Intraocular lens

1. An intraocular lens comprising: an anterior surface and a posterior surface and having a substantially antero-posterior optical axis wherein one of these anterior and posterior surfaces includes a first diffractive profile forming at least one first diffractive focal point of order +1 on said optical axis, and a second diffractive profile forming a second diffractive focal point of order +1 on said optical axis which is distinct from said first diffractive focal point of order +1, at least one portion of said second diffractive profile being superposed on at least one portion of said first diffractive profile so that an order +2 of said second diffractive profile is added to said order +1 of said first diffractive profile.

2. An intraocular lens according to claim 1 , wherein said lens is a refractive-diffractive lens with, in said optical axis, a focal point of order zero distinct from said first and second focal points of order +1.

3. An intraocular lens according to claim 2 , wherein said focal point of order zero is a focal point for far vision, said first focal point of order +1 is a focal point for near vision, and said second focal point of order +1 is a focal point for intermediate vision.

4. An intraocular lens according to claim 3 , wherein said focal point for near vision also substantially coincides on the optical axis with a focal point of higher order than +1 formed by the second diffractive profile.

5. An intraocular lens according to claim 3 , wherein said focal point for near vision is at a distance from the focal point for far vision corresponding to inbetween +2.5 diopters and +5 diopters.

6. An intraocular lens according to claim 5 , wherein said focal point for near vision is at a distance from the focal point for far vision corresponding to inbetween +3 diopters and +4 diopters.

7. An intraocular lens according to claim 3 , wherein said second diffractive profile has a smaller amplitude than the first diffractive profile.

8. An intraocular lens according to claim 3 , wherein said first and/or second diffractive profiles are apodized with decreasing amplitude from the optical axis to an outer edge of the lens.

9. An intraocular lens according to claim 8 , wherein said amplitude decreases proportionally to the cube of the radial distance to the optical axis.

10. An intraocular lens according to claim 2 , wherein said lens is aspherical.

11. An intraocular lens according to claim 1 , wherein said first diffractive profile and/or said second diffractive profile are profiles of the kinoform type.

12. An intraocular lens according to claim 11 , wherein edges of said first and/or second diffractive profiles are rounded.

13. An intraocular lens according to claim 4 , wherein said focal point for far vision is at a distance from the focal point for near vision corresponding to inbetween +2.5 diopters and +5 diopters.

14. An intraocular lens according to claim 13 , wherein said focal point for near vision is at a distance from the focal point for far vision corresponding to inbetween +3 diopters and +4 diopters.

15. An intraocular lens according to claim 4 , wherein said second diffractive profile has a smaller amplitude than the first diffractive profile.

16. An intraocular lens according to claim 4 , wherein said first and/or second diffractive profiles are apodized with decreasing amplitude from the optical axis to an outer edge of the lens.

17. An intraocular lens according to claim 16 , wherein said amplitude decreases proportionally to the cube of the radial distance to the optical axis.

18. An intraocular lens according to claim 3 , wherein said first diffractive profile and/or said second diffractive profile are profiles of the kinoform type.

19. An intraocular lens according to claim 18 , wherein edges of said first and/or second diffractive profiles are rounded.

20. An intraocular lens according to claim 5 , wherein said lens is aspherical.