Multifocal lens with a diffractive optical power region

• US 8,317,321 B2
• Filed: 07/02/2008
• Issued: 11/27/2012
• Est. Priority Date: 07/03/2007
• Status: Active Grant

• Current Assignee: Carl Zeiss Vision International GMBH (Carl-Zeiss-Stiftung)
• Original Assignee: Pixeloptics Incorporated
• Inventors: Haddock, Joshua N., Kokonaski, William, Clarke, Roger, Mattison-Shupnick, Mark, Blum, Ronald D.
• Primary Examiner(s): GREECE, JAMES R
• Application Number:
  US12/166,526
• Publication Number:
  US 20090046349A1
• Time in Patent Office: 1,609 Days
• Field of Search: 351/159, 351/168, 351/169, 351/177, 351/159.11, 351/159.01, 351/159.12, 351/159.15, 351/159.35, 351/159.44, 351/159.75, 359/642
• US Class Current: 351/159.01
• CPC Class Codes: G02B 5/1895 such optical elements having dioptric power
• CPC Class Codes: G02C 2202/20 Diffractive and Fresnel lenses or lens portions
• CPC Class Codes: G02C 7/06 bifocal; multifocal ; progressive G02C7/041 takes precedence
• CPC Class Codes: G02C 7/061 Spectacle lenses with progressively varying focal power
• CPC Class Codes: G02C 7/083 Electrooptic lenses

Abstract

A lens system is presented having a diffractive optical power region. The diffractive optical power region has a plurality of concentric surface relief diffractive structures. A greater portion of light incident on a diffractive structure near the center point contributes to the optical power than light incident on a diffractive structure peripherally spaced therefrom.

Claims

1. A lens system comprising:

a diffractive optical power region comprising a plurality of concentric surface relief diffractive structures having a series of crests and adjacent troughs forming a sawtooth pattern, wherein each concentric surface relief diffractive structure extends from a trough to an adjacent crest of the sawtooth pattern, wherein the distance between a first crest and a first adjacent trough near the center point is greater than the distance between a second crest and a second adjacent trough spaced from the center point, wherein;

the diffractive optical power region includes a first region comprising a plurality of the concentric surface relief diffractive structures for focusing light of a specific wavelength λ

to a focal length f, wherein the radius of the n^th concentric surface relief diffractive structure of the first region from the center point is greater than √

{square root over (2nλ

f)}.

2. The lens system of claim 1, wherein the diffractive optical power region provides a progression of decreasing optical power.

3. The lens system of claim 1, wherein the diffractive optical power region further includes a second region comprising a plurality of the concentric surface relief diffractive structures, wherein the radius of the n^th concentric surface relief diffractive structure of the second region from the center point thereof is approximately equal to √

{square root over (2nλ

f)}.

4. The lens system of claim 3, wherein the second region provides a constant optical power.

5. The lens system of claim 1, wherein the second region is positioned radially interior to the first region.

6. The lens system of claim 1, wherein the radial widths of at least some of the surface relief diffractive structures of the first region are equal to one another.

13. The lens system of claim 1 wherein the lens system is dynamic.

14. The lens system of claim 13, wherein the lens system is electro-active.

7. A lens system comprising:

a diffractive optical power region comprising plurality of concentric surface relief diffractive structures having a series of crests and adjacent troughs forming a sawtooth pattern, wherein each concentric surface relief diffractive structure extends from a trough to an adjacent crest of the sawtooth pattern, wherein the distance between a first crest and a first adjacent trough near the center point is greater than the distance between a second crest and a second adjacent trough spaced from the center point.point, wherein;

the diffractive optical power region includes a first region comprising a plurality of the concentric surface relief diffractive structures for focusing light of a specific wavelength λ

to a focal length f, wherein the radius of the n^th concentric surface relief diffractive structure of the first region from the center point is less than √

{square root over (2nλ

f)}.

8. The lens system of claim 7, wherein the diffractive optical power region provides a progression of increasing optical power.

9. The lens system of claim 7, wherein the diffractive optical power region further includes a second region comprising a plurality of the concentric surface relief diffractive structures, wherein the radius of the n^th concentric surface relief diffractive structure of the second region from the center point thereof is approximately equal to √

{square root over (2nλ

f)}.

10. The lens system of claim 9, wherein the second region provides a constant optical power.

11. The lens system of claim 7, wherein the second region is positioned radially interior to the first region.

12. The lens system of claim 7, wherein the radial widths of at least some of the surface relief diffractive structures of the first region are equal to one another.

15. The lens system of claim 7, wherein the lens system is dynamic.

16. The lens system of claim 15, wherein the lens system is electro-active.