Fabrication of an intraocular lens
AssigneePharmacia Corporation
InventorLarry W. Blake
Life of this patent
Estimating the term…
Abstract
A lens, having an optical power surface, which may have multiple radii portions or aspherical portions as well as spherical portions, is molded in a coined mold. A pair of core pins, positioned within the mold cavity during the lens forming process, will produce a pair of haptic-mounting holes within the lens. As the lenses are subsequently tumbled to remove flash, indentations will form adjacent to the haptic-mounting holes. These indentations allow for tangential attachment of the haptic to the lens which, in turn, enables maximum flexibility without exceeding the width of the optic.
Claims9
An intraocular lens, comprising an optical element;
- a pair of haptic-mounting holes;
- indentations along an edge of said optical element, proximate said holes;
- a pair of haptics, adhesively bonded within said holes and extending tangentially therefrom;
- and
- wherein said holes are internally surface coated with a thin layer of fumed silicone dioxide.
An optical power surface, having a radius of curvature defined by the equation:
- ##EQU2## and where:
- R.sub.O =the initial radius of curvature;
- .DELTA.P=the total change in power over a specified area of said surface;
- V=the width of said specified area;
- N.sub.2 =the refractive index of the optical power surface;
- and
- N.sub.1 =the refractive index of aqueous in situ.
An optical power surface having a changing radius of curvature over a predetermined lens region wherein the locus of the center of curvature of said changing radius is arcuate.
An intraocular lens, comprising:
- an optical element, capable of replacing and functioning as a natural human lens, wherein said optical element is biconvex and comprises an anterior side and a posterior side, wherein said anterior side has an aspherical portion that exhibits a gradually decreasing radius of curvature that causes an increase in dioptric power of said optical element,
- wherein said decreasing radius of curvature may be defined at any point by the equation:
- ##EQU3## and where:
- R.sub.O =the initial radius of curvature;
- R.sub.n =the final radius of curvature;
- .DELTA.P=the total change in power of the aspherical portion of the lens from R.sub.0 to R.sub.1 ;
- V=the width of the aspherical portion of the lens;
- N.sub.2 =the index of refraction of the lens;
- and
- N.sub.1 =the index of refraction of air, and at least one haptic, adhesively bonded to said optical element.
An intraocular lens, comprising:
- an optical element, capable of replacing and functioning as a natural human lens, wherein said optical element is biconvex and comprises an anterior side and a posterior side, wherein said anterior side has an aspherical portion that exhibits a gradually decreasing radius of curvature accompanied by a shift in the center of curvature that follows an arcuate path,
- wherein said shift in the center of curvature may be approximated by the equation:
- S.sub.X =V(1-R.sub.X /R.sub.O)
- where R.sub.X =the decreasing radius of curvature;
- R.sub.O =the initial radius of curvature;
- V=the width of the aspherical portion;
- and;
- at least one haptic, adhesively bonded to said optical element.
Dependencies are inferred from the claim text.