Refractive-Diffractive Multifocal Lens

Abstract

Aspects of the present invention provide multifocal lenses having one or more multifocal inserts comprising one or more diffractive regions. A diffractive region of a multifocal insert of the present invention can provide a constant optical power or can provide a progression of optical power, or any combination thereof. A multifocal insert of the present invention can be fabricated from any type of material and can be inserted into any type of bulk lens material. A diffractive region of a multifocal insert of the present invention can be positioned to be in optical communication with one or more optical regions of a host lens to provide a combined desired optical power in one or more vision zones. Index matching layers of the preset invention can be used to reduce reflection losses at interfaces of the host lens and multifocal insert.

1 - 13 . (canceled) 
     
     
         14 . An ophthalmic lens having a far distance zone, comprising:
 a diffractive optical power region for providing a first incremental add power;   a discontinuity located between the far distance zone and said diffractive optical power region; and   a progressive optical power region for providing a second incremental add power, wherein at least a portion of said diffractive optical power region and said progressive optical power region are in optical communication such that said first incremental add power and said second incremental add power together provide a near distance add power for a user.   
     
     
         15 . The ophthalmic lens of claim  1 , further comprising:
 a distance of said progressive optical power region corresponding to intermediate distance vision correction over which the optical power is constant.   
     
     
         16 . The ophthalmic lens of claim  2 , wherein said distance of said progressive optical power region has a length of approximately 1 millimeter to approximately 6 millimeters or greater. 
     
     
         17 . The ophthalmic lens of  claim 14 , further comprising:
 a blending of optical efficiency across at least a portion of said discontinuity.   
     
     
         18 . The ophthalmic lens of  claim 17 , wherein at least a portion of said blending of optical efficiency occurs over a distance of approximately 2 millimeters or less. 
     
     
         19 . The ophthalmic lens of  claim 14 , wherein a portion of said lens provides an optical add power for intermediate distance vision correction and said optical add power is between 45% and 55% of the optical add power required for providing a user's near distance vision correction. 
     
     
         20 . The ophthalmic lens of  claim 14 , wherein the lens has a fitting point, and wherein the top of said diffractive optical power region is between approximately 2 millimeters and approximately 5 millimeters below said fitting point and the top of said progressive optical power region is between approximately 4 millimeters and approximately 8 millimeters below the top of said diffractive optical power region. 
     
     
         21 . The ophthalmic lens of  claim 14 , wherein said discontinuity is caused by a step in optical power. 
     
     
         22 . The ophthalmic lens of  claim 14 , wherein said diffractive optical power region is located on a surface of the lens or embedded within the lens. 
     
     
         23 . The ophthalmic lens of  claim 14 , wherein said progressive optical power region is located on a surface of the lens or embedded within the lens. 
     
     
         24 . The ophthalmic lens of  claim 14 , wherein said progressive optical power region comprises a progressive optical power surface generated by one of free-forming, molding, or casting. 
     
     
         25 . The ophthalmic lens of  claim 14 , wherein said diffractive optical power region is generated by one of free-forming a surface of the lens, molding a surface of the lens, or casting a surface of the lens. 
     
     
         26 . The ophthalmic lens of  claim 14 , wherein a portion of said lens provides an optical add power for far-intermediate distance vision correction and said optical add power is between 20% and 44% of the optical add power required for providing a user's near distance vision correction. 
     
     
         27 . The ophthalmic lens of  claim 14 , farther comprising a near distance vision correction zone and a far-intermediate distance vision correction zone, wherein said progressive optical power region provides the optical add power for the far-intermediate distance vision correction zone in an area below the near distance vision correction zone. 
     
     
         28 . A lens, comprising:
 a first layer having a first index of refraction, wherein the first layer comprises a far distance zone and a first optical element; and   a second layer having a second index of refraction different from the first index of refraction, wherein the second layer comprises a far distance zone and a second optical element,   wherein an optical discontinuity occurs at a boundary of the first optical element and the far distance zone of the first layer due to a step-up in optical power between the first optical element and the far distance zone of the first layer,   wherein the first optical element is located 4 millimeters below a fitting point of the lens,   wherein the second optical element comprises a progressive optical power region, the progressive optical power region contributing a second portion of a total near distance add power of the lens, and   wherein the first and second optical elements are in optical communication such that a first portion of the total near distance add power of the lens and the second portion of the total near distance add power of the lens are combined to provide the total near distance add power of the lens.   
     
     
         29 . The lens of  claim 28 , wherein the first and second optical elements are aligned to form far-intermediate and intermediate vision zones. 
     
     
         30 . The lens of  claim 29 , wherein the far-intermediate vision zone has an add power between approximately 20% and approximately 44% of the total near distance add power of the lens and the intermediate vision zone has an add power between approximately 45% and approximately 55% of the total near distance add power of the lens. 
     
     
         31 . A lens comprising:
 a first layer having a first index of refraction and having a first external surface and a second internal surface,   a second layer having a second index of refraction different from the first index of refraction and having a first internal surface and second external surface,   wherein the second internal surface of the first layer and the first internal surface of the second layer are in physical contact to form a single interface, and   wherein said interface comprises two optical zones, and   wherein the second external surface of the second layer provides a progression in optical power, and   wherein an optical zone of said interface and the progression in optical power are in optical communication for providing a combined optical power for correcting the near distance vision of a user.   
     
     
         32 . The lens of  claim 31 , wherein one of the optical zones is diffractive and comprises surface relief diffractive structures. 
     
     
         33 . The lens of  claim 31 , wherein there is a discontinuity in optical power between the two optical zones.