Refractive-diffractive multifocal lens
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 present invention can be used to reduce reflection losses at interfaces of the host lens and multifocal insert.
1. A lens, comprising:
an insert having an index of refraction, the insert comprising a refractive region and a diffractive region; and
a host lens having an index of refraction, the host lens comprising a progressive optical power region, wherein the diffractive region and the progressive optical power region are in optical communication,
wherein the insert is embedded within the host lens, and
wherein the progressive optical power region begins at a top of the diffractive region and reaches approximately +0.03 D at approximately 1 mm below the top of the diffractive region.
2. The lens of claim 1 , wherein the insert has a thickness ranging from 0.1 mm to 7 mm.
3. The lens of claim 1 , wherein the insert has a thickness ranging from 50 μm to 500 μm.
4. The lens of claim 1 , wherein the index of refraction of the host lens is larger than the index of refraction of the insert.
5. The lens of claim 1 , further comprising an index matching layer having an index of refraction that matches the index of refraction of at least one of the insert and the host lens.
6. The lens of claim 5 , wherein the index of refraction of the index matching layer is substantially equal to the arithmetic mean of the refractive indices of the insert and the host lens.
7. The lens of claim 1 , wherein the diffractive region provides a substantially constant optical power.
8. The lens of claim 1 , wherein the diffractive region provides a progression of optical power.
9. The lens of claim 1 , wherein the diffractive region is cropped.
10. The lens of claim 1 , wherein the diffractive region provides a first incremental add power and the progressive optical power region provides a second incremental add power, the first and second incremental add powers collectively providing a full near add power of the lens.
11. The lens of claim 10 , wherein the second incremental add power is greater than the first incremental add power.
12. The lens of claim 10 , wherein the first incremental add power is approximately one-third of the full near add power of the lens.
13. The lens of claim 1 , wherein the progressive optical, power region reaches approximately +0.06 D at approximately 2 mm below the top of the diffractive region.
14. The lens of claim 13 , wherein the progressive optical power region reaches approximately +0.1 D at approximately 3 mm below the top of the diffractive region.
15. A lens, comprising:
an insert having an index of refraction, the insert comprising a refractive region and a diffractive region; and
a host lens having an index of refraction, the host lens comprising a progressive optical power region, wherein the diffractive region and the progressive optical power region are in optical communication,
wherein the insert is embedded within the host lens, and
wherein the progressive optical power region begins at a top of the diffractive region, and reaches approximate +0.06 D at approximately 2 mm below the top of the diffractive region.
16. The lens of claim 15 , wherein the progressive optical power region reaches approximately +0.1 D at approximately 3 mm below the top of the diffractive region.
17. The lens of claim 15 , wherein the diffractive region provides a first incremental add power and the progressive optical power region provides a second incremental add power, the first and second incremental add powers collectively providing a full near add power of the lens.
18. The lens of claim 15 , wherein the index of refraction of the hog, lens is larger than the index of refraction of the insert.