Optical retarders and methods of making the same

• US 20070139771A1
• Filed: 12/15/2005
• Published: 06/21/2007
• Est. Priority Date: 12/15/2005
• Status: Abandoned Application

• Current Assignee: Abraxis Biosensors, LLC
• Original Assignee: Abraxis Biosensors, LLC
• Inventors: Wang, Jian, Deng, Xuegong
• Application Number:
  US11/304,087
• Publication Number:
  US 20070139771A1
• Time in Patent Office: Days
• US Class Current: 359/494
• CPC Class Codes: G02B 5/3083 Birefringent or phase retarding elements G02B5/3008, G02B5/3016 take precedence; systems for polarisation control G02B27/286; manufacturing phase modulating patterns by lithographic processes G03F7/001

Abstract

In certain aspects, the disclosure features an article that includes a first layer having spaced-apart rows of a first material, and a multilayer film adjacent the first layer. The first layer and the multilayer film are each independently birefringent for light of a wavelength λ propagating along an axis that intersects the first layer and the multilayer film, and λ is in a range from about 150 nm to about 5,000 nm.

Claims

1. An article, comprising:

a first layer comprising spaced-apart rows of a first material, and

a multilayer film adjacent the first layer,

wherein the first layer and the multilayer film are each independently birefringent for light of a wavelength λ

propagating along an axis that intersects the first layer and the multilayer film, and λ

is in a range from about 150 nm to about 5,000 nm.

2. The article of claim 1, further comprising a substrate supporting the first layer and the multilayer film.

3. The article of claim 2, wherein the first layer and the multilayer film are disposed on opposite sides of the substrate.

4. The article of claim 2, wherein the first layer and the multilayer film are disposed on the same side of the substrate.

5. The article of claim 2, further comprising a second multilayer film disposed on an opposite side of the substrate to the first multilayer film, the second multilayer film being birefringent for light of wavelength λ

propagating along the axis that intersects the first layer and the multilayer film.

6. The article of claim 5, wherein the structures of the first and second multilayer films are identical.

7. The article of claim 1, wherein the first layer is supported by the multilayer film.

8. The article of claim 1, wherein the multilayer film is supported by the first layer.

9. The article of claim 1, further comprising a second layer disposed between the first layer and the multilayer film.

10. The article of claim 1, wherein rows of the first layer define a first plane and the layers of the multilayer film each define a respective plane parallel to and offset from the first plane.

11. The article of claim 1, wherein the multilayer film comprises alternating layers formed of second and third materials.

12. The article of claim 11, wherein at least one of the second and third materials is a nanolaminate material.

13. The article of claim 12, wherein the first material and at least one of the second and third materials are materials independently selected from a group consisting of SiO₂, SiN_x, Si, Al₂O₃, ZrO₂, Ta₂O₅, TiO₂, HfO₂, Nb₂O₅, and MgF₂.

14. The article of claim 1, wherein the first layer further comprises rows of a second material alternating with the spaced-apart rows of the first material.

15. The article of claim 14, wherein the second material defines a substrate, the rows of the second material are defined by walls of trenches within the substrate, and the first material is disposed within the trenches.

16. The article of claim 15, wherein the first layer further comprises a layer of the first material disposed between the rows of the first layer and the multilayer film.

17. The article of claim 1, wherein the multilayer film comprises a total of at least about 15 layers of each of second and third different materials.

18. The article of claim 17, wherein the multilayer film comprises a total of at least about 35 layers of each of the second and third materials.

19. The article of claim 1, wherein the layers of the multilayer film are each about 100 nm thick or less.

20. The article of claim 1, wherein the article further comprises a second layer comprising spaced-apart rows of a second material, and the second layer is independently birefringent for light of a wavelength λ

propagating along an axis that intersects the first and second layers and the multilayer film.

21. The article of claim 20, wherein the rows of the first material extend along a first direction and the rows of the second layer extend along a second direction non-parallel with the first direction.

22. The article of claim 20, wherein the first and second layers are disposed on a common side of the multilayer film.

23. The article of claim 20, wherein an angle between the first and second directions is about 80°

or less.

24. The article of claim 23, wherein the angle is about 70°

or less.

25. The article of claim 20, wherein the angle between the first and second directions is about 10°

or more.

26. The article of claim 25, wherein the angle is about 20°

or more.

27. The article of claim 20, wherein the first and second layers together retard incident radiation at wavelengths λ

₁ and λ

₂ by respective amounts Γ

₁ and Γ

₂, where |λ

₁−

λ

₂| is at least about 15 nm, Γ

₁ and Γ

₂ are substantially equal, and both λ

₁ and λ

₂ are in a range from about 150 nm to about 5,000 nm.

28. The article of claim 27, wherein |λ

₁−

λ

₂| is at least about 30 nm.

29. The article of claim 27, wherein |λ

₁−

λ

₂| is at least about 75 nm.

30. The article of claim 27, wherein |λ

₁−

λ

₂| is at least about 100 nm.

31. The article of claim 27, wherein |λ

₁−

λ

₂| is at least about 200 nm.

32. The article of claim 27, wherein |Γ

₁−

Γ

₂| is about 0.03π

or less.

33. The article of claim 27, wherein |Γ

₁−

Γ

₂| is about 0.02π

or less.

34. The article of claim 27, wherein |Γ

₁−

Γ

₂| is about 0.01π

or less.

35. The article of claim 22, comprising an antireflection film disposed between the multilayer film and the first and second layers.

36. The article of claim 22, wherein a combined thickness of the first and second layers and the multilayer film is about 10 microns or less.

37. The article of claim 36, wherein a total thickness of the multilayer film is about 2 microns or less.

38. The article of claim 1, wherein the multilayer film comprises a plurality of layers where alternating layers have different refractive indexes at λ

and each of the plurality of layers in the multilayer film has a thickness in a range from about 2 nm to about 500 nm.

39. The article of claim 20, wherein the first and second layers are disposed on opposite sides of the multilayer film.

40. An optical retarder, for light having a wavelength of about 5,000 nm or less, comprising:

a form birefringent a-plate for radiation at a wavelength λ

; and

a form birefringent c-plate for radiation at λ

,

wherein λ

is about 5,000 nm or less.

41. A method, comprising:

using atomic layer deposition to deposit a multilayer film on a surface of a substrate,

wherein the multilayer film is a form birefringent c-plate for light having a wavelength λ and

λ

is in a range from about 150 nm to about 5,000 nm.

42. The method of claim 41, wherein the substrate comprises a form birefringent a-plate, where the a-plate is birefringent for light having wavelength λ

.

43. The method of claim 41, further comprising forming a form birefringent a-plate on the multilayer film, where the a-plate is birefringent for light of wavelength λ

.