ULTRATHIN TRANSPARENT EMI SHIELDING FILTER

• US 20090303602A1
• Filed: 06/05/2008
• Published: 12/10/2009
• Est. Priority Date: 06/05/2008
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: BRIGHT, CLARK I., Le, John D., Maki, Stephen P., Fitzer, Robert C.
• Granted Patent: US 8,350,451 B2
• Time in Patent Office: Days
• US Class Current: 359/585
• CPC Class Codes: G02B 1/111 using layers comprising organic materials
• CPC Class Codes: G02B 1/116 including electrically conducting layers
• CPC Class Codes: G02B 5/287 comprising at least one layer of organic material

Abstract

Provided are multi-component films useful as optical display filters. The films include a transparent substrate, a nucleation layer, an electrically-conductive layer, a barrier layer, and a dielectric layer. The films can provide high visible transmission, are corrosion-resistant, and can provide shielding from electromagnetic interference (EMI shielding). The optical display filters are useful as components of active optical devices such as display panels including liquid crystal display panels such as those used on mobile hand-held phones.

Claims

1. An optical display filter comprising:

a transparent polymeric substrate;

a multi-layer construction adjacent to the substrate, the construction consisting essentially of;

an electrically-conductive layer having a first surface and a second surface;

a nucleation layer in contact with the first surface; and

a barrier layer in contact with the second surface, and

a transparent dielectric layer adjacent to the construction.

2. The filter according to claim 1 wherein the nucleation layer comprises zinc oxide or bismuth oxide.

3. The filter according to claim 1 wherein the electrically-conductive layer comprises silver, copper, rhodium, ruthenium, chromium, aluminum, gold, palladium, platinum, nickel, or zinc.

4. The filter according to claim 1 wherein the barrier layer comprises ZnO, ZnSnO₃, Zn₂SnO₄, In₂O₃, SnO₂, or indium-tin-oxide.

5. The filter according to claim 1 wherein the dielectric layer comprises an acrylate.

6. The filter according to claim 1 wherein the dielectric layer has a refractive index below 1.47.

7. The filter according to claim 1 wherein the dielectric layer has a refractive index greater than 1.49.

8. The filter according to claim 1 wherein the dielectric layer is selected from at least one polymer, organometallic material, and organic-inorganic hybrid material.

9. The filter according to claim 1 further comprising at least one of an antireflection layer, a low friction coating layer, a polarizer, an antistatic layer, an abrasion resistant layer, an anti-fogging material layer, a magnetic or magneto-optic layer, an adhesion promoter, an anti-intrusion layer, a vibration-damping layer, a self-cleaning layer, a color-compensation layer, and an anti-corrosion layer.

10. The filter according to claim 1 further comprising an optically clear adhesive.

11. The filter according to claim 1 wherein the filter has an average optical transmission of greater than 85% between the wavelengths of 450 nm and 650 nm.

12. The filter according to claim 1 wherein the filter has a sheet resistance of less than 300 ohms/square.

13. The filter according to claim 1 wherein the filter provides EMI shielding of less than 30 dB when the frequency is in the range of from 1 GHz to 18 GHz.

14. The filter according to claim 1 further comprising a basecoat layer disposed between the substrate and the nucleation layer.

15. The filter according to claim 1 further comprising a dye or pigment that can absorb in one or more regions of the electromagnetic spectrum.

16. A display panel comprising at least one optical filter according to claim 1.

17. The display panel according to claim 16 wherein the panel is electronically responsive to touch.

18. The display panel according to claim 17 comprising a capacitive touch-sensitive substrate.

19. A device comprising a display panel according to claim 16.

20. A device comprising a display panel according to claim 17.