Liquid crystal light valve goggles for eye protection

• US 5,081,542 A
• Filed: 12/12/1989
• Issued: 01/14/1992
• Est. Priority Date: 12/12/1989
• Status: Expired due to Term

• Current Assignee: Hughes Electronics Corporation (Rtx Corporation)
• Original Assignee: Hughes Aircraft Company (Rtx Corporation)
• Inventors: Schoenmakers, Wayne, Wu, Shin-Tson, Hsu, Tsung-Yuan, Efron, Uzi
• Primary Examiner(s): Miller, Stanley D.
• Assistant Examiner(s): GROSS, ANITA P
• Application Number:
  US07/450,118
• Time in Patent Office: 763 Days
• Field of Search: 350/331 R, 350/338, 350/342, 2/426, 340/705
• US Class Current: 349/11
• CPC Class Codes: A61F 9/023 with variable transmission, e.g. photochromic for welding A61F9/067
• CPC Class Codes: A61F 9/067 with variable transmission
• CPC Class Codes: G02F 1/1352 Light-reflecting layers
• CPC Class Codes: G02F 1/1354 having a particular photoconducting structure or material

Abstract

An eye protection device 10 comprising a liquid crystal light valve 20 for providing an image of a scene. The light valve images the field of view under observation in a spectral range which matches the human eye. It will automatically reject a laser threat by simply absorbing the energy therefrom in the photoconductive layer thereof. Thus, the invention 10 provides a broad spectrum, zero response time, angle and polarization independent, sensitive eye protection device having a fast recovery time, high extinction coefficient and a high damage threshold. Hence, the invention is expected to be of significant utility to personnel operating in hostile environments.

Claims

1. An eye protection device comprising:

a liquid crystal light valve for providing an image of a scene in a spectral range suitable for human viewing and for preventing harmful radiation from being transmitted for viewing, wherein said liquid crystal light valve includes a photoconductive layer, and

means for supporting the light valve to facilitate the viewing thereof.

2. The invention of claim 1 wherein said photoconductive layer comprises silicon.

3. The invention of claim 2 wherein the silicon is single crystalline silicon.

4. The invention of claim 1 wherein the photoconductive layer comprises lead salts.

5. The invention of claim 1 including an objective lens mounted along the optical train of said light valve.

6. The invention of claim 5 including an eyepiece lens mounted along the optical axis of said light valve.

7. The invention of claim 1 including light emitting diode means for reading said light valve.

8. The invention of claim 1 including reflector means for reflecting said image to the eye of a viewer.

9. An eye protection device comprising:

a liquid crystal light valve for providing an image of a scene;

means for supporting the light valve to facilitate the viewing thereof;

reflector means for reflecting said image to the eye of a viewer; and

means for moving said reflecting means from a first position to a second position.

10. An eye protection device comprising:

a liquid crystal light valve for providing an image of a scene;

means for supporting the light valve to facilitate the viewing thereof;

reflector means for reflecting said image to the eye of a viewer; and

folding mirror means for folding the optical train of said device.

11. The invention of claim 10 including relay lens disposed in the optical train of said light valve.

12. An eye protection device comprising:

a liquid crystal light valve for providing an image of a scene;

means for supporting the light valve to facilitate the viewing thereof, and

means for inverting the image provided by said light valve.

13. The invention of claim 12 including twisting fiber mounted in the optical train of said light valve.

14. An eye protection device comprising:

a liquid crystal light valve for providing an image of a scene; and

means for supporting the light valve to facilitate the viewing thereof, wherein said means for supporting the light valve includes counter weights mounted on a helmet on which said device is installed.

15. Eye protection goggles comprising:

two reflective liquid crystal light valves for providing an image of a scene;

an objective lens for, one for each light valve, mounted along the optical train thereof;

an eyepiece lens, one for each light valve, mounted along the optical axis thereof; and

means for supporting the light valves to facilitate the viewing thereof.

16. The invention of claim 15 including light emitting diode means for reading said light valves.

17. The invention of claim 15 including reflector means for reflecting said image to the eye of a viewer.

18. The invention of claim 17 including means for moving said reflecting means from a first position to a second position.

19. The invention of claim 17 including folding mirror means for folding the optical train of said device.

20. The invention of claim 19 including relay lens disposed in the optical train of said light valves.

21. The invention of claim 15 including means for inverting the image provided by said light valves.

22. The invention of claim 21 including twisting fiber mounted in the optical train of said light valves.

23. The invention of claim 15 wherein said means for supporting the light valves includes counter weights mounted on a helmet on which said device is installed.

24. A target locator system comprising:

liquid crystal light valve goggles for imaging a scene in a spectral range suitable for human viewing, wherein said liquid crystal light valve includes a photoconductive layer, and

a head-up display.

25. An eye protection device comprising:

at least one liquid crystal light valve goggle for imaging a scene; and

a helmet to which said at least one liquid crystal light valve goggle is pivotally attached,

said liquid crystal light valve goggle including;

a photoconductive layer for receiving input images;

means on said photoconductive layer for blocking threat radiation, and

a layer comprising liquid crystal for modulating a readout light and replicating the input images for viewing in response to the input images received by said photoconductive layer.

26. The eye protection device of claim 25 further including:

a light emitting diode mounted for optical illumination of the viewing surface of said light valve.

27. The eye protection device of claim 25 wherein said liquid crystal light valve further includes heating electrodes.

28. The eye protection device of claim 25 wherein said goggle further includes a polarizing beam splitter having a holographic lens fabricated thereon.

29. The eye protection device of claim 25 wherein said means for blocking threat radiation includes:

metal matrix mirror having pixels and channels between said pixels, and

a reflective layer covering both said pixels and said channels.