Method of vision correction

Abstract

A method of vision correction comprising shaping first and second regions of a cornea to provide the first region with a first vision correction power and the second region with a second vision correction power which is different from the first vision correction power to enhance vision at first and second distances, respectively.

1 . A method of vision correction comprising shaping first and second regions of a cornea to provide the first region with a first vision correction power and the second region with a second vision correction power which is different from the first vision correction power to enhance vision at first and second different distances, respectively.  
     
     
         2 . A method of vision correction as defined in    claim 1    wherein the step of shaping is carried out to provide the first region with a near vision correction power and the second region with a far vision correction power.  
     
     
         3 . A method of vision correction as defined in    claim 1    wherein the step of shaping includes shaping an third region of the cornea between said first and second regions to provide progressive vision correction powers which include progressive vision correction powers which are between the first and second vision correction powers.  
     
     
         4 . A method of vision correction as defined in    claim 3    wherein the step of shaping includes shaping a fourth region of the cornea to provide progressive vision correction powers which include progressive vision correction powers which are between the first and second vision correction powers, said second region being between the third region and the fourth region.  
     
     
         5 . A method of vision correction as defined in    claim 1    wherein the step of shaping includes directing laser energy to a mask which modulates the laser energy so the laser energy can shape the first and second regions of the cornea to provide the first and second vision correction powers.  
     
     
         6 . A method of vision correction as defined in    claim 1    including repeating said step of shaping of said cornea.  
     
     
         7 . A method of vision correction comprising 
 shaping first and second annular regions of a cornea to provide the first region with a first vision correction power and the second region with a second vision correction power which is different from the first vision correction power to enhance vision at first and second different distances, respectively; and    shaping a third annular region of the cornea between said first and second regions to provide progressive vision correction powers which include progressive vision correction powers which are between the first and second vision correction powers, said second annular region circumscribing the first annular region.    
     
     
         8 . A method of vision correction as defined in    claim 7    including shaping a fourth annular region of the cornea to provide progressive vision correction powers which include progressive vision correction powers which are between the first and second vision correction powers, said fourth annular region circumscribing the second annular region.  
     
     
         9 . A method of vision correction as defined in    claim 7    including shaping a central region of the cornea to provide a vision correction power intermediate the first and second vision correction powers, said first annular region circumscribing the central region.  
     
     
         10 . A method of vision correction comprising: 
 directing laser energy to a mask to provide a modulated laser beam having different energy levels at different locations across the modulated laser beam; and    directing the modulated laser beam to a cornea of a patient to ablate a region of the cornea to different degrees to provide the cornea with progressive vision correction powers.    
     
     
         11 . A method of vision correction as defined in    claim 10    wherein the step of directing includes ablating first and second annular regions of the cornea to provide such annular regions with progressive vision correction powers, the progressive vision correction powers including progressive vision correction powers which increase in a radial direction across one of the first and second regions and decrease in said radial direction across the other of the first and second regions, said second region circumscribing the first region.  
     
     
         12 . A multifocal cornea having an anterior surface with a first region having a surface configuration which provides a first vision correction power and a second region having a surface configuration which provides a second vision correction power which is different from the first vision correction power to enhance vision at first and second different distances, respectively.  
     
     
         13 . A multifocal cornea as defined in    claim 12    wherein the first and second distances are near and far, respectively.  
     
     
         14 . A multifocal cornea as defined in    claim 12    wherein the first and second regions are annular and the second region circumscribes the first region.  
     
     
         15 . A multifocal cornea as defined in    claim 12    wherein the anterior surface of the cornea has a third region between the first and second regions having a surface configuration which provides progressive vision correction powers which include progressive vision correction powers which are between the first and second vision correction powers.  
     
     
         16 . A multifocal cornea as defined in    claim 15    wherein the anterior surface of the cornea has a fourth region with a surface configuration to provide progressive vision correction powers which include progressive vision correction powers which are between the first and second vision correction powers, said second region being between the third region and the fourth region.  
     
     
         17 . A multifocal cornea as defined in    claim 16    wherein each of said first, second, third and fourth regions of the cornea is annular with the third region circumscribing the first region, the second region circumscribing the third region and the fourth region circumscribing the second region.  
     
     
         18 . A multifocal cornea as defined in    claim 17    wherein the progressive vision correction powers include progressive vision correction powers which increase in a radial direction across one of the third and fourth regions and decrease in said radial direction across the other of the third and fourth regions.  
     
     
         19 . A multifocal cornea as defined in    claim 18    wherein the anterior surface has a central region circumscribed by the first region which provides a vision correction power intermediate the first and second vision correction powers.