Apparatus and methods for measuring accommodation of a lens in an eye

• US 20040041980A1
• Filed: 09/04/2002
• Published: 03/04/2004
• Est. Priority Date: 09/04/2002
• Status: Active Grant

• Current Assignee: Johnson & Johnson Surgical Vision, Inc. (Johnson & Johnson)
• Original Assignee: Advanced Medical Optics Incorporated (Johnson & Johnson)
• Inventors: Lang, Alan, Schier, Alan, Asa, Joseph, Laguette, Stephen
• Granted Patent: US 6,739,722 B2
• Time in Patent Office: Days
• US Class Current: 351/243
• CPC Class Codes: A61B 3/09 for testing accommodation
• CPC Class Codes: A61B 3/103 for determining refraction, e.g. refractometers, skiascopes

Abstract

Apparatus for measuring accommodation of a lens in an eye includes a target, a Badal lens, and a viewing aperture, where the Badal lens and the viewing aperture are positioned so that when the target moves towards or away from the lens, the apparent size of the target remains constant to a subject looking in the viewing aperture regardless of the distance the target moves. The apparatus may be provided in a compact housing and may include a mirror placed in the housing so that the viewing aperture can be placed away from the optical axis of the lens. The apparatus includes a controller to control the movement of the target. The apparatus measures the accommodation of a lens based on the distance the target moves during an examination. Methods of measuring accommodation of a lens in an eye of a subject are also disclosed.

Claims

1. Apparatus for measuring accommodation of a lens in an eye of a subject, comprising:

a housing;

a viewing target located in the housing on a track that permits the target to move in the housing;

a viewing aperture located in the housing to permit the subject to view the target; and

a lens located between the target and the viewing aperture at a position that provides a substantially constant apparent size of the target when viewed by the subject regardless of the distance between the target and the viewing aperture.

2. The apparatus of claim 1, which includes a single lens between the target and the viewing aperture.

3. The apparatus of claim 1, wherein the viewing target is a physical target.

4. The apparatus of claim 1, wherein the target includes an image provided on a slide.

5. The apparatus of claim 1, which further comprises an illumination source to illuminate the target.

6. The apparatus of claim 5, wherein the illumination source is movable with the target.

7. The apparatus of claim 5, wherein the target includes an image located between the illumination source and the lens, and a light transmitting background member located in proximity to the image.

8. The apparatus of claim 7, wherein the background member is located between the illumination source and the image.

9. The apparatus of claim 1, wherein the track includes a plurality of increments to permit the target to incrementally move along the track.

10. The apparatus of claim 1, further comprising a drive mechanism in communication with the target and the track to control the movement of the target along the track.

11. The apparatus of claim 1, wherein the viewing aperture is located near one end of the housing.

12. The apparatus of claim 1, further comprising a mirror located between the viewing aperture and the lens so that the target may be viewed by the subject when the viewing aperture is provided in the housing at a location that is not along an optical axis of the lens.

13. The apparatus of claim 1, wherein the target includes an image disposed on a light colored background member.

14. The apparatus of claim 13, wherein the image and the light colored background member are dimensioned to maintain a relatively constant pupil size of the subject while the subject is viewing the target as the target moves in the housing.

15. The apparatus of claim 1, further comprising at least one controller operatively coupled to the target to control movement of the target along the track.

16. The apparatus of claim 15, wherein the at least one controller is configured to control a rate at which the target moves along the track, and to control a brightness of the target.

17. The apparatus of claim 15, wherein the at least one controller includes a computer to determine the distance the target moves along the track.

18. The apparatus of claim 15, wherein the at least one controller is dimensioned to be held by the subject viewing the target.

19. The apparatus of claim 1, further comprising a computer operatively coupled to the target and being programmed to determine the amount of accommodation of a lens in the subject'"'"'s eye.

20. Apparatus for measuring accommodation of a lens in an eye of a subject, comprising:

a viewing aperture;

a physical target positioned on a track so that the target can move along the track toward or away from an eye of a subject viewing the target through the viewing aperture; and

a lens located in the apparatus so that when the physical target is viewed by the subject through the viewing aperture, the lens is positioned between the target and the subject'"'"'s eye, and the target has a substantially constant apparent size regardless of the distance between the target and the viewing aperture.

21. The apparatus of claim 20, which further comprises an illumination source to illuminate the target.

22. The apparatus of claim 21, wherein the physical target comprises an image having an opaque region and a transparent region, and the illumination source is positioned so that light provided by the illumination source passes through the transparent region.

23. The apparatus of claim 22, wherein the target further comprises a translucent member disposed between the illumination source and the image.

24. The apparatus of claim 20, further comprising a mirror located in the apparatus and positioned so that the subject may view the physical target without being located along a central optical axis of the lens.

25. The apparatus of claim 24, wherein the mirror is positioned so that the subject may view the physical target when positioned at an approximately ninety degree angle to the central optical axis of the lens.

26. The apparatus of claim 20, further comprising a computer operatively coupled to the target and programmed to monitor a distance over which the physical target moves and to calculate an accommodation amplitude based on the measured distance.

27. The apparatus of claim 20, further comprising a controller operatively coupled to the target to control movement of the physical target along the track.

28. Apparatus for measuring accommodation of a lens in an eye of a subject, comprising:

a target located in the apparatus and moveable towards or away from an eye of a subject when the subject is viewing the target, the target being structured to maintain a substantially constant pupil size of the eye as the target is moved towards or away from the eye.

29. The apparatus of claim 28, wherein the target includes an opaque portion occupying a minor portion of the area of the target, and a light transmitting portion occupying a major portion of the area of the target.

30. The apparatus of claim 29, wherein the opaque portion occupies about twenty percent or less of the area of the target.

31. The apparatus of claim 30, wherein the opaque portion occupies about ten percent or less of the area of the target.

32. The apparatus of claim 28, further comprising a lens disposed between the target and the eye of the subject when the subject is viewing the target, the lens being structured to maintain a substantially constant apparent size of the target as the target moves within the apparatus while being viewed by the subject.

33. The apparatus of claim 28, further comprising a computer operatively coupled to the target that is programmed to determine the accommodation of a lens in the eye of the subject by monitoring the distance the target moves when viewed by the subject, and calculating an accommodative amplitude based on the distance.

34. The apparatus of claim 28, further comprising a housing to contain the target.

35. A method for measuring accommodation of a lens in an eye of a subject, the method comprising steps of:

a) moving a target, which is structured to maintain a relatively constant pupil size in an eye of a subject viewing the target, from a first position towards or away from the subject'"'"'s eye to a second position;

b) determining the distance between the first position and the second position; and

c) determining an accommodative amplitude of the lens in the eye of the subject based on the distance determined in step (b).

36. The method of claim 35, wherein the step of moving the target is controlled by the subject viewing the target.

37. The method of claim 35, wherein steps (a), (b), and (c) are controlled by the subject viewing the target without assistance of another person.

38. The method of claim 35, wherein the first position of the target provides a relatively focused image of the target as perceived by the subject, and the second position of the target provides a relatively blurred image of the target as perceived by the subject.

39. The method of claim 35, wherein the first position of the target provides a relatively blurred image of the target as perceived by the subject, and the second position of the target provides a relatively focused image of the target as perceived by the subject.

40. The method of claim 35, further comprising a step of:

illuminating an image provided on the target, the image being opaque and occupying a minor portion of the area of the target.

41. A method for measuring accommodation of an intraocular lens implanted in an eye of a subject, the method comprising steps of:

a) moving a target, which is structured to maintain a relatively constant pupil size in an eye of a subject viewing the target, from a first position towards or away from the subject'"'"'s eye to a second position;

b) determining the distance between the first position and the second position; and

c) determining an accommodative amplitude of the intraocular lens implanted in the eye of the subject based on the distance determined in step (b).

42. The method of claim 41, further comprising a step of determining if the accommodative amplitude is sufficient to improve vision of the subject.

43. The method of claim 41, wherein the method is performed to compare accommodative abilities of a plurality of intraocular lens implanted in an eye, each intraocular lens implanted at separate times into the eye.