LIQUID CRYSTAL DEVICES

• US 3,787,110 A
• Filed: 06/23/1972
• Issued: 01/22/1974
• Est. Priority Date: 06/23/1972
• Status: Expired due to Term

• Current Assignee: Donald Lawrence White, Dwight Winton Berreman, Frederic Jay Kahn, Saul Meiboom
• Original Assignee: Donald Lawrence White, Dwight Winton Berreman, Frederic Jay Kahn, Saul Meiboom
• Inventors: White, Donald Lawrence, Kahn, Frederic Jay, Berreman, Dwight Winton, Meiboom, Saul
• Primary Examiner(s): Bauer, Edward S.
• Application Number:
  US05/265,459
• Time in Patent Office: 578 Days
• Field of Search: 350/16LC,150
• US Class Current: 349/123
• CPC Class Codes: G02F 1/133765 without a surface treatment
• CPC Class Codes: G02F 1/13378 by treatment of the surface, e.g. embossing, rubbing or light irradiation G02F1/133711, G02F1/133734, G02F1/133753 take precedence

Abstract

Liquid crystal devices, an operation state of which is dependent upon substantially unidirectional liquid crystal orientation, includes a contacting surface which has parallel grooves or ridges. Liquid crystal orientation is attributed to minimization of elastic energy.

Claims

2. Device of claim 1 in which the said interface is substantially free of non-liquid crystalline molecules of a greatest dimension as long as that of the greatest dimension of the molecules of the liquid crystalline material.

3. Device of claim 1 together with means for altering the alignment of at least a portion of the said liquid crystalline material.

4. Device of claim 3 in which the same means includes at least one conductive electrode having a major face substantially parallel to the said interface.

5. Device of claim 4 in which the said means includes two conductive electrodes which straddle at least a portion of the said liquid crystalline material.

6. Device of claim 5 in which the said electrodes are in intimate contact with the said liquid crystalline material.

7. Device of claim 6 in which there is a layer of additional material intermediate at least one of the said electrodes and the said liquid crystalline material which affects the wetting angle of the said liquid crystalline material.

8. Device of claim 7 in which the said additional layer is a surfactant which causes the said liquid crystalline material to align parallel to the said interface.

9. Device of claim 4 in which the said change in alignment results in a second aligned state.

10. Device of claim 9 in which the said second aligned state is essentially orthoganal to the said interface.

11. Device of claim 9 in which the second aligned state is parallel to the said interface.

12. Device of claim 3 in which there are two layers of non-liquid crystalline material both in intimate contact with the said layer of liquid crystalline material.

13. Device of claim 4 in which the surfaces of both of the said layers of non-liquid crystalline material contain elevational variations as described and in which the interface is formed between the said liquid crystalline material and the two layers of non-liquid crystalline material are substantially parallel.

14. Device of claim 13 in which the elevational variations of the two said surfaces are substantially parallel.

15. Device of claim 14 including at least one element which is selectively transmissive for one sense of plane polarized light.

16. Device of claim 13 in which the said elevational variations of the said two non-liquid crystalline layers are essentially non-parallel.

17. Device of claim 16 in which the said elevational variations are essentially orthoganal.

18. Device of claim 17 including at least one additional element which is selectively transmissive for one sense of plane polarized light.

19. Device of claim 3 in which the said means includes means for changing temperature of the said liquid crystalline material.

20. Device of claim 19 in which the second state is essentially disaligned.

21. Device of claim 1 in which the layer consisting essentially of the said liquid crystalline includes a chemical species which is light-absorbent which is composed of elongated molecules and in which their major axes are aligned substantially with the major axes of the molecules of the said liquid crystalline material.