Optical construction and display system incorporating same

Patent metadata

Field	Value
Publication number	US-10649274-B2
Application number	US-201514865892-A
Country	US
Kind code	B2
Filing date	Sep 25, 2015
Priority date	Apr 15, 2009
Publication date	May 12, 2020
Grant date	May 12, 2020

Abstract

Optical constructions are disclosed. A disclosed optical construction includes a reflective polarizer layer, and an optical film that is disposed on the reflective polarizer layer. The optical film has an optical haze that is not less than about 50%. Substantial portions of each two neighboring major surfaces in the optical construction are in physical contact with each other. The optical construction has an axial luminance gain that is not less than about 1.2.

First claim

What is claimed is:

1. An optical construction comprising:
a reflective polarizer layer comprising alternating layers, wherein at least one of the alternating layers comprises a birefringent material; and
an optical film comprising a plurality of interconnected voids comprising surface voids and interior voids, the optical film disposed on the reflective polarizer layer and having an optical haze that is not less than about 50%, an optical clarity that is not greater than about 10% and an effective index of refraction that is less than about 1.4, wherein substantial portions of each two neighboring major surfaces in the optical construction are in physical contact with each other, and wherein the optical construction has an axial luminance gain that is not less than about 1.2 and a thickness that is not less than about 1 micron.

2. The optical construction of claim 1 , wherein the optical film has an optical haze that is not less than about 60%.

3. The optical construction of claim 1 , wherein the optical film has an optical haze that is not less than about 70%.

4. The optical construction of claim 1 , wherein the optical film has an optical haze that is not less than about 80%.

5. The optical construction of claim 1 , wherein the optical film has an optical haze that is not less than about 90%.

6. The optical construction of claim 1 , wherein the optical film has a thickness that is not less than about 2 microns.

7. The optical construction of claim 1 , wherein the optical film comprises:
a binder;
a plurality of interconnected voids; and
a plurality of particles, wherein a weight ratio of the binder to the plurality of the particles is not less than about 1:2.

8. The optical construction of claim 7 , wherein the plurality of interconnected voids has an average void size that is not greater than about 2 microns.

9. The optical construction of claim 7 , wherein the plurality of interconnected voids has an average void size that is not greater than about 1 micron.

10. The optical construction of claim 7 , wherein a volume fraction of the plurality of the interconnected voids in the optical film is not less than about 20%.

11. The optical construction of claim 7 , wherein a volume fraction of the plurality of the interconnected voids in the optical film is not less than about 40%.

12. The optical construction of claim 7 , wherein the plurality of particles has an average size that is not greater than about 100 nm.

13. The optical construction of claim 7 , wherein the plurality of particles has an average size that is not greater than about 50 nm.

14. The optical construction of claim 7 , wherein the plurality of particles comprises elongated particles.

15. The optical construction of claim 1 , wherein at least 50% of each two neighboring major surfaces of the optical construction are in physical contact with each other.

16. The optical construction of claim 1 , wherein at least 70% of each two neighboring major surfaces of the optical construction are in physical contact with each other.

17. The optical construction of claim 1 , wherein at least 90% of each two neighboring major surfaces of the optical construction are in physical contact with each other.

18. The optical construction of claim 1 , wherein the optical film is laminated to the reflective polarizer layer via an optical adhesive layer.

19. The optical construction of claim 1 , wherein the optical film is coated on the reflective polarizer layer.

20. The optical construction of claim 1 having an axial luminance gain of no less than about 1.3.

21. The optical construction of claim 1 having an axial luminance gain of no less than about 1.4.

22. The optical construction of claim 1 further comprising an optical adhesive layer disposed on the reflective polarizer layer.

23. The optical construction of claim 1 further comprising a liquid crystal panel disposed on the reflective polarizer layer.

24. The optical construction of claim 1 , wherein the optical film has an optical clarity that is not greater than about 7%.

25. A direct-lit display system comprising:
the optical construction of claim 1 ; and
at least one lamp facing the optical construction.

26. The direct-lit display system of claim 25 , wherein the at least one lamp is at least partially within a reflective optical cavity.

27. An edge-lit display system comprising:
a lightguide;
a lamp disposed along an edge of the lightguide; and

the optical construction of claim 1 disposed on the lightguide.

28. An optical construction comprising:
a reflective polarizer layer comprising alternating layers, wherein at least one of the alternating layers comprises a birefringent material; and
an optical film disposed on the reflective polarizer layer and having a plurality of interconnected voids comprising surface voids and interior voids, an effective index of refraction that is less than about 1.4, an optical clarity that is not greater than about 10% and an optical haze that is not less than about 50%, wherein substantial portions of each two neighboring major surfaces in the optical construction are in physical contact with each other; wherein the optical film has a thickness that is not less than about 1 micron.

29. The optical construction of claim 28 , wherein the optical film has an optical haze that is not less than about 60%.

30. The optical construction of claim 28 , wherein the optical film has an optical haze that is not less than about 70%.

31. The optical construction of claim 28 , wherein the optical film has an optical haze that is not less than about 80%.

32. The optical construction of claim 28 having an axial luminance gain of no less than about 1.2.

33. The optical construction of claim 28 having an axial luminance gain of no less than about 1.3.

Assignees

• 3M Innovative Properties Co

Inventors

• Hao Encai
• Lu Fei
• Kolb William Blake
• Ostlie Brian W
• Haag Adam D
• Free Michael Benton
• Coggio William D
• Steiner Michael L
• Widagdo Soemantri
• Chen-Ho Kui
• Liu Lan H
• Kamrath Robert F
• Tapio Scott M
• Wheatley John A
• Hoyle Charles D
• Weber Michael F

Classifications

• G02F1/133615

  Edge-illuminating devices, i.e. illuminating from the side · CPC title

• G02F1/133536

  Reflective polarizers (G02F1/13362 takes precedence) · CPC title

• G02B5/3066

  involving the reflection of light at a particular angle of incidence, e.g. Brewster's angle · CPC title

• G02B6/0056

  for producing polarisation effects, e.g. by a surface with polarizing properties or by an additional polarizing elements · CPC title

• G02F1/133602

  Direct backlight · CPC title