Multifocal intraocular lens
View Patent ↗An intraocular lens for providing a subject with vision at various distances includes an optic having a first surface with a first shape, an opposing second surface with a second shape, a multifocal refractive profile, and one or more diffractive portions. The optic may include at least one multifocal diffractive profile. In some embodiments, multifocal diffractive and the multifocal refractive profiles are disposed on different, distinct, or non-overlapping portions or apertures of the optic. Alternatively, portions of the multifocal diffractive profiles and the multifocal refractive profiles may overlap within a common aperture or zone of the optic.
1. An ophthalmic lens, comprising:
an optic comprising a first surface having a first shape and an opposing second surface having a second shape, the shapes together providing a base optic power;
an inner zone disposed about an optical axis, an intermediate zone disposed about the inner zone, and an outer zone disposed about the intermediate zone;
a first diffractive profile imposed on one of the shapes and radially disposed within the inner zone;
a second diffractive profile imposed on one of the shapes and radially disposed within the outer zone;
a multifocal refractive profile imposed on one of the shapes and including a refractive portion radially disposed within the intermediate zone between the first diffractive profile and the second diffractive profile, the multifocal refractive profile including a refractive add portion having refractive add power;
wherein at least one of the diffractive profiles is a multifocal diffractive profile having, for visible light, a primary diffraction order, a secondary diffraction order, and a diffractive add power corresponding to a difference in optical power between the secondary diffraction order and the primary diffraction order; and
wherein the multifocal refractive profile is imposed on the first shape of the first surface of the optic and the multifocal diffractive profile is imposed on the second shape of the opposing second surface of the optic.
2. The ophthalmic lens of claim 1 , wherein the refractive add portion is disposed within the refractive portion of the multifocal refractive profile.
3. The ophthalmic lens of claim 1 , wherein the zones are contiguous.
4. The ophthalmic lens of claim 1 , further comprising a transition zone disposed between zones selected from the group consisting of:
the inner zone and the intermediate zone; and
the intermediate zone and the outer zone.
5. The ophthalmic lens of claim 1 , wherein the refractive profile includes a base portion having a base refractive power of about zero Diopters.
6. The ophthalmic lens of claim 1 , wherein the optical axis passes through the inner zone and the first diffractive profile, the first diffractive profile being the multifocal profile.
7. The ophthalmic lens of claim 1 , wherein the first diffractive profile is disposed on a surface opposite the second diffractive profile.
8. The ophthalmic lens of claim 1 , wherein the primary diffraction order is a zeroth diffraction order having an optical power of about zero Diopters and the secondary diffraction order is a first diffraction order having an optical power that is between about 2 Diopters and about 8 Diopters.
9. The ophthalmic lens of claim 1 , wherein the primary diffraction order is a first diffraction order, the secondary diffraction order is a second diffraction, and the add power is between about 2 Diopter and about 8 Diopters.
10. The ophthalmic lens of claim 1 , wherein the first diffractive profile and the second diffractive profile are both multifocal diffractive profiles, a secondary diffraction order of the second diffractive profile having a diffraction efficiency at a visible light design wavelength that is greater than a secondary diffraction order of the first diffractive profile at the design wavelength.
11. The ophthalmic lens of claim 1 , wherein the first diffractive profile and the second diffractive profile are both multifocal diffractive profiles, a secondary diffraction order of the first diffractive profile having a diffraction efficiency at a visible light design wavelength that is between 15 percent and 25 percent.
12. The ophthalmic lens of claim 11 , wherein a secondary diffraction order of the second diffractive profile has a diffraction efficiency at the design wavelength that is between 25 percent and 25 percent.
13. The ophthalmic lens of claim 1 , wherein the diffractive add power is between about 3 Diopters and about 6 Diopters.
14. The ophthalmic lens of claim 1 , wherein the diffractive add power is less than about 2 Diopters.
15. The ophthalmic lens of claim 1 , wherein the refractive add power is between 1 Diopter and about 4 Diopters.
16. The ophthalmic lens of claim 1 , wherein the refractive add power is equal to the diffractive add power.
17. The ophthalmic lens of claim 1 , wherein at least one of the shapes is characterized over at least one of the zones by an equation having an asphericity constant, an equation having a higher order polynomial in radius from the optical axis, or an equation having both an asphericity constant and a higher order polynomial in radius from the optical axis.
18. The ophthalmic lens of claim 1 , wherein at least one of the zones has a negative spherical aberration.
19. The ophthalmic lens of claim 1 , wherein at least one of the zones includes a monofocal diffractive profile imposed on at least one of the shapes.
20. The ophthalmic lens of claim 1 , further comprising an additional zone having a multifocal profile, wherein the multifocal profile is a multifocal refractive profile or a multifocal diffractive profile.
21. The ophthalmic lens of claim 20 , wherein the additional zone is radially disposed outside the inner zone, outside the intermediate zone, and outside the outer zone.
22. The ophthalmic lens of claim 1 , wherein the first diffractive profile is a first multifocal diffractive profile and has zone has a first optical characteristic, the second diffractive profile is a second multifocal diffractive profile and has zone has a second optical characteristic that is different from the first optical characteristic.
23. The ophthalmic lens of claim 22 , wherein the first optical characteristic is a first diffractive add power and the second optical characteristic is a second diffractive add power, the first and second diffractive add powers differing by at least 0.25 Diopters.
24. The ophthalmic lens of claim 22 , wherein the first optical characteristic is a first step height of echelettes within the inner zone and the second optical characteristic is a second step height of echelettes within the outer zone, the first and second step heights being different.
25. The ophthalmic lens of claim 22 , wherein the first optical characteristic is a first chromatic dispersion and the second optical characteristic is a second chromatic dispersion, the first and second chromatic dispersions being different.
26. The ophthalmic lens of claim 22 , wherein the first optical characteristic is a first diffraction efficiency at a visible light design wavelength and the second optical characteristic is a second diffraction efficiency at the design wavelength, the first diffraction efficiency being different than the second diffraction efficiency.
27. The ophthalmic lens of claim 1 , wherein at least one of the diffractive profiles comprises a plurality of echelettes, each of the echelettes having a different step height, the step heights progressively decreasing with increasing radial distance from the optical axis.
28. An ophthalmic lens, comprising:
an optic comprising a first surface having a first shape and an opposing second surface having a second shape, the shapes together providing a base optic power;
a central zone disposed about and intersecting an optical axis, the central zone including a multifocal diffractive profile imposed on one of the shapes, the multifocal diffractive profile having, for visible light, a primary diffraction order, a secondary diffraction order, and a diffractive add power corresponding to a difference in optical power between the secondary diffraction order and the primary diffraction order; and
a plurality of peripheral zones disposed about the central zone comprising:
a first peripheral zone including a multifocal refractive profile imposed on the first shape of the first surface of the optic and having at least a first refractive power and a second refractive power;
a second peripheral zone including a diffractive profile imposed on the second shape of the opposing second surface of the optic.
29. The ophthalmic lens of claim 28 , wherein the first peripheral zone is disposed about the central zone and second peripheral zone is disposed about the first peripheral zone.
30. The ophthalmic lens of claim 28 , wherein the second peripheral zone is disposed about the central zone and first peripheral zone is disposed about the second peripheral zone.
31. The ophthalmic lens of claim 28 , wherein the diffractive profile of the second peripheral zone is a monofocal profile having only one diffraction order in the visible waveband of the electromagnetic spectrum.
32. The ophthalmic lens of claim 28 , wherein the diffractive profile of the second peripheral zone is a multifocal diffractive profile having, for visible light, a primary diffraction order, a secondary diffraction order, and a diffractive add power corresponding to a difference in optical power between the secondary diffraction order and the primary diffraction order.
33. The ophthalmic lens of claim 28 , wherein the first refractive power and the second refractive power of the first peripheral zone differ by at least 1.5 Diopters.
34. The ophthalmic lens of claim 28 , wherein the plurality of peripheral zones comprises a third peripheral zone disposed about the first and second peripheral zones, the third peripheral zone including a profile, the profile of the third peripheral zone being a diffractive profile or a multifocal refractive profile.
35. The ophthalmic lens of claim 28 , wherein the plurality of peripheral zones comprise at least a third peripheral zone disposed about the first and second peripheral zones, the third peripheral zone having a constant refractive optical power and no diffractive optical power.
36. The ophthalmic lens of claim 28 , wherein the multifocal diffractive profile of the central zone has a first optical characteristic, the diffractive profile of the second peripheral zone is a multifocal diffractive profile having a second optical characteristic, and the first optical characteristic is different from the second optical characteristic.
37. The ophthalmic lens of claim 34 , wherein the first optical characteristic is a first diffractive add power and the second optical characteristic is a second diffractive add power, the first and second diffractive add powers differing by at least 0.25 Diopters.
38. The ophthalmic lens of claim 34 , wherein the first optical characteristic is a first diffractive add power and the second optical characteristic is a second diffractive add power, the first and second diffractive add powers differing by at least 0.25 Diopters.
39. The ophthalmic lens of claim 34 , wherein the first optical characteristic is a first step height of echelettes within the first peripheral zone and the second optical characteristic is a second step height of echelettes within the second peripheral zone, the first and second step heights being different.
40. The ophthalmic lens of claim 34 , wherein the first optical characteristic is a first chromatic dispersion and the second optical characteristic is a second chromatic dispersion, the first and second chromatic dispersions being different.
41. The ophthalmic lens of claim 34 , wherein the first optical characteristic is a first diffraction efficiency at a design wavelength and the second optical characteristic is a second diffraction efficiency at the design wavelength, the first diffraction efficiency being different than the second diffraction efficiency.
42. The ophthalmic lens of claim 28 , wherein at least one of the diffractive profiles comprises a plurality of echelettes, each of the echelettes having a different step height, the step heights decreasing with increasing radial distance from the optical axis.