Optical film

Patent metadata

Field	Value
Publication number	US-10539722-B2
Application number	US-201013264325-A
Country	US
Kind code	B2
Filing date	Apr 14, 2010
Priority date	Apr 15, 2009
Publication date	Jan 21, 2020
Grant date	Jan 21, 2020

Abstract

Optical film is disclosed. The optical film includes a binder, a plurality of particles, and a plurality of interconnected voids. The volume fraction of the plurality of interconnected voids in the optical film is not less than about 20%. The weight ratio of the binder to the plurality of the particles is not less than about 1:2.

First claim

What is claimed is:

1. An optical film comprising:
a low effective index layer having two major surfaces and comprising:
a binder;
a plurality of particles; and
a plurality of interconnected voids comprising surface voids at a major surface of the low effective index layer and interior voids within the interior of the low effective index layer, wherein:
a volume fraction of the plurality of interconnected voids in the optical film is not less than about 20%, and wherein:
a weight ratio of the binder to the plurality of the particles is not less than about 1:2, and

wherein the low effective index layer has a thickness that is not less than about 1 micron.

2. The optical film of claim 1 , wherein at least some of the plurality of particles comprise reactive groups that are chemically bound to the binder.

3. The optical film of claim 1 , wherein at least some of the plurality of particles do not comprise reactive groups.

4. The optical film of claim 1 , wherein the plurality of particles has an average size that is not greater than about 2 microns.

5. The optical film of claim 1 , wherein the plurality of particles has an average size that is not greater than about 1 micron.

6. The optical film of claim 1 , wherein the plurality of particles comprises elongated or spherical particles.

7. The optical film of claim 1 , wherein the plurality of the interconnected voids has an average void size that is not greater than about 2 microns.

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

9. The optical film of claim 1 , wherein the plurality of the interconnected voids has an average void size that is not greater than about 0.7 microns.

10. The optical film of claim 1 , wherein the volume fraction of the plurality of interconnected voids in the low effective index layer is not less than about 30%.

11. The optical film of claim 1 , wherein the volume fraction of the plurality of interconnected voids in the low effective index layer is not less than about 50%.

12. The optical film of claim 1 , wherein the weight ratio of the binder to the plurality of the particles is not less than about 1:1.

13. The optical film of claim 1 , wherein the weight ratio of the binder to the plurality of the particles is not less than about 2:1.

14. The optical film of claim 1 , wherein an effective index of the optical film is not greater than about 1.35.

15. The optical film of claim 1 , wherein an effective index of the optical film is not greater than about 1.25.

16. The optical film of claim 1 , wherein an effective index of the optical film is not greater than about 1.2.

17. The optical film of claim 1 , wherein an effective index of the optical film is not greater than about 1.15.

18. The optical film of claim 1 having an optical haze that is not greater than about 5%.

19. The optical film of claim 1 having an optical haze that is not greater than about 2%.

20. The optical film of claim 1 having an optical haze that is not greater than about 1%.

21. The optical film of claim 1 having an optical haze that is not less than about 50%.

22. The optical film of claim 1 having an optical haze that is not less than about 70%.

23. The optical film of claim 1 having an optical haze that is not less than about 80%.

24. The optical film of claim 1 having an optical haze that is not less than about 90%.

25. The optical film of claim 1 having an optical clarity that is not greater than about 10%.

26. The optical film of claim 1 having an optical clarity that is not greater than about 5%.

27. The optical film of claim 1 having an optical clarity that is not greater than about 2%.

28. The optical film of claim 1 having an optical clarity that is not less than about 50%.

29. The optical film of claim 1 having an optical clarity that is not less than about 70%.

30. The optical film of claim 1 having an optical clarity that is not less than about 90%.

31. The optical film of claim 1 having a diffuse optical reflectance that is not less than about 30%.

32. The optical film of claim 1 having a diffuse optical reflectance that is not less than about 40%.

33. The optical film of claim 1 having a diffuse optical reflectance that is not less than about 50%.

34. The optical film of claim 1 wherein the low effective index layer has a thickness that is not less than about 2 microns.

35. An optical construction comprising:
a substrate; and
the optical film of claim 1 disposed on the substrate.

36. The optical construction of claim 35 , wherein the substrate comprises a release liner.

37. The optical construction of claim 35 further comprising an optical adhesive layer disposed on the optical film of claim 1 .

38. The optical construction of claim 35 further comprising an optical adhesive layer disposed between the substrate and the optical film of claim 1 .

39. The optical film of claim 1 having an optical haze that is not less than about 80%, wherein light scattered by the optical for normally incident light has a luminance L 1 at zero degrees and a luminance L 2 at 10 degrees, L 1 /L 2 not being less than about 10.

40. The optical film of claim 39 , wherein the optical film has an optical haze that is not less than about 90%.

41. The optical film of claim 39 , wherein L 1 /L 2 is not less than about 20.

42. The optical film of claim 39 , wherein L 1 /L 2 is not less than about 50.

43. The optical film of claim 39 , wherein L 1 /L 2 is not less than about 100.

44. The optical film of claim 1 , wherein the interior voids are connected to a major surface via other voids.

45. An optical film comprising:
a low effective index layer having two major surfaces and comprising:
a binder;
a plurality of elongated particles; and
a plurality of interconnected voids comprising surface voids at a major surface of the low effective index layer and interior voids within the interior of the low effective index layer, wherein:
a volume fraction of the plurality of interconnected voids in the low effective index layer is not less than about 20%,
a thickness of the portion of the low effective index layer is not less than about 1 micron, and wherein:
an optical haze of the optical film is not greater than about 1.5%.

46. The optical film of claim 45 , wherein the elongated particles in the plurality of elongated particles have an average aspect ratio that is not less than about 2.

47. The optical film of claim 45 , wherein the elongated particles in the plurality of elongated particles have an average aspect ratio that is not less than about 3.

48. The optical film of claim 45 , wherein the elongated particles in the plurality of elongated particles have an average aspect ratio that is not less than about 4.

49. The optical film of claim 45 , wherein the volume fraction of the plurality of interconnected voids in the low effective index layer is not less tha

Assignees

• Hao Encai
• Kolb William Blake
• Kolb Brant U
• Ostlie Brian W
• Jing Naiyong
• Free Michael Benton
• Ren Hui
• Brott Robert L
• Lu Fei
• Sherman Audrey A
• Tapio Scott M
• Hoyle Charles David
• Wheatley John A
• 3M Innovative Properties Co

Inventors

• Hao Encai
• Kolb William Blake
• Kolb Brant U
• Ostlie Brian W
• Jing Naiyong
• Free Michael Benton
• Ren Hui
• Brott Robert L
• Lu Fei
• Sherman Audrey A
• Tapio Scott M
• Hoyle Charles David
• Wheatley John A

Classifications

• G02B5/0247 Primary

  by means of voids or pores · CPC title

• G02B5/0242

  by means of dispersed particles · CPC title

• H01J2211/44

  Optical arrangements or shielding arrangements, e.g. filters or lenses · CPC title

• G02B5/0268

  characterized by the fabrication or manufacturing method · CPC title

• G02B5/0278

  used in transmission · CPC title