Optical subassembly structure

1. An optical subassembly structure for mode conversion by an active alignment of an optical fiber with a semiconductor optical waveguide, the optical subassembly structure comprising: a sub-mount for holding the optical subassembly structure; a semiconductor die mounting on the sub-mount; the semiconductor optical waveguide grown on the semiconductor die; and a glass capillary subassembly actively aligned to the semiconductor optical waveguide, wherein the glass capillary subassembly further comprises a glass capillary block, and an optical fiber subassembly, the glass capillary block further comprises a glass capillary tube extending from a front surface and a funnel-shaped hole extending from a back surface that is opposite the front surface, the glass capillary tube is positioned co-linearly to the funnel-shaped hole where the center of the funnel-shaped hole is offset from the center of the back surface of the glass capillary block.

2. The optical subassembly structure as claimed in claim 1 , wherein the glass capillary block is a glass capillary array block.

3. The optical subassembly structure as claimed in claim 2 , wherein the glass capillary array block further comprises a plurality of optical fibers.

4. The optical subassembly structure as claimed in claim 3 , wherein the optical subassembly structure further comprises the glass capillary array block, at least two semiconductor optical waveguides, and a waveguide array.

5. The optical subassembly structure as claimed in claim 4 , wherein the waveguide array further comprises an optical waveguide in between the at least two semiconductor optical waveguides.

6. The optical subassembly structure as claimed in claim 1 , wherein the optical fiber subassembly is any one of a single optical fiber subassembly and a multi-optical fiber subassembly.

7. The optical subassembly structure as claimed in claim 6 , wherein the single optical fiber subassembly further comprises an optical fiber enclosed in an optical fiber jacket.

8. The optical subassembly structure as claimed in claim 6 , wherein the multi- optical fiber subassembly comprises a plurality of optical fibers fusion spliced with at least one optical fiber enclosed in an optical fiber jacket.

9. The optical subassembly structure as claimed in claim 1 , wherein the glass capillary subassembly further comprises a mode convertor.

10. The optical subassembly structure as claimed in claim 9 , wherein the mode convertor is any one of an internal mode convertor and an external mode convertor.

11. The optical subassembly structure as claimed in claim 6 , wherein the optical fiber subassembly inserted in a glass capillary tube of the glass capillary block acts as internal mode convertor.

12. The optical subassembly structure as claimed in claim 10 , wherein the external mode convertor is actively aligned to a single optical fiber subassembly on a front surface of the glass capillary block.

13. The optical subassembly structure as claimed in claim 6 , wherein the optical fiber subassembly is actively aligned to the semiconductor optical waveguide.

14. The optical subassembly structure as claimed in claim 1 , wherein the glass capillary subassembly further comprises an optical connector.

15. The optical subassembly structure as claimed in claim 1 , wherein a front surface of the glass capillary tube and a front surface of the optical fiber subassembly aligns in a coplanar plane.

16. The optical subassembly structure as claimed in claim 1 , wherein a distance between the sub-mount and the glass capillary block is less than 1 mm.

17. The optical subassembly structure as claimed in claim 1 , wherein the optical subassembly structure further comprises a direct butt coupling of the glass capillary subassembly with the semiconductor optical waveguide at an edge of the semiconductor die.