Intraocular lens systems and methods

Abstract

An intraocular lens ( 31 ) which may be used as a posterior lens in a lens train including a converging anterior lens ( 20 ) and diverging posterior lens ( 31 ) in which the optical/focal axes of the two lenses are not coincident such that the focal point ( 9 ) of the lens train is offset from the focal axis of the anterior lens. Light rays ( 50 ) incident upon the anterior lens parallel to its focal axis may thus be directed ( 51 ) to parts of the retina offset from the fovea where the macula may not have degenerated.

1 - 22 . (canceled) 
     
     
         23 . A posterior intraocular lens apparatus including:
 diverging lens shaped to define as between opposite operative lens surfaces a lens part of minimal lens thickness surrounded by lens parts of greater lens thickness;   a haptic extending from the diverging lens to a first haptic part at an intermediate distance from the lens part of minimal lens thickness, and further extending from the diverging lens to a second haptic part at a maximal distance from the lens part of minimal lens thickness;   wherein the maximal distance is greater than the intermediate distance and the second haptic part opposes the first haptic part across the lens part of minimal lens thickness.   
     
     
         24 . A posterior intraocular lens apparatus according to  claim 23  in which the haptic comprises an arcuate limb incorporating the first and second haptic parts. 
     
     
         25 . A posterior intraocular lens apparatus including:
 diverging lens shaped to define as between opposite operative lens surfaces a lens part of minimal lens thickness surrounded by lens parts of greater lens thickness;   a first haptic extending from the diverging lens to a first haptic part at a first maximal distance from the lens part of minimal lens thickness;   a second haptic separate from the first haptic and extending from the diverging lens to a second haptic part at a second maximal distance from the lens part of minimal lens thickness;   wherein the second maximal distance is greater than the first maximal distance.   
     
     
         26 . A posterior intraocular lens apparatus according to  claim 25  in which the first haptic part opposes the second haptic part across the lens part of minimal lens thickness. 
     
     
         27 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which the one or each of the first and second haptics respectively comprises an arcuate limb. 
     
     
         28 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which the lens part of minimal lens thickness is substantially in the middle of the operative lens surface(s). 
     
     
         29 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which the lens part of minimal lens thickness is offset from the middle of the operative lens surface(s) towards a periphery thereof. 
     
     
         30 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which a plane containing first and second haptic parts contains the lens part of minimal lens thickness. 
     
     
         31 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which the periphery of the diverging lens presents a sighting lug indicating the peripheral part of the diverging lens located between the second haptic part and the lens part of minimal lens thickness. 
     
     
         32 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which the first and second haptic parts are peripheral parts of the apparatus. 
     
     
         33 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which the diverging lens comprises a plano-concave lens. 
     
     
         34 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  in which the diverging lens comprises a concavo-concave lens. 
     
     
         35 . A posterior intraocular lens apparatus according to  claim 23  or  claim 25  wherein in which the diverging lens is flexible. 
     
     
         36 . An intraocular lens apparatus including the posterior intraocular lens according to  claim 23  or  claim 25  and further comprising a converging lens adapted to cooperate with the diverging lens as an anterior intraocular lens. 
     
     
         37 . An intraocular lens apparatus according to  claim 36  in which the converging lens includes one or more haptics which extend away from the converging lens in a direction partially transverse to the plane containing the circumference of the lens to one common side of that plane. 
     
     
         38 . An intraocular lens apparatus according to  claim 36  in which the converging lens is shaped to define as between opposite operative lens surfaces a lens part of maximal lens thickness surrounded by lens parts of lesser lens thickness and includes a third haptic extending from the converging lens to a third haptic part at a third maximal distance from the lens part of maximal lens thickness, and a fourth haptic separate from the third haptic and extending from the converging lens to a fourth haptic part at a fourth maximal distance from the lens part of maximal lens thickness. 
     
     
         39 . A method of providing a lens train for forming an image of an object or scene including:
 providing an intraocular lens apparatus according to  claim 36 ;   placing the converging lens between the diverging lens and the object or scene to be imaged such that an operative lens surface of the converging lens opposes an operative lens surface of the diverging lens and such that the lens part of minimal lens thickness does not oppose the lens part of maximal thickness.   
     
     
         40 . A method of providing a lens train according to  claim 39  including:
 providing a first substantially circular aperture in parallel opposition to a second substantially circular aperture such that the centres of the first and second apertures are in register; 
 mounting the diverging lens within the first aperture such that haptics thereof abut opposing first aperture edges; 
 mounting the converging lens within the second aperture such that haptics thereof abut opposing second aperture edges. 
 
     
     
         41 . A method according to  claim 40  including rotating the mounted diverging lens within the first aperture thereby to revolve the lens part of minimal lens thickness about the centre of the first aperture thereby to select the location of images formable by the lens train in use. 
     
     
         42 . A method of manufacturing a posterior intraocular lens according to  claims 23  or  claim 25  including:
 providing a lens template; 
 shaping inner surface parts of the lens template to define opposite surfaces of a lens between which is defined a lens part of minimal lens thickness surrounded by lens parts of greater lens thickness; 
 shaping outer surface parts of the lens template around said inner surface parts to form said diverging lens and said haptic(s). 
 
     
     
         43 . A method of manufacturing a posterior intraocular lens according to  claim 42  including shaping portions of said inner surface parts defining said lens to form said diverging lens and said haptic(s). 
     
     
         44 . A method of manufacturing a posterior intraocular lens according to  claim 43  including shaping said inner surface parts to form a symmetrical concavity with a circular periphery centred upon the lens part of minimal lens thickness and forming therefrom the diverging lens with a lens periphery centred upon other than the lens part of minimal lens thickness.