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DE-112023004054-B4 - Contact lenses and related procedures

DE112023004054B4DE 112023004054 B4DE112023004054 B4DE 112023004054B4DE-112023004054-B4

Abstract

Contact lens (301, 401, 501), wherein the lens (301, 401, 501) has an optical zone (302, 402, 502) comprising: a central region (305, 405, 505), wherein the central region (305, 405, 505) has a first optical axis (319, 419, 519), a center of curvature with base refractive power lying on the first optical axis (319, 419, 519), and a diameter of less than 2.0 mm; and a ring region (303, 403, 503) comprising a plurality of concentric treatment zones (303a, 303b, 403a, 403b, 503a, 503b) that are adjacent to each other, each treatment zone (303a, 303b, 403a, 403b, 503a, 503b) having a radial sagittal refractive power profile (331, 431, 531) that increases with increasing radial distance from the optical axis (319, 419, 519).

Inventors

  • Martin WEBBER
  • Paul Chamberlain
  • Baskar ARUMUGAM
  • Arthur Bradley

Assignees

  • COOPERVISION INTERNATIONAL LIMITED

Dates

Publication Date
20260513
Application Date
20230929
Priority Date
20220929

Claims (20)

  1. Contact lens (301, 401, 501), wherein the lens (301, 401, 501) has an optical zone (302, 402, 502) comprising: a central area (305, 405, 505), wherein the central area (305, 405, 505) has a first optical axis (319, 419, 519), a center of curvature with base refractive power lying on the first optical axis (319, 419, 519), and a diameter of less than 2.0 mm; and a ring region (303, 403, 503) comprising a plurality of concentric treatment zones (303a, 303b, 403a, 403b, 503a, 503b) adjacent to each other, each treatment zone (303a, 303b, 403a, 403b, 503a, 503b) having a radial sagittal refractive power profile (331, 431, 531) that increases with increasing radial distance from the optical axis (319, 419, 519).
  2. Contact lens (301, 401, 501) according to Claim 1 , wherein at least two of the treatment zones (303a, 303b, 403a, 403b, 503a, 503b) have different radial sagittal refractive power profiles (331, 431, 531).
  3. Contact lens (301, 401, 501) according to Claim 1 or Claim 2 , wherein the ring area (305, 405, 505) has between 2 and 10 concentric treatment zones (303a, 303b, 403a, 403b, 503a, 503b).
  4. Contact lens (301, 401, 501) according to one of the preceding claims, wherein each of the plurality of concentric treatment zones (303a, 303b, 403a, 403b, 503a, 503b) has a different ches radial sagittal refractive power profile (331, 431, 531) has.
  5. Contact lens (301, 401, 501) according to one of the preceding claims, wherein each treatment zone (303a, 303b, 403a, 403b, 503a, 503b) has a radial width between 0.1 and 2.5 mm.
  6. Contact lens (301, 401, 501) according to one of the preceding claims, wherein each treatment zone (303a, 303b, 403a, 403b, 503a, 503b) has a radial sagittal refractive power gradient (331, 431, 531) between 0.5 D/mm and 20.0 D/mm.
  7. Contact lens (301, 401, 501) according to one of the preceding claims, having a nominal distance refractive power between + 0.5 D and -15.0 D.
  8. Contact lens (301, 401, 501) according to Claim 7 , wherein at least one treatment zone (303a, 303b, 403a, 403b, 503a, 503b) has a radial curvature refractive power (332, 432, 532) that is greater than the nominal distance refractive power of the lens (301, 401, 501).
  9. Contact lens (301, 401, 501) according to Claim 7 , wherein each treatment zone (303a, 303b, 403a, 403b, 503a, 503b) has a radial curvature refractive power (332, 432, 532) that is greater than the nominal distance refractive power of the lens (301, 401, 501).
  10. Contact lens (301, 401, 501) according to one of the preceding claims, wherein the radial curvature refractive power (332, 432, 532) of the central region (305, 405, 505) is equal to the nominal distance refractive power.
  11. Contact lens (301, 401, 501) according to one of the Claims 1 until 9 , wherein the nominal distance refractive power of the lens (301, 401, 501) is greater than the radial curvature refractive power (332, 432, 532) of the central region (305, 405, 505).
  12. Contact lens (301, 401, 501) according to one of the Claims 7 until 8 or 10 until 11 , wherein alternating concentric treatment zones provide higher radial curvature refractive powers and lower radial curvature refractive powers, the higher radial curvature refractive power being greater than the nominal distance refractive power of the lens (301, 401, 501).
  13. Contact lens (301, 401, 501) according to Claim 12 , where the lower radial curvature addition value is greater than the nominal refractive power of the lens (301, 401, 501).
  14. Contact lens (301, 401, 501) according to one of the Claims 7 until 10 or after Claim 12 , wherein each treatment zone (303a, 303b, 403a, 403b, 503a, 503b) has a radial curvature addition value (332, 432, 532) between +2.0 D and 10.0 D.
  15. Contact lens (301, 401, 501) according to one of the preceding claims, wherein at a point in the middle of the radial width of an innermost of the treatment zones (303a, 403a, 503a) the radial sagittal refractive power (331, 431, 531) of this treatment zone (303a, 403a, 503a) corresponds to the nominal distance refractive power of the lens (301, 401, 501).
  16. Contact lens (301, 401, 501) according to Claim 15 , wherein at a point in the middle of the radial width of each treatment zone (303a, 303b, 403a, 403b, 503a, 503b) the radial sagittal refractive power (331, 431, 531) of that treatment zone corresponds to the nominal distance refractive power of the lens (301, 401, 501).
  17. Contact lens (301, 401, 501) according to one of the Claims 1 until 15 , wherein at least one treatment zone (303a, 303b, 403a, 403b, 503a, 503b) is a sagittal addition treatment zone having a radial sagittal refractive power (331, 431, 531) that is greater than the nominal distance refractive power of the lens (301, 401, 501) across the width of that treatment zone.
  18. Contact lens (301, 401, 501) according to one of the preceding claims, wherein the radial sagittal refractive power profile (331, 431, 531) is approximately flat in the central region (305, 405, 505).
  19. Contact lens (301, 401, 501) according to one of the preceding claims, wherein the radial sagittal refractive power profile (331, 431, 531) is curved in the central region (305, 405, 505).
  20. Contact lens (301, 401, 501) according to 19, wherein the radial sagittal refractive power profile (331, 431, 531) in the central region (305, 405, 505) has a square or parabolic shape.

Description

Technical field The present invention relates to contact lenses. In particular, but not exclusively, the present invention relates to contact lenses for slowing the progression of myopia. The present invention also relates in particular, but not exclusively, to contact lenses for use by people with presbyopia. The present invention also relates to methods for manufacturing such lenses. background Many people, including children and adults, need contact lenses to correct myopia (nearsightedness), and many adults need lenses to correct presbyopia (age-related inability to accommodate and therefore inability to focus on near objects). Uncorrected myopic eyes focus light from distant objects onto a point in front of the retina. Consequently, the light converges in a plane in front of the retina and diverges towards the retina, where it becomes blurred upon arrival. Conventional lenses (e.g., spectacle lenses and contact lenses) used to correct myopia reduce the convergence (in the case of contact lenses) or cause divergence (in the case of spectacle lenses) of the incoming light from distant objects before it reaches the eye, thus shifting the focal point onto the retina. The inner lenses of presbyopic eyes do not change their shape to provide the refractive power needed to focus on near objects. Conventional lenses (e.g., eyeglasses and contact lenses) for correcting presbyopia provide the missing additional refractive power in the form of bifocal or progressive lenses, which have areas optimized for near vision and areas optimized for distance vision. Presbyopia can also be treated with bifocal or multifocal lenses, or with monovision lenses (where each eye has a different prescription, with one eye wearing a distance lens and the other a near lens). Several decades ago, it was suggested that the progression of myopia in children and adolescents could be slowed or prevented by undercorrection, i.e., by shifting the focal point toward the retina, but not entirely onto it. However, this approach inevitably leads to a deterioration of distance vision compared to a lens that fully corrects the myopia. Furthermore, it is now considered doubtful that undercorrection can effectively combat developing myopia. A more recent approach to correcting myopia involves using lenses that have one or more areas that provide full correction for distance vision, as well as one or more areas that undercorrect or intentionally induce myopic defocusing. This approach is thought to prevent or slow the development or progression of myopia in children and adolescents while ensuring good distance vision. In the case of lenses with areas that provide defocusing, the areas that fully correct distance vision are usually called base refractive power areas, and the areas that undercorrect or intentionally induce myopic defocusing are usually called myopic defocusing areas or addition refractive power areas (because the dioptric power is more positive or less negative than the refractive power of the distance areas). One surface (usually the front surface) of the addition area(s) has a smaller radius of curvature than that of the distance area(s) and therefore provides a more positive or less negative refractive power to the eye. The addition area(s) are designed to focus parallel incident light (i.e., light from a distance) in front of the retina (i.e., closer to the lens), while the distance refractive power area(s) are designed to focus the light and form an image on the retina (i.e., farther from the lens). A well-known type of contact lens that slows the progression of myopia is a dual-focus contact lens, available under the name MISIGHT (CooperVision, Inc.). This dual-focus lens differs from bifocal or multifocal contact lenses configured to improve the vision of presbyopic individuals in that it has specific optical dimensions that allow a person capable of accommodation to utilize the distance correction (i.e., the base refractive power) for viewing both distant and near objects. The treatment zones of the dual-focus lens, which provide the addition refractive power, also deliver a myopically defocused image at both near and far distances. While these lenses have proven beneficial in preventing or slowing the development or progression of myopia, ring-shaped addition refractive power zones can cause undesirable visual side effects. Light focused by the ring-shaped addition refractive power zones in front of the retina, The light deviates from the focal point and forms a defocused ring on the retina. Wearers of these lenses may therefore see a ring or "halo" around the images that form on the retina, especially with small, bright objects such as streetlights and car headlights. Instead of using the eye's natural accommodation (i.e., its natural ability to change focal length) to focus on nearby objects, wearers can theoretically use the additional focus in front of the retina, resulting from the ring-shaped area of added refractive po