Cylindrically segmented zone of focus artificial lens

• US 4,795,462 A
• Filed: 08/24/1987
• Issued: 01/03/1989
• Est. Priority Date: 08/24/1987
• Status: Expired due to Fees

• Current Assignee: Dennis T. Grendahl
• Original Assignee: Dennis T. Grendahl
• Inventors: Grendahl, Dennis T.
• Primary Examiner(s): Apley, Richard J.
• Assistant Examiner(s): Prizant, James
• Application Number:
  US07/088,413
• Time in Patent Office: 498 Days
• Field of Search: 623/6, 351/168, 351/171, 351/161, 351/162
• US Class Current: 623/6.28
• CPC Class Codes: A61F 2/1618 Multifocal lenses
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

An implantable or contact lens for replacement of a defective natural lens in an eye in which various annular portions of the lens have different powers and focal lengths to produce in-focus images, on different portions of the retina, of objects which are located at various distances from the eye, thereby substituting for the natural focusing action of the eye. The image processing capability of the brain functions to largely ignore the out of focus images and concentrate on the in focus image of the object selected by the brain for consideration.

Claims

1. A zone of focus lens for use with an eye comprising:

a. a cylindrical optical element;

b. at least one annular optical element joined and concentric with said cylindrical element to form a unitary lens structure having a front surface, a rear surface and a circular periphery;

c. each of said elements serving to create an image on distinct portions of the retina;

d. at least two of said elements having different powers whereby objects at different distances from the eye are simultaneously brought to a focus on distinct portions of the retina; and

,

e. at least two of said lens elements are different colors.

2. A lens according to claim 1 wherein at least two of said elements are of materials having different indices of refraction.

3. A lens according to claim 1 wherein at least two of said elements have different surface curvature.

4. A lens according to claim 3 further including a layer of transparent material overlying one of said front and rear surfaces to provide a smooth surface thereon.

5. A lens according to claim 3 further including first and second layers of transparent material overlying said front and rear surfaces, respectively, to provide smooth surfaces thereon.

6. A lens according to claim 1 wherein the boundaries between said elements include an anti-reflection material.

7. A lens according to claim 1 wherein the surface area of the boundaries between said elements are masked with an opaque material to block passage of rays which would otherwise cause reflections.

8. A lens according to claim 1 wherein said elements are joined with a transparent adhesive material.

9. A lens according to claim 8 wherein said adhesive material includes an anti-reflection additive.

10. A lens according to claim 1 wherein said elements are extrusion joined.

11. A lens according to claim 1 wherein adjacent ones of said elements have different indices of refraction.

12. A lens according to claim 1 comprised of elements each having different indices of refraction.

13. A lens according to claim 12 consisting of three elements.

14. A lens according to claim 11 having at least three elements.

15. A lens according to claim 1 wherein the front surface area of said annular element is greater than the front surface area of said cylindrical element.

16. A lens according to claim 1 wherein said elements providing sharp focus images of near objects are positioned within the inner half of the lens.

17. First and second lenses according to claim 1 for use in left and right eyes wherein like power elements are similarly positioned.

18. A lens according to claim 1 having a planar front surface and a convex rear surface to reduce internal reflections.

19. A lens according to claim 18 wherein the surface areas of the boundaries between said elements are masked with an opaque material to block passage of rays which would otherwise cause reflections.