Electronically switchable privacy device

Patent metadata

Field	Value
Publication number	US-9500888-B2
Application number	US-201414772246-A
Country	US
Kind code	B2
Filing date	Mar 7, 2014
Priority date	Mar 13, 2013
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

An electronically switchable privacy device suitable for use in display devices is described. The electronically switchable privacy device comprises a first transparent electrode layer, an electronically switchable layer disposed adjacent to the first transparent electrode layer, and a second transparent electrode layer disposed adjacent to the electronically switchable layer and opposite the first transparent electrode layer. The second transparent electrode layer comprises a transparent substrate layer having a plurality of microstructured ribs extending across a major surface of the transparent substrate layer such that the microstructured ribs form an alternating series of ribs and channels, each channel having channel walls defined by adjacent ribs. A plurality of transparent electrode members comprising a transparent electrode material are disposed on at least one channel wall in a corresponding plurality of the channels; and a bus member provides electrical connectivity across the plurality of transparent electrode members. A spacer element disposed in the electronically switchable layer keeps the first transparent electrode layer spaced apart from the second transparent electrode layer. A portion of the electronically switchable layer at least partially fills the plurality of channels and makes electrical contact with the plurality of transparent electrode members. The electronically switchable layer comprises an electronically switchable material capable of modulation between high and low light absorption states upon application of a direct current voltage across the first and second transparent electrode layers.

First claim

What is claimed is:

1. A privacy device that is electronically switchable, comprising:
a first transparent electrode layer comprising:
a first transparent substrate layer and a first transparent electrically conductive layer disposed on a major surface of the first transparent substrate layer, wherein the first transparent substrate layer is flexible;

an electronically switchable layer disposed adjacent to the first transparent electrically conductive layer;
a second transparent electrode layer disposed adjacent to the electronically switchable layer and opposite the first transparent electrically conductive layer, the second transparent electrode layer comprising:
a second transparent substrate layer;
a plurality of microstructured ribs extending across a major surface of the second transparent substrate layer such that the microstructured ribs form an alternating series of ribs and channels, each channel having channel walls defined by adjacent ribs;
a plurality of transparent electrode members comprising a transparent electrode material disposed on at least one channel wall in a corresponding plurality of the channels; and
a bus member providing electrical connectivity across the plurality of second transparent electrode members; and
a spacer element disposed in the electronically switchable layer such that the first transparent electrode layer is spaced apart from the second transparent electrode layer by the spacer element;

wherein a portion of the electronically switchable layer at least partially fills the plurality of channels and makes electrical contact with the plurality of transparent electrode members;
wherein the electronically switchable layer comprises an electronically switchable material capable of modulation between high and low light absorption states upon application of a direct current voltage across the first and second transparent electrode layers; and
wherein:
when a first direct current voltage is applied, the film is in a privacy mode such that it has a light transmission of less than about 10% at viewing angle of 30°;
when a second direct current voltage is applied, the film is in a share mode such that it has an increase in light transmission and the difference in transmission between the privacy mode and the share mode is at least 5% for viewing angles from about 30° to about 45°, and the film has a light transmission of at least about 25% in share and privacy modes at viewing angles from 0° to about 15°.

2. The privacy device of claim 1 , wherein the electronically switchable material comprises an organic electrochromic material.

3. The privacy device of claim 2 , wherein the organic electrochromic material is at least one of a surface-bound viologen dye, a phenothiazine, a diarylethene, or an electrically conductive polymer.

4. The privacy device of claim 3 , wherein the electrically conductive polymer is at least one of a polyaniline, a polypyrrole, a polyphenylene vinylene, a polyphenylene ethynylene, a polyalkoxythiophene or a polyfluorene.

5. The privacy device of claim 4 , wherein the electrochromic material comprises an electrically conductive polymer that comprises a polyethylenedioxythiophene.

6. The privacy device of claim 1 , wherein the electronically switchable layer comprises an interpenetrating network of an electrically conductive polymer and a gel electrolyte material.

7. The privacy device of claim 6 , wherein the electronically switchable layer comprises a crosslinking unit, and wherein the crosslinking unit is ethylene glycol diacrylate.

8. The privacy device of claim 1 , wherein the spacer element is a plurality of spacer beads.

9. The privacy device of claim 1 , wherein the transparent electrode material disposed on the at least one channel wall is disposed on both of the channel walls in the corresponding plurality of the channels.

10. The privacy device of claim 1 , wherein at least some of the transparent electrode members in the plurality of transparent electrode members each has a unitary construction comprising the transparent electrode material disposed continuously on both of the channel walls and across a channel floor defined by a portion of the second substrate extending between adjacent ribs.

11. The privacy device of claim 1 , wherein each rib of the second transparent electrode layer has a height from about 25 micrometers to about 150 micrometers and a width from about 25 micrometers to about 50 micrometers.

12. The privacy device of claim 1 , wherein each rib has height H, width W and rib aspect ratio H/W greater than about 1.5.

13. The privacy device of claim 1 , wherein each channel of the second transparent electrode layer has a height from about 25 micrometers to about 150 micrometers and a width from about 1 to about 50 um.

14. The privacy device of claim 1 , wherein each channel has height H, width Y and channel aspect ratio H/Y greater than 5.

15. The privacy device of claim 1 , wherein the first transparent electrode layer is spaced apart from the second transparent electrode layer at a minimum distance of from about 25 micrometers to about 150 micrometers.

16. An article comprising:
the privacy device of claim 1 ; and
circuitry for supplying the direct current voltage.

17. A display device comprising:
a display pixel array;
a display cover surface adjacent the display pixel array, the display cover surface comprising a viewing surface opposite the display pixel array; and
the privacy device of claim 1 disposed on the viewing surface.

18. A display device of claim 17 , wherein the privacy device of claim 1 is disposed between the display pixel array and the display cover surface.

19. The display device of claim 18 , wherein the display cover surface comprises a touch sensor.

Assignees

• 3M Innovative Properties Co

Inventors

• Schwartz Evan L
• Pellerite Mark J
• Hao Encai
• Steiner Michael L

Classifications

• G02F1/1323 Primary

  Arrangements for providing a switchable viewing angle · CPC title

• G02B26/02

  for controlling the intensity of light {(G02B26/004 takes precedence)} · CPC title

• G02F1/161

  Gaskets; Spacers; Sealing of cells; Filling or closing of cells · CPC title

• G02F1/1521

  Physics · mapped topic

• G02F2001/1557

  Side by side arrangements of working and counter electrodes · CPC title