Polymeric photonic crystals with co-continuous phases

• US 7,362,943 B2
• Filed: 02/28/2005
• Issued: 04/22/2008
• Est. Priority Date: 02/28/2005
• Status: Expired due to Fees

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Ouderkirk, Andrew J., Leatherdale, Catherine A., Fleming, Patrick R., Brott, Robert L., Benson, Olester Jr., Neavin, Terence D., North, Diane
• Primary Examiner(s): Wood; Kevin S.
• Application Number:
  US11/068,313
• Publication Number:
  US 20060193593A1
• Time in Patent Office: 1,149 Days
• Field of Search: 385/123, 385/125, 385129-132, 385/147
• US Class Current: 385/147
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02B 1/04 made of organic materials, e.g. plastics G02B1/08 takes precedence
• CPC Class Codes: G02B 5/02 Diffusing elements; Afocal elements
• CPC Class Codes: G02B 5/3008 comprising dielectric particles, e.g. birefringent crystals embedded in a matrix
• CPC Class Codes: G02B 6/1225 comprising photonic band-gap structures or photonic lattices

Abstract

An optical element is formed by co-extruding to have an arrangement of polymer scattering fibers within a polymer matrix. The scattering fibers lie substantially parallel to a first axis. The scattering fibers are arranged at positions across the cross-section of the polymer matrix to scatter light transversely incident on the optical element in a direction substantially orthogonal to the first axis. The positions of the scattering fibers across the cross-section of the optical element may be selected so as to form a two-dimensional photonic crystal structure for light transversely incident on the optical element.

Claims

1. A photonic crystal optical body, comprising:

a polymer matrix; and

an arrangement of polymer scattering fibers disposed within the matrix, the scattering fibers being substantially parallel to a first axis, positions of scattering fibers in the arrangement across a cross-section of the polymer matrix being selected so as to form a two-dimensional photonic crystal structure for light incident on the polymer matrix in a direction substantially orthogonal to the first axis.

2. A body as recited in claim 1, wherein the scattering fibers are formed of a first polymer and the matrix is formed of a second polymer, at least one of the first and second polymers being birefringent.

3. A body as recited in claim 2, wherein a refractive index difference between the first and second polymers is greater than 0.05 for light incident on the body in a first polarization state and is less than 0.05 for light incident on the body in a second polarization state orthogonal to the first polarization state.

4. A body as recited in claim 1, wherein at least one of the scattering fibers comprises a disperse phase scattering fiber having a disperse polymer phase in a continuous polymer phase.

5. A body as recited in claim 1, wherein at least a first scattering fiber has a first cross-sectional dimension and at least a second scattering fiber has a second cross-sectional dimension different from the first cross-sectional dimension.

6. A body as recited in claim 1, wherein at least some of the scattering fibers have a cross-sectional dimension in the range 50 nm-1000 nm.

7. A body as recited in claim 6, wherein at least some of the scattering fibers have a cross-sectional dimension in the range 100 nm-500 nm.

8. A body as recited in claim 1, wherein at least some of the scattering fibers have a circular cross-section.

9. A body as recited in claim 1, wherein at least some of the scattering fibers have a non-circular cross-section.

10. A body as recited in claim 9, wherein at least one of the scattering fibers having a non-circular cross-section has a longer cross-sectional direction that is parallel to a longer cross-sectional direction of another of the scattering fibers having a non-circular cross-section.

11. A body as recited in claim 9, wherein at least one of the scattering fibers having a non-circular cross-section has a longer cross-sectional direction that is non-parallel to a longer cross-sectional direction of another of the scattering fibers having a non-circular cross-section.

12. A body as recited in claim 1, wherein at least a first of the scattering fibers has a cross-sectional shape different from a cross-sectional shape of at least a second of the scattering fibers.

13. A body as recited in claim 1, wherein at least one of the scattering fibers comprises a fiber shell surrounding a fiber core.

14. A body as recited in claim 1, wherein the polymer matrix comprises two, substantially parallel, flat major surfaces.

15. A body as recited in claim 1, wherein the polymer matrix comprises at least one structured surface.

16. A body as recited in claim 15, wherein the at least one structured surface comprises a surface that provides optical power to light passing through the structured surface.

17. A body as recited in claim 15, wherein the at least one structured surface comprises a brightness enhancing surface.

18. A body as recited in claim 1, wherein a total cross-sectional area of the scattering fibers comprises at least 1% of the cross-sectional area of the polymer matrix.

19. A body as recited in claim 18, wherein the total cross-sectional area of the scattering fibers comprises at least 10% of the cross-sectional area of the optical element.

20. A body as recited in claim 1, wherein at least a first scattering fiber of the scattering fibers has a substantially uniform cross-sectional dimension along the length of the first scattering fiber.

21. A body as recited in claim 1, wherein at least a first scattering fiber of the scattering fibers has a cross-sectional dimension that varies along the length of the first scattering fiber.

22. A body as recited in claim 21, wherein the cross-sectional dimension of the first scattering fiber has a value of zero at at least one point along the first scattering fiber.

23. An optical system, comprising:

a photonic crystal comprising an arrangement of polymer scattering fibers within a polymer matrix, the scattering fibers being substantially parallel to a first axis; and

a light source arranged and configured to generate a light beam incident on the photonic crystal in a direction orthogonal to the first axis.

24. A system as recited in claim 23, wherein at least one of the polymer scattering fibers and polymer matrix being formed of a birefringent material.

25. A system as recited in claim 23, wherein the polymer matrix forms a sheet.

26. A system as recited in claim 23, further comprising surface structure on the polymer matrix.

27. A system as recited in claim 26, wherein the surface structure comprises a surface that provides optical power to the light.

28. A system as recited in claim 26, wherein the surface structure comprises a brightness enhancing surface.

29. A system as recited in claim 23, wherein the fill factor is non-uniform across the photonic crystal.

30. A system as recited in claim 23, wherein the light has a center wavelength of around λ

₀ in vacuum, and at least some of the scattering fibers have a cross-sectional dimension in the range of around λ

/10 to 2λ

.