Toric small aperture intraocular lens with extended depth of focus

1. An intraocular lens comprising:

a toric refractive element adapted to counter astigmatism in a human patient's eye;

one or more haptics configured to position the intraocular lens in the eye, the one or more haptics extending from a fixed end disposed at a periphery of the toric refractive element to a free end adapted to contact an inner surface of the eye, the one or more haptics forming an anterior edge of the intraocular lens when implanted in the eye; and

a mask configured to prevent a substantial portion of light from passing through an annular region thereof and to permit light to pass through a central aperture thereof to increase depth of focus, a diameter of the central aperture is at least 0.85 mm and less than or equal to 2.8 mm,

wherein a combination of the toric refractive element and the mask is configured to increase tolerance to rotational misplacement within the patient's eye within a 30 degree window.

2. The intraocular lens of claim 1 , wherein the mask is coupled with a face of an optic incorporating the mask.

3. The intraocular lens of claim 2 , wherein the mask is formed on a piggyback IOL configured to couple with the eye to place the mask on the face of the optic.

4. The intraocular lens of claim 1 , wherein the mask is embedded in an optic comprising the refractive element.

5. The intraocular lens of claim 1 , wherein the mask comprises a plurality of small holes disposed through the annular region to secure the mask to an optic including the refractive element.

6. The intraocular lens of claim 1 , wherein the mask is configured to increase depth of focus by a magnitude equivalent to up to 2 diopters of add power.

7. The intraocular lens of claim 1 , wherein the refractive element comprises a rotational alignment feature.

8. The intraocular lens of claim 1 , wherein the intraocular lens is configured to maintain visual acuity of at least 20/20 from 0.0 diopters to +/− 2.0 diopters of defocus.

9. The intraocular lens of claim 1 , wherein the mask comprises an elastic material.

10. The intraocular lens of claim 1 , wherein the 30 degree window is +/− 15 degrees.

11. The intraocular lens of claim 1 , wherein the intraocular lens is a monofocal intraocular lens.

12. The intraocular lens of claim 1 , wherein the one or more haptics are vaulted with respect to the refractive element.

13. The intraocular lens of claim 1 , wherein the one or more haptics are flat with respect to the refractive element.

14. An intraocular lens comprising:

a toric refractive element adapted to counter astigmatism in a human patient's eye;

one or more haptics configured to position the intraocular lens in the eye, the one or more haptics extending from a fixed end disposed at a periphery of the toric refractive element to a free end adapted to contact an inner surface of the eye, the toric refractive element forming an anterior edge of the intraocular lens when implanted in the eye; and

a mask configured to block a substantial portion of light from passing through an annular region thereof and to permit a substantial portion of light to pass through a central aperture thereof to increase depth of focus;

wherein the intraocular lens is configured to maintain visual acuity of at least 20/20 within +/− 15 degrees of rotational misplacement.

15. The intraocular lens of claim 14 , wherein the one or more haptics are vaulted with respect to the refractive element.

16. The intraocular lens of claim 14 , wherein the one or more haptics are flat with respect to the refractive element.