Segmented polymer stabilized and polymer free cholesteric texture liquid crystal displays and driving method for same

• US 5,636,044 A
• Filed: 10/14/1994
• Issued: 06/03/1997
• Est. Priority Date: 10/14/1994
• Status: Expired due to Term

• Current Assignee: Kent Displays Incorporated
• Original Assignee: Kent Displays Incorporated
• Inventors: Ventouris, George, Yuan, Haiji
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): NGUYEN, TIEP HUU
• Application Number:
  US08/321,848
• Time in Patent Office: 963 Days
• Field of Search: 359/89, 359/88, 359/87
• US Class Current: 349/142
• CPC Class Codes: G02F 1/134327 Segmented, e.g. alpha numeric display
• CPC Class Codes: G02F 1/13718 based on a change of the texture state of a cholesteric liquid crystal

Abstract

A display device (110) having first and second substrates (112) and (190) and a layer of a liquid crystal material having a periodic modulated structure, such as a PSCT or PFCT liquid crystal material disposed therebetween. The first substrate is divided into segment and non-segmented areas which are defined by a gap in the electrode materials disposed on the substrate. Similarly, the second substrate (190) is divided into common electrodes corresponding to the segmented and non-segmented areas on the first substrate.

Claims

1. A segmented liquid crystal display for a periodic modulated optical structure liquid crystal material, said display comprising:

a first display substrate having a layer of patterned conductive material disposed thereon, said patterned conductive material forming a plurality of display segments, and connecting regions in an active zone of said substrate, a plurality of peripheral regions in a background zone of said substrate, and a plurality of contact pads;

wherein said display segments comprise at least part of an image to be presented on said display, and wherein said contact pads provide for electrical communication with display driving circuitry;

a second display substrate having a conductive material disposed thereon, said conductive material forming a conductive display region, and a conductive background region wherein said conductive display region and said conductive background region are electrically isolated by a thin and continuous region forming a gap; and

a layer of periodic modulated optical structure liquid crystal material disposed between said first and second substrates.

2. A display as in claim 1, wherein said conductive display region on said second substrate forms a pattern corresponding to said display segments on said first substrate.

3. A display as in claim 1, wherein said contact pads effect electrical communication between electronic driving circuitry and said active region and said conductive background region on said second substrate.

4. A display as in claim 1, wherein said contact pads effect electrical communication between electronic driving circuitry and said display segments.

5. A display as in claim 4, wherein said contact pads are connected to said segments via said connecting regions.

6. A display as in claim 1, wherein said patterned conductive material on said first display substrate and said conductive material on said second display substrate is a transparent conductive material.

7. A display as in claim 6, wherein said transparent conductive material is indium tin oxide.

8. A display as in claim 6, wherein said patterned layers of conductive material are provided by selectively removing preselected areas of said conductive material.

9. A display as in claim 1, wherein said liquid crystal material is a cholesteric texture liquid crystal material.

10. A display as in claim 1, wherein said liquid crystal material is a cholesteric texture liquid crystal material selected from the group consisting of polymer free and polymer stabilized cholesteric texture liquid crystal materials.

11. A display as in claim 1, wherein said segmented display is adapted to display at least one digit.

12. A display as in claim 11, wherein each said digit comprises seven display segments.

13. A display as in claim 1, wherein said display substrates are fabricated of a material selected from the group consisting of glass, plastic, quartz, polymeric materials, and combinations thereof.

14. A segmented liquid crystal display for a periodic modulated optical structure liquid crystal material, said display comprising:

a first display substrate having a layer of patterned conductive material disposed thereon, said patterned conductive material defining a plurality of display segments and connecting regions in an active zone of said substrate wherein each display segment and connecting region is electrically isolated from its adjacent display segments and connecting regions by a thin and continuous region forming a gap, a plurality of peripheral regions in a background zone of said substrate, and a plurality of contact pads, wherein said display segments comprise at least part of an image to be presented on said display, and wherein said contact pads provide for electrical communication with display driving circuitry;

a second display substrate having a conductive material disposed thereon, said conductive material defining a conductive display region, and a conductive background region wherein said conductive display region and said conductive background region are electrically isolated by a thin and continuous region forming a gap; and

a layer of periodic modulated optical structure liquid crystal material disposed between said first and second substrates.

15. A display as in claim 14, wherein said conductive display region on said second substrate forms a pattern corresponding to said display segments on said first substrate.

16. A display as in claim 14, wherein said contact pads effect electrical communication between electronic driving circuitry and said active region and said conductive background region on said second substrate.

17. A display as in claim 14, wherein said contact pads effect electrical communication between electronic driving circuitry and said display segments.

18. A display as in claim 17, wherein said contact pads are connected to said segments via said connecting regions.

19. A display as in claim 14, wherein said patterned conductive material on said first display substrate and said conductive material on said second display substrate is a transparent conductive material.

20. A display as in claim 19, wherein said transparent conductive material is indium tin oxide.

21. A display as in claim 19, wherein said patterned layers of conductive material are provided by selectively removing preselected areas of said conductive material.

22. A display as in claim 14, wherein said liquid crystal material is a cholesteric texture liquid crystal material.

23. A display as in claim 14, wherein said liquid crystal material is a cholesteric texture liquid crystal material selected from the group consisting of polymer free and polymer stabilized cholesteric texture liquid crystal materials.

24. A display as in claim 14, wherein said segmented display is adapted to display at least one digit.

25. A display as in claim 24, wherein each said digit comprises seven display segments.

26. A display as in claim 14, wherein said display substrates are fabricated of a material selected from the group consisting of glass, plastic, quartz, polymeric materials, and combinations thereof.