Accommodating intraocular lens (AIOL), and AIOL assemblies including same
An accommodating intraocular lens (AIOL) including a biasing mechanism for elastically deforming an elastically deformable shape memory disk-like optical element for affording the AIOL a natural positive diopter strength for near vision. The AIOL is intended to be implanted in a human eye such that relaxation of its ciliary body causes its capsular diaphragm to apply an accommodation force for overcoming the biasing mechanism to reduce the AIOL's natural positive diopter strength for distance vision.
1. An accommodating intraocular lens (AIOL) comprising:
(a) a cup shaped casing having a leading surface, a trailing surface with an aperture, and at least one elastically deformable shape memory optical element;
(b) a carriage having a base plate and an aperture lens, and being slidingly mounted on said casing with said base plate lateral to said trailing surface for reciprocation between a first extreme position with said base plate adjacent said trailing surface and a second extreme position with said base plate distanced from said trailing surface relative to said first extreme position; and
(c) a biasing mechanism for urging said carriage relative to said casing towards said second extreme position for deforming said at least one shape memory optical element to at least partially bulge through said aperture to afford the AIOL a natural positive diopter strength for near vision,
said carriage being driven to said first extreme position on application of an external force to said base plate in an opposite direction to said urging direction to allow said at least one shape memory optical element to revert to its natural shape to decrease the AIOL's natural positive diopter strength for distance vision.
2. The AIOL according to claim 1 wherein said biasing mechanism is disposed between said trailing surface and said base plate.
3. The AIOL according to claim 2 wherein said biasing mechanism is a compression spring.
4. The AIOL according to claim 1 wherein said aperture lens has a diopter strength in the range of about +10 to about +30 for basic eyesight correction.
5. The AIOL according to claim 1 wherein said base plate is annular.
6. The AIOL according to claim 1 wherein said aperture lens is lateral to said leading surface.
7. The AIOL according to claim 1 wherein said carriage is externally mounted on said casing.
8. The AIOL according to claim 1 wherein said at least one shape memory optical element has a natural disc-like shape.