the rear projection screen'"'"'s inner surface and portraying said continuous panoramic object scene from its outer surface, each reflector redirecting the projected light of the associated projector with the longitudinal length of each projector being oriented in substantially tangential relationship to the periphery of the rear projection screen.

8. An apparatus for presenting a panoramic view, said apparatus having a vertical central axis, said apparatus comprising:

a toric mirror having a cross section of an arc of a circle in the vertical plane of said apparatus'"'"' central axis, the radius of said circle is greater than half the diameter of said toric mirror;

a rear projection screen for receiving projected image light upon its inner surface and presenting a panoramic object image to the toric mirror from its outer surface, said rear projection screen comprising a segment of a sphere having a radius of curvature originating at said central axis; and

a plurality of projectors that provide said projected image light, each projector providing image light for an associated portion of said panoramic object image.

9. An apparatus according to claim 8 wherein the rear projection screen presents the panoramic object image to the toric mirror at a proximity closer to the concave reflective surface of the toric mirror than the focal distance thereof so that a magnified virtual image of the object image optically appears at a substantial distance beyond the reflective surface of said toric mirror.

10. An apparatus according to claim 8 wherein the rear projection screen has a spherical, concave outer surface of a radius less than the larger of the two radii of curvature of the concave reflective surface of the toric mirror.

11. An apparatus according to claim 10 wherein the rear projection screen has a radius of curvature from said central axis which is disposed in vertically offset relation above the center of the toric mirror for providing a panoramic object scene for the toric mirror similarly above the toric mirror so that a virtual image is viewable along an optical path beneath and without interference from the rear projection screen.

12. An apparatus according to claim 10 wherein the plurality of projectors project image light of respective portions of said panoramic object image, with each associated portion matching contiguously with neighboring portions thereof such that said panoramic object image is substantially continuous.

13. An apparatus according to claim 10 wherein each projector includes:

a high intensity CRT having a screen providing a CRT image corresponding to its associated portion of the panoramic object image; and

projection optics for focusing rays of light of the CRT image and projecting image light thereof along an optical path toward an allocated area of the rear projection screen, said allocated area of the rear projection screen being contiguously related to neighboring allocated areas of the rear projection screen that are to receive projected image light from others of the plurality of projectors.

14. An apparatus according to claim 13 wherein each projector includes a color switch disposed in the optical path of projected image light, the color switch having selectable states for passing respective colors of light.

15. An apparatus according to claim 13 wherein each projector is proximate a position disposed above the rear projection screen and opposite, across a diameter of, the rear projection screen.

16. An apparatus according to claim 15 wherein each projector includes a reflector for directing the projector'"'"'s associate image light down and across the diameter of the rear projector screen onto the allocated area of the rear projection screen.

17. An apparatus according to claim 16 wherein each said reflector provides a folded optical path for propagating said image light from the respective CRT, the CRT and projection optics having an optical projection axis oriented above and in primarily tangential relationship to an upper periphery of the rear projection screen.