MULTI-LENS SYSTEM FOR PRESBYOPIA
20210325694 · 2021-10-21
Inventors
Cpc classification
G02C7/047
PHYSICS
International classification
Abstract
Described herein are systems and/or methods for designing a system of contact lenses with interocular refractive disparity (i.e. anisometropia) for presbyopes. An example method may comprise a step of determining a plurality of lenses for inclusion in a system of contact lenses for treating presbyopes. Each of the plurality of lenses may be configured for an optical correction and may have a power profile associated therewith. The plurality of lenses may be grouped based on the optical correction. Each of the lenses in a particular group may have a different power profile. The example method may comprise a step of creating, based at least on the plurality of lenses and an add need, a fit guide. The fit guide may provide an interocular disparity of effective add. The interocular disparity of effective add may be determined by optimizing cyclopean performance across a range accommodative demands and light levels.
Claims
1. A method for designing a system of contact lenses with interocular refractive disparity for presbyopes, the method comprising the steps of: determining a plurality of lens types for inclusion in a system of contact lenses for treating presbyopes, wherein the lens system comprises at least three lens types (lens A, a lens B, and a lens C designation), wherein each of the plurality of lenses is configured for an optical correction and has a power profile associated therewith, wherein the plurality of lenses are grouped based on the optical correction and wherein each of the lenses of a particular type has a different power profile, and wherein the optical correction normalized power profile across a range of optical corrections for each of the lens designations is varied to improve performance based on at least [1] prescription (Rx), age and accommodation dependence of ocular spherical aberration, or [2] Rx, age, and luminance dependence of entrance pupil diameter; and creating, based at least on the plurality of lenses and an add need, a fit guide indicating which of the plurality of lenses to be worn on a dominant eye and a non-dominant eye, wherein the fit guide provides an interocular disparity of effective add.
2. The method of claim 1, wherein each lens group comprises at least three center-near continuous multifocal lenses.
3. The method of claim 1, wherein each group of lenses comprises three lenses.
4. The method of claim 1, wherein each group of lenses comprises four lenses.
5. The method of claim 1, wherein each group of lenses comprises five lenses.
6. The method of claim 1, wherein the optical correction is between −20 D and +20 D.
7. The method of claim 1, wherein determining a plurality of lens groups comprises determining a visual performance manifold for one or more of the lenses in the plurality of lens groups.
8. The method of claim 1, wherein the fit guide comprises one or more of: TABLE-US-00012 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25 +0.25 +0.25 +0.25 TABLE-US-00013 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D TABLE-US-00014 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensB lensB lensB lensB lensB Dominant −0.25D −0.25D −0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00015 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00016 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensA lensA lensA lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D −0.25D −0.25D TABLE-US-00017 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensB lensB lensB lensC lensC lensC lensC lensC −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D
9. A system of contact lenses with interocular disparity for presbyopes, the system comprising: a plurality of lens types for treating presbyopes, wherein the lens system comprises at least three lens types (lens A, a lens B, and a lens C designation), wherein each of the plurality of lenses is configured for an optical correction and has a power profile associated therewith, wherein the plurality of lenses are grouped based on the optical correction and wherein each of the lenses of a particular type has a different power profile, and wherein the optical correction normalized power profile across a range of optical corrections for each of the lens designations is varied to improve performance based on at least [1] prescription (Rx), age and accommodation dependence of ocular spherical aberration, [2] Rx, age, and luminance dependence of entrance pupil diameter; and a fit guide indicating which of the plurality of lenses to be worn on a dominant eye and a non-dominant eye, wherein the fit guide provides an interocular disparity of effective add.
10. The system of claim 9, wherein each lens group comprises at least three center near continuous multifocal lenses.
11. The system of claim 9, wherein each group of lenses comprises three lenses.
12. The system of claim 9, wherein each group of lenses comprises four lenses.
13. The system of claim 9, wherein each group of lenses comprises five lenses.
14. The system of claim 9, wherein the power profile is between −20 D and +20 D.
15. The system of claim 9, wherein the fit guide is dependent on a visual performance manifold for one or more of the lenses in the plurality of lens groups.
16. The method of claim 9, wherein the fit guide comprises one or more of: TABLE-US-00018 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25 +0.25 +0.25 +0.25 TABLE-US-00019 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D TABLE-US-00020 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensB lensB lensB lensB lensB Dominant −0.25D −0.25D −0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00021 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00022 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensA lensA lensA lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D −0.25D −0.25D TABLE-US-00023 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensB lensB lensB lensC lensC lensC lensC lensC −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D
17. A method for designing a system of contact lenses with interocular refractive disparity for presbyopes, the method comprising the steps of: determining a plurality of lenses for inclusion in a system of contact lenses for treating presbyopes, wherein each of the plurality of lenses is configured for an optical correction and has a power profile associated therewith, wherein the plurality of lenses are grouped based on the optical correction and wherein each of the lenses in a particular group has a different power profile; and creating, based at least on the plurality of lenses and an add need, a fit guide indicating which of the plurality of lenses to be worn on a dominant eye and a non-dominant eye, wherein the fit guide provides an interocular disparity of effective add.
18. The method of claim 17, wherein each group of lenses comprises three lenses.
19. The method of claim 17, wherein each group of lenses comprises four lenses.
20. The method of claim 17, wherein each group of lenses comprises five lenses.
21. The method of claim 17, wherein the power profile is between −20 D and +20 D.
22. The method of claim 17, wherein determining a plurality of lenses comprises determining a visual performance manifold for one or more of the lenses.
23. The method of claim 17, wherein the fit guide comprises one or more of: TABLE-US-00024 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25 +0.25 +0.25 +0.25 TABLE-US-00025 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D TABLE-US-00026 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensB lensB lensB lensB lensB Dominant −0.25D −0.25D −0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00027 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00028 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensA lensA lensA lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D −0.25D −0.25D TABLE-US-00029 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensB lensB lensB lensC lensC lensC lensC lensC −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D
24. A method for customizing a system of contact lenses with interocular refractive disparity for presbyopes, the method comprising the steps of: determining a fit associated with at least one user exhibiting presbyopia; simulating, based on the fit, one or more visual performance manifolds, wherein each of the visual performance manifolds is generated based on lens designs, an eye model, and environmental conditions; selecting, based on the simulated one or more visual performance manifolds, a plurality of lenses for inclusion in a system of contact lenses for treating presbyopia, wherein each of the plurality of lenses is configured for an optical correction and has a power profile associated therewith, wherein the plurality of lenses are grouped based on the optical correction and wherein each of the lenses in a particular group has a different power profile; and creating, based at least on the plurality of lenses and an add need, a fit guide indicating which of the plurality of lenses to be worn on a dominant eye and a non-dominant eye, wherein the fit guide provides an interocular disparity of effective add.
25. The method of claim 24, wherein each group of lenses comprises three lenses.
26. The method of claim 24, wherein each group of lenses comprises four lenses.
27. The method of claim 24, wherein each group of lenses comprises five lenses.
28. The method of claim 24, wherein the optical power is between −20 D and +20 D.
29. The method of claim 24, wherein determining a fit profile comprises optimizing a treatment plan for the particular user.
30. The method of claim 29, wherein the optimizing comprises using one or more visual performance manifolds.
31. The method of claim 24, wherein the fit guide comprises one or more of: TABLE-US-00030 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25 +0.25 +0.25 +0.25 TABLE-US-00031 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D TABLE-US-00032 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensB lensB lensB lensB lensB Dominant −0.25D −0.25D −0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00033 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D +0.25D +0.25D +0.50D +0.50D +0.50D TABLE-US-00034 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensA lensA lensA lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D −0.25D −0.25D TABLE-US-00035 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensB lensB lensB lensC lensC lensC lensC lensC −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The following drawings show generally, by way of example, but not by way of limitation, various examples discussed in the present disclosure. In the drawings:
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DETAILED DESCRIPTION
[0048] Described herein are systems and/or methods for customizing a system of contact lenses with interocular disparity for presbyopes. An example method may comprise a step of determining a fit associated with at least one user exhibiting presbyopia. Determining a fit may comprise optimizing a treatment plan for the particular user. Optimizing may comprise using one or more visual performance manifolds, as shown and described herein.
[0049] Described herein are systems and/or methods for designing and implementing a system of contact lenses with interocular disparity for presbyopes. An example system may comprise a plurality of lens types for treating presbyopes. The lens system may comprise at least three lens types (lens A, a lens B, and a lens C designation). The lens types may vary by one or more of effective add or DOF. Each of the plurality of lenses may be configured for an optical correction and may have a power profile associated therewith. The plurality of lenses may be grouped based on the optical correction. Each of the lenses of a particular type may have a different power profile. The optical correction normalized power profile across a range of optical corrections for each of the lens designations may be varied to improve performance considering [1] prescription (Rx), age and accommodation dependence of ocular spherical aberration, [2] Rx, age and luminance dependence of entrance pupil diameter.
[0050] The example method may comprise selecting a fit associated with at least one user exhibiting presbyopia. The method may comprise simulating, based on the fit profile, one or more visual performance manifolds, wherein each of the visual performance manifolds is generated based on lens designs, an eye model, and environmental conditions. The method may comprise selecting, based on the selected one or more visual performance manifolds, a plurality of lenses for inclusion in a system of contact lenses for treating presbyopia, or for alterations in lens fit given the visual performance achieved, wherein each of the plurality of lenses is configured for an optical correction and has a power profile associated therewith, wherein the plurality of lenses are grouped based on the optical correction and wherein each of the lenses in a particular group has a different power profile. The method may comprise creating, based at least on the plurality of lenses and an add need, a fit guide indicating which of the plurality of lenses to be worn on a dominant eye and a non-dominant eye, wherein the fit guide provides an interocular disparity of effective add.
[0051] An example method may comprise a step of determining a plurality of lens types for inclusion in a system of contact lenses for treating presbyopes. The lens system may comprise at least three lens types (lens A, a lens B, and a lens C designation). Although other groupings and numbers of lens types may be used. Each of the plurality of lenses may be configured for an optical correction and may have a power profile associated therewith. The plurality of lenses may be grouped based on the optical correction. Each lens group may comprise at least three center-near continuous multifocal lenses. Each group of lenses may comprise three lenses. Each group of lenses may comprise four lenses. Each group of lenses may comprise five lenses. The power profile may be between −20 D and +20 D. Determining a plurality of lens groups may comprise determining a visual performance manifold for one or more of the lenses in the plurality of lens groups.
[0052] Each of the lenses of a particular type may have a different power profile. However, the optical correction normalized power profile across a range of optical corrections for each of the lens designations may be varied to improve performance considering prescription (Rx) and accommodation dependence of ocular spherical aberration and Rx, age and luminance dependence of entrance pupil diameter. In other words, a variation of the normalized power profile across SKU (e.g., optical correction levels) may be increased compared to variation in conventional lenses or lens systems. The disclosed lens systems and methods permit a superior trade-off regarding overall through focus visual performance over conventional lenses and lens systems. As an illustrative example, such performance improvement may be achieved by leveraging the capacity of the visual system to tolerate interocular refractive disparity to further increase the cyclopean depth of focus (DOF). Additionally or alternatively, the disclosed lens designs employ more add power, more variation in design across SKU, and a visual performance manifold optimized fit/refit prescription, as compared to conventional lenses or lens systems.
[0053] A fit guide may be created and/or used. The fit guide may be created based at least on the plurality of lenses and an add need. The fit guide may be customized for a user or users. Various fit guides may be created and compared for optimal performance for a user or users. A fit guide may indicate which of the plurality of lenses to be worn on a dominant eye and a non-dominant eye. An example fit guide may comprise one or more of the following example fit guides. Although designations for a particular fit guide application is shown, this is for illustration and should not necessarily be limited, as such.
[0054] Initial Lens Selection:
TABLE-US-00001 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D
[0055] Lens change if required for distance complaint:
TABLE-US-00002 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensB lensB lensB lensB lensB Dominant −0.25D −0.25D −0.25D +0.25D +0.25D +0.50D +0.50D +0.50D
[0056] Lens change if required for near complaint:
TABLE-US-00003 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D +0.25D +0.25D +0.50D +0.50D +0.50D
[0057] Lens change if required for second distance complaint:
TABLE-US-00004 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensA lensA lensA lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D −0.25D −0.25D
[0058] Lens change if required for second near complaint:
TABLE-US-00005 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensB lensB lensB lensC lensC lensC lensC lensC −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D −0.25D Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25D +0.25D +0.25D
[0059] The fit guide or guides may provide an interocular disparity of effective add.
[0060] DOF is a 3-line drop from peak performance. The plot in
[0061] As a comparison, the following tables show effective add for a conventional MF lens system and a lens system in accordance with the present disclosure.
[0062] Effective Add Tables
TABLE-US-00006 MF, Rx = −3 D Effective Effective Effective Add @ 2.5 Add @ 120 Add @ 400 Lens cd/m.sup.2 cd/m.sup.2 cd/m.sup.2 Lens A 0.25 D 0.30 D 0.30 D Lens B 0.60 D 0.85 D 0.90 D Lens C 0.80 D 1.25 D 1.40 D
TABLE-US-00007 Lens Fit (MF, Rx = −3 D) Add Need Eye 0.75 D 1.00 D 1.25 D 1.50 D 1.75 D 2.00 D 2.25 D 2.50 D Dom A A A B B B B B Non A A A B B C C C Interocular Disparity of Effective Add Add Need Luminance 0.75 D 1.00 D 1.25 D 1.50 D 1.75 D 2.00 D 2.25 D 2.50 D 2.5 cd/m.sup.2 0.00 D 0.00 D 0.00 D 0.00 D 0.00 D 0.20 D 0.20 D 0.20 D 120 cd/m.sup.2 0.00 D 0.00 D 0.00 D 0.00 D 0.00 D 0.40 D 0.40 D 0.40 D 400 cd/m.sup.2 0.00 D 0.00 D 0.00 D 0.00 D 0.00 D 0.50 D 0.50 D 0.50 D
TABLE-US-00008 New Optic, Rx = −3 D Effective Effective Effective Add @ 2.5 Add @ 120 Add @ 400 Lens cd/m.sup.2 cd/m.sup.2 cd/m.sup.2 Lens A 0.05 D 0.10 D 0.10 D Lens B 0.25 D 0.70 D 0.75 D Lens C 1.00 D 1.15 D 1.15 D Lens C+ 1.25 D 1.40 D 1.40 D
TABLE-US-00009 Lens Fit (New Optic, Rx = −3 D) Add Need Eye 0.75 D 1.00 D 1.25 D 1.50 D 1.75 D 2.00 D 2.25 D 2.50 D Dom A A A B B B B B Non B B B C C C+ C+ C+ Interocular Disparity of Effective Add Add Need Luminance 0.75 D 1.00 D 1.25 D 1.50 D 1.75 D 2.00 D 2.25 D 2.50 D 2.5 cd/m.sup.2 0.20 D 0.20 D 0.20 D 0.75 D 0.75 D 1.00 D 1.00 D 1.00 D 120 cd/m.sup.2 0.60 D 0.60 D 0.60 D 0.45 D 0.45 D 0.70 D 0.70 D 0.70 D 400 cd/m.sup.2 0.65 D 0.65 D 0.65 D 0.40 D 0.40 D 0.65 D 0.65 D 0.65 D
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[0064] As a further example, fit guides may be based on one or more visual performance manifolds. As such, a fit guide may be customized for a user or group of users based on comparative testing or optimizing visual performance manifolds for the user or users.
[0065] As an illustrative example, lens design optimization procedure may be based on visual performance. A metric of monocular visual performance is given by:
φ.sub.eye=∫MTF(ν).sup.2NCSF(ν).sup.2dν
[0066] where MTF is the modulation transfer function of the lens+eye combination, NCSF is the neural contrast sensitivity function for a given pupil size and luminance and ν is spatial frequency.
[0067] Binocular visual performance is obtained using a vectorial model:
Φ.sub.bin√{square root over ((φ.sub.dom.sup.2+φ.sub.non.sup.2−αφ.sub.domφ.sub.non)}
[0068] where the subscripts dom and non refer to the dominant and nondominant eye, respectively, and α is a constant.
[0069] Optimization of visual performance is obtained across a range of eye models (spanning the age and add need range typical of a presbyopic population) by minimization:
min Σφ.sub.ideal−φ.sub.bin]
[0070] where ψ.sub.ideal is obtained using diffraction limited binocular visual performance.
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[0079] As illustrated, simulations indicate that the example lens system of the present disclosure provides comparable or superior distance and near performance and sacrifices a bit of intermediate performance in low light when compared to MF. In general, the example lens system of the present disclosure uses more effective add and provides more DOF in the non-dominant eye, while MF uses more effective add and the example lens system of the present disclosure provides more DOF in the dominant eye. However, in bright conditions where the pupil is small, cyclopean DOF with both designs are equivalent. Although the increased DOF of the example lens system of the present disclosure may be significant in low light conditions, the predominant difference between the two systems (from dim to bright light) is due to differences in the effective add. Therefore, the example lens system of the present disclosure improves through-focus cyclopean visual performance by optimally leveraging the visual system's tolerance of interocular disparity of effective add.
EXAMPLES
[0080] Power Profiles and Visual Performance Manifolds
[0081] For each design simulated, the power profiles of each lens in the lens system were plotted for refractive errors of −9, −6, −3, 2, 4 and 6 D, and the visual performance manifold is presented. The fit guide is presented in tabular form for each design. The fit guide includes information about the lens design and the fit for both the dominant and non-dominant eyes. The fit is the difference between the power label of the fitted lens and the subject's refraction. Visual performance is gray-level coded in units of −10 log MAR from −2 to 0.5. Values above 0.5 saturate and remain dark gray while values below −2 saturate and are displayed as white.
[0082] Multifocal (MF)
TABLE-US-00010 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB (MF_A) (MF_A) (MF_A) (MF_B) (MF_B) (MF_B) (MF_B) (MF_B) Non- lensA lensA lensA lensB lensB lensC lensC lensC Dominant (MF_A) (MF_A) (MF_A) (MF_B) (MF_B) (MF_C) (MF_C) (MF_C)
[0083] Example Lens System of the Present Disclosure
TABLE-US-00011 Add Need (D) 0.75 1 1.25 1.5 1.75 2 2.25 2.5 Dominant lensA lensA lensA lensB lensB lensB lensB lensB Non- lensB lensB lensB lensC lensC lensC lensC lensC Dominant +0.25 +0.25 +0.25 +0.25
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[0093] Although shown and described in what is believed to be the most practical and preferred embodiments, it is apparent that departures from specific designs and methods described and shown will suggest themselves to those skilled in the art and may be used without departing from the spirit and scope of the disclosure. The present disclosure is not restricted to the particular constructions described and illustrated but should be constructed to cohere with all modifications that may fall within the scope of the appended claims.