Radially segmented zone of focus artificial lens

• US 4,798,609 A
• Filed: 08/24/1987
• Issued: 01/17/1989
• 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:
  US07/088,249
• Time in Patent Office: 512 Days
• Field of Search: 623/6, 351/168, 351/171, 351/161, 351/162
• US Class Current: 623/6.29
• CPC Class Codes: A61F 2/1618 Multifocal lenses
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: G02C 7/042 Simultaneous type
• CPC Class Codes: G02C 7/045 Sectorial configuration
• CPC Class Codes: G02C 7/105 having inhomogeneously distributed colouring

Abstract

An implantable or contact lens for replacement of a defective natural lens in an eye in which various portions of the lens have different powers and focal lenghts 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 plurality of pie-shaped optical elements joined at the sides to form a unitary lens structure having a front surface, a rear surface and a circular periphery;

b. each of said pie-shaped elements serving to create an image on a distinct portion of the retina;

c. 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

d. at least two of said pie-shaped optical elements are of different colors.

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

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

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

5. A lens according to claim 1 wherein the boundaries between said pie-shaped elements include an anti-reflective material.

6. A lens according to claim 1 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.

7. A lens according to claim 1 wherein said pie-shaped elements are joined with a transparent adhesive material.

8. A lens according to claim 1 wherein said pie-shaped elements are joined during an extrusion process.

9. A lens according to claim 1 wherein adjacent of said pie-shaped elements have different indices of refraction.

10. A lens according to claim 9 comprised of first and second elements having first and second indices of refraction.

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

12. A lens according to claim 11 consisting of three elements.

13. A lens according to claim 9 having at least three elements.

14. A lens according to claim 1 wherein pie-shaped elements of like index of refraction are positioned diametrically opposite in said lens.

15. A lens according to claim 1 wherein said pie-shaped elements providing sharp focus images of near objects are positioned horizontally across said lens.

16. A lens according to claim 1 wherein said pie-shaped elements providing sharp focus images of far objects are positioned vertically across said lens.

17. A lens according to claim 1 wherein said pie-shaped elements providing sharp focus images of near objects are positioned within the lower half of said lens.

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