Polarization maintaining optical fiber array
Advantageously, at least one embodiment of the present disclosure comprises a polarization maintaining PROFA (“PM-PROFA”) coupler in which the polarization axes of the individual vanishing core waveguides thereof are oriented or aligned without the need to adjust the orientation of each individual VC waveguide.
1. An optical coupler array, comprising:
an optical element having a first end configured to receive light, the optical element further having a second end operable to optically couple with an optical device, the optical element comprising a plurality of longitudinal waveguides;
linear to circular polarization converters disposed before the plurality of longitudinal waveguides, the converters configured to receive linearly polarized light and transmit circularly polarized light to the plurality of longitudinal waveguides; and
a quarter wave retarder disposed at the second end configured to receive the circularly polarized light from the plurality of longitudinal waveguides and transmit linearly polarized light to the optical device,
wherein the plurality of longitudinal waveguides comprises at least one vanishing core waveguide.
2. The optical coupler array of claim 1 , wherein the quarter wave retarder is attached to the optical element.
3. The optical coupler array of claim 1 , wherein the quarter wave retarder is attached to the optical device.
4. The optical coupler array of claim 1 , wherein the quarter wave retarder is a free-standing plate.
5. The optical coupler array of claim 1 , wherein the quarter wave retarder comprises a film.
6. The optical coupler array of claim 5 , wherein the film is a liquid crystal film.
7. The optical coupler array of claim 1 , wherein the transmitted linearly polarized light has polarization axes oriented by the quarter wave retarder.
8. The optical coupler array of claim 7 , wherein the transmitted linearly polarized light for different longitudinal waveguides has polarization axes aligned in the same direction by the quarter wave retarder.
9. The optical coupler array of claim 7 , wherein the orientation of the transmitted linearly polarized light for different longitudinal waveguides is independent of physical orientations of the plurality of longitudinal waveguides.
10. The optical coupler array of claim 1 , wherein the plurality of longitudinal waveguides comprises a plurality of polarization maintaining fibers configured to maintain circularly polarized light.
11. The optical coupler array of claim 1 , wherein the plurality of longitudinal waveguides comprises a plurality of vanishing core waveguides.
12. The optical coupler array of claim 1 , wherein a linear to circular polarization converter of the linear to circular polarization converters comprises:
a twisting region comprising a twist profile, the twisting region having a first region end and a second region end, the first region end disposed proximal, at, or within a portion of a first optical fiber, the second region end disposed proximal, at, or within a section of a second optical fiber.
13. The optical coupler array of claim 12 , wherein the first or second optical fiber is spliced to the plurality of longitudinal waveguides.
14. The optical coupler array of claim 12 , wherein the twist profile comprises a uniform twist.
15. The optical coupler array of claim 12 , wherein the twist profile comprises an accelerated twist configured in accordance with a power function.
16. The optical coupler array of claim 12 , wherein the first or second optical fiber comprises a polarization maintaining fiber.
17. The optical coupler array of claim 1 , further comprising a coupler housing, wherein at least one of the linear to circular polarization converters is disposed outside of the coupler housing.
18. The optical coupler array of claim 1 , further comprising a coupler housing, wherein at least one of the linear to circular polarization converters is disposed at least partially within the coupler housing.
19. The optical coupler array of claim 18 , wherein at least one of the linear to circular polarization converters is disposed before any tapering of the plurality of longitudinal waveguides.
20. The optical coupler array of claim 18 , wherein at least one of the linear to circular polarization converters comprises optical fibers that are untapered.