US5220359A
Expired / Lapsed
US
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Lens design method and resulting aspheric lens
Assignee: Johnson and Johnson Vision Care Inc
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Filing: 1991-07-11
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Granted: 1993-06-15
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Expires: 2011-07-11
Abstract
Abstract An aspheric lens for providing improved vision and a method for generating such a lens is described. The lens provides a sharp image focus while minimizing image aberrations. The method utilizes ray tracing techniques in conjunction with Modulation Transfer functions to accurately account for the total corrective lens-eye system. The lens may be in the form of a contact lens, an intraocular lens, a natural lens or a spectacle lens, and is suitable for correcting myopia, presbyopia, astigmatism and other focusing problems. The lens is characterized by a hyperbolic or parabolic surface which functions to reduce spherical aberrations and minimize the retinal image spot size.
Inventors
- 👤 Jeffrey H. Roffman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 08:58
CPC Classifications
G; G02; G02C; G02C7/00; G02C7/02; G02C7/024; G02C7/028; G02C7/04; G02C2202/00; G02C2202/20
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
140 words
A method of constructing a lens for focusing light on the retina of the eye comprising the steps of: a) constructing a Fourier Transform function model that generates modulation transfer frequencies for the human eye and a preliminary lens, said lens having at least one rotationally symmetric surface defined by the equation: ##EQU4## where X is the aspheric surface point at position Y, r is the central radius, and κ is commonly used aspheric constant, wherein the value of κ is between -0.5 and -1, b) performing an analysis using the model so constructed to trace light ray paths through the lens-eye system, c) varying the value of the aspheric constant, κ, for the preliminary lens to achieve a lens-eye system with a trace of light ray paths optimized for sharpest focus by minimizing retinal spot size of said rays.
Claim 2
Independent Claim
140 words
A method of constructing a lens for focusing light on the retina of the eye comprising the steps of: a) constructing a Fourier Transform function model that generates modulation transfer frequencies for the human eye and a preliminary lens, said lens having at least one rotationally symmetric surface defined by the equation: ##EQU4## where X is the aspheric surface point at position Y, r is the central radius, and κ is commonly used aspheric constant, wherein the value of κ is between -0.5 and -1, b) performing an analysis using the model so constructed to trace light ray paths through the lens-eye system, c) varying the value of the aspheric constant, κ, for the preliminary lens to achieve a lens-eye system with a trace of light ray paths optimized for sharpest focus by minimizing retinal spot size of said rays.
Claim 3
Dependent Claim
14 words
The method of claim 1 wherein the lens so constructed is a contact lens.
Claim 4
Dependent Claim
22 words
The method of claim 1 wherein the modulation transfer frequency is compared to the diffraction limit to optimize the corrective lens-eye system.
Claim 5
Dependent Claim
28 words
The method of claim 1 wherein the eye in the corrective lens-eye system is emmetropic and the optimization process produces vision that exceeds that of the normal eye.
Claim 6
Dependent Claim
21 words
The method of claim 1 wherein the corrective lens-eye system is optimized by positioning the focused image closest to the retina.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-06-14 | 1996-12-14 | 1997-06-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-14 | 2000-12-14 | 2001-06-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-14 | 2004-12-14 | 2005-06-15 | $7700.00 | Window Closed / Lapsed |