Polarization rotator

Patent metadata

Field	Value
Publication number	US-9355662-B2
Application number	US-201514728140-A
Country	US
Kind code	B2
Filing date	Jun 2, 2015
Priority date	Dec 4, 2012
Publication date	May 31, 2016
Grant date	May 31, 2016

Abstract

A polarization rotator for a recording head. The polarization rotator comprises a first waveguide coupled to an input coupler at a first end and a second waveguide. The first waveguide is offset from the second waveguide and a second end of the first waveguide is coupled to a second end of the second waveguide.

First claim

The invention claimed is:

1. A light delivery apparatus for a recording head comprising:
an input coupler configured to couple light energy;
a polarization rotator comprising a first waveguide coupled to the input coupler and a second waveguide offset from the first waveguide; and
a near field transducer (NFT) adapter coupled to the polarization rotator.

2. The light delivery apparatus of claim 1 , wherein the polarization rotator is configured to rotate a polarization state of the light energy orthogonally.

3. The light delivery apparatus of claim 2 , wherein the polarization rotator rotates the polarization state of the light energy from transverse electric (TE) polarization state to transverse magnetic (TM) polarization state.

4. The light delivery apparatus of claim 1 , wherein the NFT adapter is configured to have expanded waveguide propagation mode compared to propagation mode of the polarization rotator.

5. The light delivery apparatus of claim 1 , wherein the NFT adapter is configured to have reduced waveguide propagation mode compared to propagation mode of the polarization rotator.

6. The light delivery apparatus of claim 1 , wherein a first end of the first waveguide is coupled to the input coupler and a second end of the first waveguide is coupled to a second end of the second waveguide.

7. The light delivery apparatus of claim 6 , wherein the second end of the first waveguide is also coupled to the NFT adapter.

8. The light delivery apparatus of claim 6 , wherein a second end of the second waveguide is also coupled to the NFT adapter.

9. The light delivery apparatus of claim 8 , wherein a cross-section of the first end of the first waveguide has a width that is substantially twice the thickness of the cross-section of the first end of the second waveguide.

10. The light delivery apparatus of claim 8 , wherein a cross-section of the second end of the first waveguide is substantially similar to cross-section of the second end of the second waveguide.

11. The light delivery apparatus of claim 1 , wherein the input coupler has rectangular end surfaces and trapezoidal side surfaces.

12. The light delivery apparatus of claim 1 , wherein the input coupler has a reverse taper.

13. The light delivery apparatus of claim 1 , wherein the first waveguide has a taper.

14. A polarization rotator for a recording head comprising:
a first waveguide operably coupled to a light source at a first end; and
a second waveguide,

wherein the first waveguide is offset from the second waveguide and a second end of the first waveguide is coupled to a second end of the second waveguide.

15. The polarization rotator of claim 14 , wherein the first waveguide has a taper from its first end to its second end.

16. The polarization rotator of claim 14 , wherein the cross-section of the first end of the first waveguide has a width that is substantially twice the thickness of the cross-section.

17. The polarization rotator of claim 14 , wherein a cross-section of the second end of the first waveguide is substantially similar to cross-section of the second end of the second waveguide.

18. The polarization rotator of claim 14 , wherein the second end of the first waveguide and the second end of the second waveguide are coupled to an NFT adapter.

19. A light delivery apparatus for a data recording head comprising:
an input coupler configured to couple light energy from a laser diode; and
a polarization rotator coupled to the input coupler, wherein the polarization rotator is configured to rotate polarization state of the light energy orthogonally.

20. The apparatus of claim 19 , wherein the polarization rotator rotates the polarization state of the light energy from transverse electric (TE) polarization state to transverse magnetic (TM) polarization state.

Assignees

• Seagate Technology Llc

Inventors

• Peng Chubing
• Zhao Yongjun

Classifications

• G11B5/314 Primary

  where the layers are extra layers normally not provided in the transducing structure, e.g. optical layers (G11B5/3196 takes precedence) · CPC title

• G11B5/4866 Primary

  the arm comprising an optical waveguide, e.g. for thermally-assisted recording · CPC title

• G02B6/126

  using polarisation effects {(G02B6/1226 takes precedence)} · CPC title

• G02B6/2726

  in or on light guides, e.g. polarisation means assembled in a light guide · CPC title

• G02B6/274

  based on light guide birefringence, e.g. due to coupling between light guides (G02B6/105, G02B6/024 take precedence; mechanically induced birefringence G02F1/0134) · CPC title