Shatter-proof liquid crystal panel with infrared filtering properties

• US 4,749,261 A
• Filed: 12/30/1986
• Issued: 06/07/1988
• Est. Priority Date: 01/17/1986
• Status: Expired due to Term

• Current Assignee: Raychem Limited (TE Connectivity Limited)
• Original Assignee: Taliq Corp. (Raychem Corporation)
• Inventors: Drzaic, Paul, Marsland, Steven, McLaughlin, Charles W.
• Primary Examiner(s): Miller, Stanley D.
• Assistant Examiner(s): Gallivan, Richard
• Application Number:
  US06/947,793
• Time in Patent Office: 525 Days
• Field of Search: 350/339 R, 350/339 F, 350/347 V, 350/347 R, 350/334, 350/331 R
• US Class Current: 349/16
• CPC Class Codes: B32B 17/10018 comprising only one glass sheet
• CPC Class Codes: B32B 17/10302 Edge sealing
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: B60J 3/04 adjustable in transparency
• CPC Class Codes: E06B 2009/2464 featuring transparency control by applying voltage, e.g. LCD, electrochromic panels
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/13725 based on guest-host interaction G02F1/13762, G02F1/13737, take precedence

Abstract

Liquid crystal material is operable to modulate light transmitted through a panel such as a sunroof, window or partition. The panel may have safety glazing properties. The panel may also include means for reflecting infrared energy. The liquid crystal material includes operationally nematic liquid crystal having positive dielectric anisotropy and a containment medium for containing plural volumes of the liquid crystal material. The panel includes transparent surfaces with the liquid crystal material disposed therebetween and selectively operable primarily to transmit or primarily to scatter light. The liquid crystal material may alternatively include volumes of liquid crystal with a pleochroic dye in a containment medium for selectively attenuating light.

Claims

1. A liquid crystal panel, comprising:

first and second transparent surfaces through which visible light incident thereon may be transmitted;

liquid crystal means located between said transparent surfaces for determining the amount of light transmitted through said panel;

said liquid crystal means including operationally nematic liquid crystal having positive dielectric anisotropy and a containment medium means for containing plural volumes of said liquid crystal; and

means for reducing the amount of infrared energy transmitted through said panel.

2. The panel of claim 1 further including means for absorbing ultraviolet radiation incident thereon.

3. The panel of claim 1 further including a polarizer for absorbing the polarization incorporating the light scattered by said liquid crystal means in a field-on state.

4. The panel of claim 1 further including a depolarizer for altering the polarization of light prior to incidence on said liquid crystal means.

5. The panel of claim 1 wherein said first and second transparent surfaces have anti-abrasive properties.

6. The panel of claim 1 wherein at least one of said surfaces has anti-lacerative or shatter-resistant properties.

15. The panel of claim 1 or 10 wherein said first transparent surface is an outer surface that is formed of glass that includes said infrared energy reducing means.

16. The panel of claim 15 wherein said second transparent surface is an inner surface that has anti-lacerative or shatter-resistant properties.

17. The panel of claims 1, 8 or 10 wherein said infrared energy reducing means comprises an infrared energy absorbing dye in said liquid crystal material.

18. The panel of claims 1, 8 or 10 wherein said infrared energy reducing means comprises a layer for preferentially reflecting infrared light.

23. The panel of claims 1, 7, 10, or 19 wherein one of said transparent surfaces comprises a flexible, scratch-resistant plastic film including an electrically-conductive, optically transparent coating and said liquid crystal means.

24. The panel of claims 1, 7, 10, or 19 wherein said containment medium means comprises surface means for distorting the natural structure of said liquid crystal absent a prescribed input.

25. The panel of claim 24 wherein said liquid crystal is birefringent and has an ordinary index of refraction in the presence of a prescribed input that is substantially matched to the index of refraction of said containment medium means to minimize refraction and scattering of light and an extraordinary index of refraction in the absence of such prescribed input that is different from the index of refraction of said containment medium means to cause refraction and scattering of light.

26. The panel of claim 24 further including input means for applying the prescribed input to said liquid crystal means.

27. The panel of claim 26 wherein said input means comprises electrode means at opposite surfaces of said liquid crystal means for applying an electric field across said liquid crystal means.

28. The panel of claim 27 further including circuit means for providing electric energy to said electrode means to effect application of an electric field to said liquid crystal means.

29. The panel of claim 28 wherein at least one of said transparent surfaces is electrically conductive and comprises at least one of said electrode means.

30. The panel of claim 24 further comprising pleochroic dye in said liquid crystal.

31. The panel of claim 30 wherein the structure of said pleochroic dye conforms to the structure of said liquid crystal, said dye being operative to absorb light when said liquid crystal structure is in distorted alignment.

32. The panel of claim 30 further including means for applying an electric field to said liquid crystal means to tend to effect generally parallel alignment of said liquid crystal structure to reduce the amount of absorption by said dye.

33. The panel of claim 32 wherein said means for applying includes plural electrodes, one on each side of said liquid crystal means.

34. The panel of claim 1, 7, 10, or 19 utilized as a divider between interior portions of a vehicle.

35. The panel of claims 1, 7, 10, or 19 utilized as a sunroof or a moonroof.

36. The panel of claims 1, 7, 10, or 19 utilized as a vehicle window.

37. The panel of claims 1, 7, 10, or 19 utilized as an architectural window.

38. The panel of claims 1, 7, 10, or 19 utilized as a skylight or an interior building partition.

39. The panel of claim 1, 7, 10, or 19 wherein at least one of said transparent surfaces is tinted.

40. The panel of claims 1, 7, 10, or 19 wherein at least one of said transparent surfaces is coated with a material with a high index of refraction.

41. The panel of claims 1, 7, 10, or 19 further including a layer for reflecting visible light.

7. A liquid crystal panel, comprising:

first and second transparent surfaces through which visible light incident thereon may be transmitted;

liquid crystal means located between said transparent surfaces and adhered to at least one of said transparent surfaces for determining the amount of light transmitted through said panel;

said liquid crystal means including operationally nematic liquid crystal having positive dielectric anisotropy and a containment medium means for containing plural volumes of said liquid crystal; and

the combination of said liquid crystal means, and said first and second transparent surfaces providing said panel with safety glazing properties.

8. The panel of claim 7 further including means for reducing the amount of infrared energy transmitted through said panel.

9. The panel of claim 7 further including a depolarizer for altering the polarization of light prior to incidence on said liquid crystal means.

10. A liquid crystal panel, comprising:

first and second transparent surfaces through which visible light incident thereon may be transmitted;

liquid crystal means located between said transparent surfaces for modulating light incident on said panel;

said liquid crystal means including operationally nematic liquid crystal having positive dielectric anisotropy and a containment medium means for containing plural volumes of said liquid crystal;

means for reducing the amount of infrared energy transmitted through said panel; and

said liquid crystal means including a plastic substrate adhered to at least one of said transparent surfaces to provide said panel with safety glazing properties.

11. The panel of claim 10 further including means for absorbing ultraviolet light incident on said panel.

12. The panel of claim 11 further including a light polarizer for absorbing the light polarization incorporating the light scattered by the liquid crystal means in a field-on state to produce a clearer panel in such state.

13. The panel of claims 11 or 12 wherein said first and second transparent surfaces include anti-abrasive properties.

14. The panel of claim 10 further including a light depolarizer for altering the polarization of light prior to incidence on said liquid crystal means to increase the brightness of an image observed through the panel.

19. A liquid crystal panel, comprising:

first and second transparent surfaces through which visible light incident thereon may be transmitted;

liquid crystal means located between said transparent surfaces for modulating light incident on said panel;

said liquid crystal means including operationally nematic liquid crystal having positive dielectric anisotropy and a containment medium means for containing plural volumes of said liquid crystal; and

said liquid crystal means including a plastic substrate means adhered to at least one of said transparent surfaces to provide said panel with safety glazing properties.

20. The panel of claims 7, 8, 9, or 19 wherein said first and second transparent surfaces include anti-abrasive properties.

21. The panel of claims 7, 8, 9, or 19 further including means for absorbing ultraviolet radiation incident thereon.

22. The panel of claims 7, 8, 9, or 19 further including a polarizer for absorbing the polarization incorporating the light scattered by said liquid crystal means in a field-on state.

42. The panel of claim 19 further including means for reducing the amount of infrared energy transmitted through said panel.

43. The panel of claim 19 further including a depolarizer for altering the polarization of light prior to incidence on said liquid crystal means.