Method and apparatus for coupling optical signals onto a semiconductor chip

1. An apparatus, comprising:

a semiconductor chip;

a turning mirror on the semiconductor chip which is tilted at a specified angle relative to the semiconductor chip, wherein the turning mirror is configured to direct optical signals from an optical fiber onto one or more first optical channels located on the semiconductor chip, wherein the one or more first optical channels have dimensions that are within a specified tolerance of the dimensions of the optical fiber; and

wherein the turning mirror is configured to simultaneously couple multiple wavelengths of substantially surface-normal light with respect to the semiconductor chip to substantially in-plane light with respect to the semiconductor chip;

one or more optical couplers configured to direct the optical signals from the one or more first optical channels to one or more second optical channels located on the semiconductor chip,

wherein the one or more second optical channels have a specified sub-micron size; and

one or more nano-lens structures each including a number of comb fingers, wherein the comb fingers are configured with a predetermined separation between the comb fingers so that the nano-lens structure has an average refractive index of the comb fingers, and wherein the nano-lens structure is configured to direct the optical signals from the one or more first optical channels to one or more second optical channels located on the semiconductor chip.

2. The apparatus of claim 1 , wherein the turning mirror is configured to direct the optical signals to a specified optical channel in the one or more first optical channels.

3. The apparatus of claim 1 , wherein the one or more optical couplers are tapered waveguides.

4. The apparatus of claim 1 , wherein the one or more optical couplers are inverse-tapered waveguides.

5. The apparatus of claim 1 , wherein the one or more second optical couplers are located on the semiconductor chip.

6. The apparatus of claim 1 , wherein the one or more first optical channels are free space optical channels.

7. The apparatus of claim 1 , wherein the one or more first optical channels are wide waveguides with specified dimensions.

8. The apparatus of claim 1 , wherein the one or more second optical channels are waveguides with specified sub-micron sizes.

9. The apparatus of claim 1 , further comprising: an output waveguide configured to receive optical signals processed by the semiconductor chip and which is coupled to a third optical channel so that optical signals traveling within the output waveguide are directed to the third optical channel; and

an additional optical coupler configured to direct optical signals traveling within the third optical channel off of the semiconductor chip.

10. The apparatus of claim 9 , wherein the additional optical coupler is a turning mirror, which is tilted at a specified angle relative to the semiconductor chip.

11. The apparatus of claim 9 , wherein the additional optical channel is a free space optical channel.

12. The apparatus of claim 9 , wherein the additional optical channel is a waveguide with specified dimensions.

13. A computer system, comprising:

a semiconductor chip;

a turning mirror on the semiconductor chip which is tilted at a specified angle relative to the semiconductor chip, wherein the turning mirror is configured to direct optical signals from an optical fiber onto one or more first optical channels located on the semiconductor chip, wherein the one or more first optical channels have dimensions that are within a specified tolerance of the dimensions of the optical fiber and

wherein the turning mirror is configured to simultaneously couple multiple wavelengths of substantially surface-normal light with respect to the semiconductor chip to substantially in-plane light with respect to the semiconductor chip;

one or more optical couplers configured to direct the optical signals from the one or more first optical channels to one or more second optical channels located on the semiconductor chip, and

wherein the one or more second optical channels have a specified sub-micron size; and

one or more nano-lens structures each including a number of comb fingers, wherein the comb fingers are configured with a predetermined separation between the comb fingers so that the nano-lens structure has an average refractive index of the comb fingers, and wherein the nano-lens structure is configured to direct the optical signals from the one or more first optical channels to one or more second optical channels located on the semiconductor chip.

14. A method, comprising:

directing optical signals from an optical fiber onto one or more first optical channels located on a semiconductor chip using a turning mirror on the semiconductor chip which is tilted at a specified angle relative to the semiconductor chip, wherein the one or more first optical channels have dimensions that are within a specified tolerance of the dimensions of the optical fiber and

wherein the turning mirror is configured to simultaneously couple multiple wavelengths of substantially surface-normal light with respect to the semiconductor chip to substantially in-plane light with respect to the semiconductor chip; and

directing the optical signals from the one or more first optical channels to one or more second optical channels located on the semiconductor chip, wherein the one or more second optical channels have a specified sub-micron size,

wherein directing the optical signals from the first optical channels to the one or more second optical channels located on the semiconductor chip involves using one or more nano-lens structures each including a number of comb fingers, wherein the comb fingers are configured with a predetermined separation between the comb fingers so that the nano-lens structure has an average refractive index of the comb fingers to direct the optical signals.