Liquid crystal display with split electrode

• US 20100045180A1
• Filed: 08/19/2008
• Published: 02/25/2010
• Est. Priority Date: 08/19/2008
• Status: Active Grant

• Current Assignee: World Properties Incorporated
• Original Assignee: World Properties Incorporated
• Inventors: Kimball, Robert Allen, Seelhammer, Mark A., Pires, David G.
• Granted Patent: US 7,876,399 B2
• Time in Patent Office: Days
• US Class Current: 313/509
• CPC Class Codes: C09K 2323/00 Functional layers of liquid crystal optical display excluding electroactive liquid crystal layer characterised by chemical composition
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/134309 characterised by their geometrical arrangement
• CPC Class Codes: G02F 1/134354 the sub-pixels being capacitively coupled
• CPC Class Codes: G02F 2201/44 Arrangements combining different electro-active layers, e.g. electrochromic, liquid crystal or electroluminescent layers

Abstract

A light shutter includes a first electrode, a second electrode, and a third electrode, wherein the first and second electrodes are capacitively coupled to each other by the third electrode. The first electrode and the second electrode can be segmented and the segments separately addressed. In a display having a light shutter and an EL panel stacked on the same side of a substrate, there is a common front electrode and separate rear electrodes for operating the light shutter and the EL panel. The common electrode is electrically floating and the rear electrodes are capacitively coupled to each other by the common front electrode. The rear electrodes can be segmented and the segments separately addressed.

Claims

1. A light shutter including a layer of polymer dispersed liquid crystal material characterized in that the shutter includes a first electrode, a second electrode, and a third electrode, wherein the first and second electrodes are capacitively coupled to each other by the third electrode.

2. The light shutter as set forth in claim 1 wherein said first electrode and said second electrode are on a first side of said layer and the third electrode is on a second side of the layer, opposite the first electrode and the second electrode.

3. The light shutter as set forth in claim 2 wherein the first electrode and the second electrode are coupled to a source of voltage and said third electrode is electrically floating.

4. The light shutter as set forth in claim 2 and further including a fourth electrode on said first side of said layer, said fourth electrode being selectively coupled to one of the first electrode and the second electrode.

5. A display including a transparent substrate, a light shutter overlying the substrate and an EL layer overlying the light shutter characterized in that the display has a common front electrode, a first rear electrode between the light shutter and the EL layer, and a second rear electrode overlying the EL layer.

6. The display as set forth in claim 5 wherein said common front electrode is floating electrically.

7. The display as set forth in claim 6 wherein the first rear electrode and the second rear electrode are coupled to a source of voltage and capacitively coupled to said common front electrode.

8. The display as set forth in claim 5 wherein the second rear electrode has plural segments.

9. The display as set forth in claim 8 wherein the segments are separately addressable.

10. The display as set forth in claim 5 wherein the first rear electrode has plural segments.

11. The display as set forth in claim 10 wherein the segments are separately addressable.

12. The display as set forth in claim 5 wherein both rear electrodes each have plural segments.

13. The display as set forth in claim 12 wherein the plural segments are separately addressable.

14. The display as set forth in claim 13 wherein selecting a particular combination of segments causes a first region of the EL layer to emit light and a corresponding region of the light shutter to be opaque, thereby blocking the light from the first region.

15. The display as set forth in claim 14 wherein selecting said particular combination of segments causes a second EL lamp to increase in brightness and a second light shutter to be transparent.

16. The display as set forth in claim 5 wherein the EL panel includes an EL lamp having a patterned layer of phosphor.

17. A display including a transparent substrate, a light shutter overlying the substrate and an EL panel overlying the light shutter characterized in that the display includes a first electrode, a second electrode, and a third electrode, wherein the first electrode controls the light shutter, the second electrode controls the EL panel, and the third electrode is electrically floating, wherein the first and second electrodes are capacitively coupled to each other by the third electrode.

18. The display as set forth in claim 17 wherein said third electrode overlies said transparent substrate and the light shutter overlies said third electrode.