Band-gap tunable elastic optical multilayer fibers

Patent metadata

Field	Value
Publication number	US-10146007-B2
Application number	US-201414760306-A
Country	US
Kind code	B2
Filing date	Jan 23, 2014
Priority date	Jan 23, 2013
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

The rolled photonic fibers presents two codependent, technologically exploitable features for light and color manipulation: regularity on the nanoscale that is superposed with microscale cylindrical symmetry, resulting in wavelength selective scattering of light in a wide range of directions. The bio-inspired photonic fibers combine the spectral filtering capabilities and color brilliance of a planar Bragg stack compounded with a large angular scattering range introduced by the microscale curvature, which also decreases the strong directional chromaticity variation usually associated with flat multilayer reflectors. Transparent and elastic synthetic materials equip the multilayer interference fibers with high reflectance that is dynamically tuned by longitudinal mechanical strain. A two-fold elongation of the elastic fibers results in a shift of reflection peak center wavelength of over 200 nm.

First claim

What is claimed is:

1. A tunable band-gap multilayer fiber, comprising:
a central core extending along the length of the fiber, wherein the central core has a diameter in the range of 10 μm to 500 μm;
a first polymer layer having a first refractive index; and
a second layer having a second refractive index, wherein the first and second polymer layers are positioned adjacent to one another to form a bilayer and wherein the first and second refractive indices are selected to provide interference of light reflected from the optical interfaces between layers;
wherein the bilayer is concentrically wound around the central core to provide a multilayer cladding having a jelly roll structure, wherein the tunable band-gap multilayer fiber is reversibly expandable to 200% of its length.

2. The tunable band-gap multilayer fiber of claim 1 , wherein the second layer comprises a polymer.

3. The tunable band-gap multilayer fiber of claim 1 , wherein the second layer comprises a metal.

4. The tunable band-gap multilayer fiber of claim 1 , wherein the central core comprises a glass fiber.

5. The tunable band-gap multilayer fiber of claim 1 , wherein the central core comprises a polymer fiber.

6. The tunable band-gap multilayer fiber of claim 5 , wherein the central core comprises an elastomer fiber.

7. The tunable band-gap multilayer fiber of claim 5 , wherein the polymer fiber is capable of being reversibly stretched and/or laterally compressed.

8. The tunable band-gap multilayer fiber of claim 1 , wherein the central core is hollow.

9. The tunable band-gap multilayer fiber of claim 1 , wherein the central core is a space defining an open central axis.

10. The tunable band-gap multilayer fiber of claim 1 , wherein the first and second layers comprise an elastomer, or the first and second layers are capable of being reversibly stretched and/or laterally compressed.

11. The tunable band-gap multilayer fiber of claim 1 , wherein the first and second layer have a layer thickness in the range of 50-300 nm.

12. The tunable band-gap multilayer fiber of claim 1 , wherein the multilayer cladding comprises 10-200 bilayer windings.

13. The tunable band-gap multilayer fiber of claim 1 , wherein the periodicity of the wound bilayers is the same.

14. The tunable band-gap multilayer fiber of claim 1 , wherein the fiber comprises regions of wound bilayers having different periodicities.

15. The tunable band-gap multilayer fiber of claim 1 , wherein the fiber comprises regions of wound bilayers having a controlled gradient in periodicity.

16. The tunable band-gap multilayer fiber of claim 1 , further comprising a third layer positioned adjacent to the bilayer to form a trilayer.

17. The tunable band-gap multilayer fiber of claim 16 , wherein the third layer is a metal layer.

18. The tunable band-gap multilayer fiber of claim 1 , further comprising a patterning or axial variation/axial symmetry breaking imposed by a one or several micron-sized objects or patterns on the initial bilayer/trilayer incorporated in the cladding during rolling.

19. A method of making a tunable band-gap multilayer fiber, comprising:
(a) providing:
(i) a central core extending along the length of the fiber, wherein the central core has a diameter in the range of 10 μm to 500 μm;
(ii) a first polymer layer having a first refractive index; and
(iii) a second layer having a second refractive index, wherein the first and second layers are positioned adjacent to one another to form a bilayer and wherein the first and second refractive indices are selected to provide interference of light reflected from the optical interfaces between layers, wherein the tunable band-gap multilayer fiber is reversibly expandable to 200% of its length;

(b) positioning the central core on the bilayer; and
(c) winding the bilayer concentrically around the central core to form a multilayer cladding.

20. The method of claim 19 , wherein the central core is positioned at an edge of the bilayer and the wound bilayer has a uniform periodicity.

21. The method of claim 19 , wherein the central core is positioned at a location offset from an edge of the bilayer, and the wound bilayer has wound layers of different periodicity.

22. The method of claim 19 , wherein the bilayer is extended for at least a portion of its length during winding, wherein the thickness of the wound layers is varied to obtain a controlled gradient in thickness.

23. The method of claim 19 , further comprising removing the central core after winding.

24. The method of claim 19 , wherein the central core comprises a glass fiber.

25. The method of claim 19 , wherein the central core comprises a polymer fiber core.

26. The method of claim 25 , wherein the multilayer fiber comprises an elastomer in the core, and/or the polymer fiber core is capable of being reversibly stretched and/or laterally compressed.

27. The method of claim 19 , wherein the first and second layers comprise an elastomer or the first and second layers are capable of being reversibly stretched and/or laterally compressed.

28. The method of claim 19 , wherein the first and second layer have a layer thickness in the range of 50 nm-300 nm.

29. The method of claim 19 , wherein the wound bilayer comprises 10-200 windings.

30. The method according to claim 19 , wherein the periodicity of the wound bilayers is the same.

31. The method according to claim 19 , wherein the second layer is a metal layer.

32. The method according to claim 19 , further comprising providing a third layer positioned adjacent to the bilayer to form a trilayer.

33. The method of claim 32 , wherein the third layer is a metal layer.

34. A tunable band-gap multilayer fiber, comprising:
a central core extending along the length of the fiber, wherein the central core has a diameter in the range of 10 μm to 500 μm;
a first polymer layer having a first refractive index; and
a second layer having a second refractive index, wherein the first and second polymer layers are positioned adjacent to one another to form a bilayer and wherein the first and second refractive indices are selected to provide interference of light reflected from the optical interfaces between layers;
wherein the bilayer is concentrically wound around the central core to provide a multilayer cladding having a jelly roll structure, wherein at least one of the first layer and the second layer comprises an elastomer and the tunable band-gap multilayer fiber is reversibly expandable to 200% of its length.

Assignees

• Harvard College
• Univ Exeter

Inventors

• Aizenberg Joanna
• Kolle Mathias
• Vukusic Peter
• Howe Robert D

Classifications

• G02B6/0285

  Graded index layer adjacent to the central core segment and ending at the outer cladding index · CPC title

• G02B1/005

  made of photonic crystals or photonic band gap materials (photonic band-gap structures or photonic lattices in integrated optics G02B6/1225; photonic band-gap structures or photonic lattices in optical fibres G02B6/02295) · CPC title

• G01L1/242

  the material being an optical fibre · CPC title

• G02B6/023

  having different index layers arranged around the core for guiding light by reflection, i.e. 1D crystal, e.g. omniguide · CPC title

• G02B6/02304

  Core having lower refractive index than cladding, e.g. air filled, hollow core · CPC title