Patent US5344447A successfully refreshed from Google Patents.
US5344447A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Diffractive trifocal intra-ocular lens design
Assignee: Massachusetts Institute of Technology
•
Filing: 1992-11-12
•
Granted: 1994-09-06
•
Expires: 2012-11-12
Abstract
Abstract An intraocular lens including a refractive/diffractive lens having an anterior surface and a posterior surface and a generally anterior posterior optical axis. At least one of the surfaces has a diffractive lens profile that is binary in phase, and produces three useful focal points. The diffractive lens profile is designed to provide three foci each containing 28.8% of the incident light, with the residual 14% of the light going into other foci. Additionally, some of the out-of-focus light of this design contributes positively to the image, and the resultant maximum image contrast is above 28.8%. This design adds clear mid-range vision, at the expense of a slight decrease in near and far vision, and the added mid-range vision makes the device less sensitive to longitudinal placement in the eye.
Inventors
- 👤 Gary J. Swanson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:12
CPC Classifications
A; A61; A61F; A61F2/00; A61F2/02; A61F2/14; A61F2/16; A61F2/1602; A61F2/161; G; G02; G02B; G02B5/00; G02B5/18; G02B5/1876; A61F2/1613; A61F2/1616; A61F2/1618; A61F2/1654; G02B5/189; G02B5/1895
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
116 words
An intraocular optical lens comprising a refractive component on an anterior surface of the lens, and a completely transparent diffractive component on a posterior surface of the lens, and a generally anterior-posterior optical axis, the diffractive component having a zero order, a negative first order, and a positive first order, the refractive component combined with the positive first order of the diffractive component adapted to focus the incident light on the lens for near vision, the refractive component adapted to focus the incident light on the lens for mid-range vision, and the refractive component combined with the negative first order of the diffractive component adapted to focus the incident light on the lens for far vision.
Claim 2
Dependent Claim
116 words
An intraocular optical lens comprising a refractive component on an anterior surface of the lens, and a completely transparent diffractive component on a posterior surface of the lens, and a generally anterior-posterior optical axis, the diffractive component having a zero order, a negative first order, and a positive first order, the refractive component combined with the positive first order of the diffractive component adapted to focus the incident light on the lens for near vision, the refractive component adapted to focus the incident light on the lens for mid-range vision, and the refractive component combined with the negative first order of the diffractive component adapted to focus the incident light on the lens for far vision.
Claim 3
Dependent Claim
17 words
The lens of claim 1 wherein the diffractive component has a profile which is binary in phase.
Claim 4
Dependent Claim
43 words
The lens of claim 2 wherein said profile has a depth D given by ##EQU5## where λ 0 is about 550 nm and Δn is the difference between the index of refraction of the lens and the index of refraction of aqueous humor.
Claim 5
Dependent Claim
47 words
The lens of claim 2 wherein said profile radial transition locations, r m , are given by ##EQU6## wherein λ 0 is a wavelength and where m is 0, 1, 2, 3, . . . , and P is the power of the diffractive element in diopters.
References Cited (Backward Citations)
US4210391A
Cited
US4637697A
Cited
US5121979A
Cited
US5056908A
Cited
US4881805A
Cited
US5076684A
Cited
US5116111A
Cited
US5129718A
Cited
US4995715A
Cited
US4995714A
Cited
US5016977A
Cited
US5121980A
Cited
US5089023A
Cited
US5096285A
Cited
US5178636A
Cited
US5071207A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-09-05 | 1998-03-07 | 1998-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-05 | 2002-03-07 | 2002-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-05 | 2006-03-07 | 2006-09-06 | $7700.00 | Window Closed / Lapsed |