Diffuse multilayer optical assembly

• US 7,924,368 B2
• Filed: 12/08/2005
• Issued: 04/12/2011
• Est. Priority Date: 12/08/2005
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Fabick, Ryan T., Etzkorn, Stephen J., Gehlsen, Mark D.
• Primary Examiner(s): Nelms; David
• Assistant Examiner(s): NGUYEN, THANH NHAN P
• Application Number:
  US11/297,625
• Publication Number:
  US 20070134438A1
• Time in Patent Office: 1,951 Days
• Field of Search: 349/96, 349 61- 71, 349/98, 428/1.1, 428/1.3, 428/1.31
• US Class Current: 349/64
• CPC Class Codes: B32B 2307/414 Translucent
• CPC Class Codes: B32B 2307/416 Reflective
• CPC Class Codes: B32B 2307/42 Polarizing, birefringent, filtering
• CPC Class Codes: B32B 2457/202 LCD, i.e. liquid crystal displays
• CPC Class Codes: B32B 2551/00 Optical elements
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 3/26 characterised by a particular shape of the outline of the cross-section of a continuous layer; characterised by a layer with cavities or internal voids foam layer B32B5/18; layer of synthetic resin characterised by fillers that create voids or cavities B32B27/205; characterised by an apertured layer
• CPC Class Codes: B32B 7/023 Optical properties
• CPC Class Codes: B32B 7/12 using interposed adhesives or interposed materials with bonding properties
• 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: G02B 5/0231 the surface having microprismatic or micropyramidal shape macroscopic prism arrays G02B5/045
• CPC Class Codes: G02B 5/0242 by means of dispersed particles
• CPC Class Codes: G02B 5/0247 by means of voids or pores
• CPC Class Codes: G02B 5/0278 used in transmission
• CPC Class Codes: G02B 5/305 including organic materials, e.g. polymeric layers

Abstract

An optical assembly includes a light diffusing layer attached to a reflective polarizing layer. An intermediate region between the light diffusing layer and the reflective polarizing layer includes an intermediate structure that defines voids between the light diffusing layer and the reflective polarizing layer.

Claims

1. An optical assembly comprising:

a light diffusing layer;

a reflective polarizing layer attached to the light diffusing layer; and

an intermediate region between the light diffusing layer and the reflective polarizing layer, the intermediate region including an intermediate structure that defines voids between the light diffusing layer and the reflective polarizing layer, and wherein the intermediate structure comprises a non-uniform surface on the reflective polarizing layer that is formed by a plurality of topographical features that extend into the intermediate region, wherein adjacent topographical features define the voids;

wherein the non-uniform surface on the reflective polarizing layer comprises an average roughness of about 0.5 to 10 μ

m.

2. The optical display assembly of claim 1, wherein the intermediate region comprises an intermediate layer including a structure that defines the voids.

3. The optical assembly of claim 1, wherein the reflective polarizing layer is attached to the light diffusing layer with an adhesive material.

4. The optical assembly of claim 3, wherein the adhesive material is selected from the group consisting of a pressure sensitive adhesive, a heat-activated adhesive, a hot melt adhesive, and a radiation-curable adhesive.

5. The optical assembly of claim 1, wherein the reflective polarizing layer is attached to the light diffusing layer with bonding selected from the group consisting of perimeter bonding, solvent bonding, ultrasonic welding, and laser welding.

6. The optical assembly of claim 1, wherein the reflective polarizing layer comprises a plurality of alternating polymeric layers.

7. The optical assembly of claim 6, wherein the reflective polarizing layer comprises a dual brightness enhancement film (DBEF).

8. The optical assembly of claim 6, wherein the reflective polarizing layer comprises a diffusely reflective polarizing film (DRPF).

9. The optical assembly of claim 1, and further comprising:

a light directing layer disposed on the reflective polarizing layer opposite the intermediate region.

10. An optical display assembly comprising:

a light gating device;

a light source; and

an optical element disposed between the light source and the light gating device, the optical element comprising;

a light diffusing layer;

a reflective polarizing layer attached to the light diffusing layer; and

an intermediate region between the light diffusing layer and the light management layer, the intermediate region including an intermediate structure that defines voids between the light diffusing layer and the reflective polarizing layer, and wherein the intermediate structure comprises a non-uniform surface on the reflective polarizing layer that is formed by a plurality of topographical features that extend into the intermediate region, wherein adjacent topographical features define the voids;

wherein the non-uniform surface on the reflective polarizing layer comprises an average roughness of about 0.5 to 10 μ

m.

11. The optical display assembly of claim 10, wherein the light gating device is a liquid crystal display (LCD) panel.

12. The optical display assembly of claim 10, wherein the reflective polarizing layer is attached to the light diffusing layer with an adhesive material.

13. The optical display assembly of claim 10, wherein the intermediate region comprises an intermediate layer including a structure that defines the voids.