Interfacial refraction accommodating lens (IRAL)
This invention relates to intraocular lenses. More particularly, this invention relates to intraocular lenses that have the ability to alter the light refractive power in response to changes in the tension of the ciliary muscle or ciliary body of the eye or any other accommodative forces. Lenses of this invention are generally referred to as interfacial, i.e., lens properties being defined as the interface of two liquids having different refractive indices, refractive accommodating lenses (IRAL).
1. An implantable interfacial refraction ophthalmic lens assembly which adjusts its focal distance in response to changing physiologic needs of a user of said lens, the lens comprising a flexible optic chamber and cooperating haptics:
the optic chamber is defined by opposed, substantially parallel visually transparent circular discs, which are flexibly coupled at their edges and spaced apart to define a closed fluidic chamber, the fluidic chamber including first and second liquids, the liquids having different refractive indices and being immiscible so as to define a spherical or lenticular interface therebetween;
the haptics being coupled to the edge of the optic chamber and to the fluidic chamber so that application of force to the haptics deforms the fluidic chamber and changes the sphericity of the liquid interface;
whereby the focal length of the lens changes in response to application of force to the haptics in response to the changing physiologic need of the user to change the focal distance of the user of the lens without the need for movement of the lens assembly through its optical axis.
2. A lens according to claim 1 wherein the two liquids have substantially the same densities.
3. A lens according to claim 1 wherein the ophthalmic lens assembly is foldable.
4. An implantable interfacial refraction ophthalmic lens assembly which adjusts its focal distance in response to changing physiologic needs of the user of said lens, the lens comprising a flexible optic chamber and cooperating haptics:
the optic chamber is defined by opposed, substantially parallel visually transparent circular discs, which are flexibly coupled at their edges and spaced apart to define a closed fluidic chamber, the fluidic chamber including miscible first and second liquids having different refractive indices, the liquids being separated by an optically-acceptable membrane, the membrane being bonded to the circular disc edges so as to define a spherical or lenticular interface between the liquids;
the haptics being coupled to the edge of the optic chamber and to the fluidic chamber so that application of force to the haptics deforms the fluidic chamber and changes the sphericity of the liquid interface;
whereby the focal length of the lens changes in response to application of force to the haptics to change focus of the user.
5. A lens assembly according to claim 4 wherein the lens assembly is foldable.
6. A lens assembly according to claim 5 wherein the lens is adopted to be implantable into the eye using IOL injectors.
7. A lens assembly according to claim 4 wherein the difference between the refractive indices of the first and second liquids (ΔRI) is at least about 0.1.
8. A lens assembly according to claim 4 wherein the difference between refractive indices (ΔRI) is at least about 0.2.
9. An implantable interfacial refraction accommodating ophthalmic lens assembly which adjusts its focal distance in response to changing physiologic needs of the user of said lens, the lens comprising a flexible optic chamber and cooperating haptics:
the optic chamber is defined by opposed, substantially parallel visually transparent circular discs, which are flexibly coupled at their edges and spaced apart to define a closed fluidic chamber, the fluidic chamber including first and second liquids, the liquids having different refractive indices and being immiscible so as to define a spherical or lenticular interface therebetween;
the haptics being coupled to the edge of the optic chamber and to the fluidic chamber so that application of force to the haptics deforms the fluidic chamber and changes the sphericity of the liquid interface;
wherein the haptics define an internal chamber, the haptic chamber being in fluid communication with the optic chamber so that displacement of the haptics posteriorly permits fluid to flow into the optic chamber.
whereby the focal length of the lens changes in response to application of force to the haptics to change the focus of the user.
10. An ophthalmic lens according to claim 9 wherein the first and second liquids are separated by a visually transparent, elastic membrane.
11. An ophthalmic lens according to claim 9 wherein the membrane is attached to the edges of the circular discs which define the closed fluidic chamber so that the perimeter of the membrane separates, at least in part, the discs.
12. An ophthalmic lens according to claim 9 wherein the membrane has a varying thickness.
13. An ophthalmic lens according to claim 9 wherein the membrane is disposed between the circular discs.