US5650838A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Programmable smooth junctions on lenses
Assignee: Johnson and Johnson Vision Care Inc
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Filing: 1995-05-04
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Granted: 1997-07-22
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Expires: 2015-05-04
Abstract
Abstract Programmable smooth junctions are provided for lenses and molds therefor, particularly for toric lens designs, which enable a numerically controlled (NC) machine to be programmed to machine smooth junctions or transitions between adjacent regions of a lens which have different thicknesses or radii of curvature. First and second mathematical functions f(a) and f(b) are defined which specify the curves of first and second segments of a lens surface. The slope dy/dx is derived of the first and second mathematical functions f(a) and f(b) at the transition between the first and second segments of the lens surface. A mathematical function is defined which describes a desired transition between the first and second segments of the lens. The first and second mathematical functions f(a) and f(b), the derived slopes dy/dx of the first and second mathematical functions f(a) and f(b), and the mathematical function describing the desired transition are then utilized to program a numerically controlled machine to machine the first and second segments of the lens surface and the desired transition between the first and second segments.
Inventors
- 👤 Jeffrey H. Roffman
- 👤 Timothy A. Clutterbuck
- 👤 Yulin X. Lewis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 02:44
CPC Classifications
G; G02; G02C; G02C7/00; G02C7/02; G02C7/024; G02C7/028; G02C7/04; G02C7/047
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
259 words
A method of designing a lens which enables a numerically controlled machine to be programmed to machine smooth transitions between adjacent regions of the lens which have different thicknesses or radii of curvature, comprising: a. defining a first mathematical function f(a) which specifies the curve of a first segment of a lens surface; b. defining a second mathematical function f(b) which specifies the curve of a second segment of the lens surface; c. deriving the slope dy/dx of the first mathematical function f(a) at the endpoint of the first segment of the lens surface nearest the second segment; d. deriving the slope dy/dx of the second mathematical function f(b) at the endpoint of the second segment of the lens surface nearest the first segment; e. defining a mathematical function which describes a desired transition between the first and second segments of the lens; f. scaling the x interval between the endpoints of the first and second segments of the lens surface and scaling the y interval between the endpoints of the first and second segments of the lens surface to ±1 where the midpoint between the endpoints of the first and second segments is defined to be zero; and g. utilizing the first and second mathematical functions f(a) and f(b), the derived slopes dy/dx of the first and second mathematical functions f(a) and f(b), and the mathematical function describing the desired transition to program a numerically controlled machine to machine the first and second segments of the lens surface and the desired transition between the first and second segments.
Claim 2
Independent Claim
259 words
A method of designing a lens which enables a numerically controlled machine to be programmed to machine smooth transitions between adjacent regions of the lens which have different thicknesses or radii of curvature, comprising: a. defining a first mathematical function f(a) which specifies the curve of a first segment of a lens surface; b. defining a second mathematical function f(b) which specifies the curve of a second segment of the lens surface; c. deriving the slope dy/dx of the first mathematical function f(a) at the endpoint of the first segment of the lens surface nearest the second segment; d. deriving the slope dy/dx of the second mathematical function f(b) at the endpoint of the second segment of the lens surface nearest the first segment; e. defining a mathematical function which describes a desired transition between the first and second segments of the lens; f. scaling the x interval between the endpoints of the first and second segments of the lens surface and scaling the y interval between the endpoints of the first and second segments of the lens surface to ±1 where the midpoint between the endpoints of the first and second segments is defined to be zero; and g. utilizing the first and second mathematical functions f(a) and f(b), the derived slopes dy/dx of the first and second mathematical functions f(a) and f(b), and the mathematical function describing the desired transition to program a numerically controlled machine to machine the first and second segments of the lens surface and the desired transition between the first and second segments.
Claim 3
Dependent Claim
22 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes a linear function.
Claim 4
Dependent Claim
23 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes a single bridge radius.
Claim 5
Dependent Claim
21 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes multiple radii.
Claim 6
Dependent Claim
22 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes an aspheric radius.
Claim 7
Dependent Claim
22 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes multiple aspheric radii.
Claim 8
Dependent Claim
29 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes any combination of single or multiple spheric and aspheric radii.
Claim 9
Dependent Claim
25 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes multiple radii with a reversed curve.
Claim 10
Dependent Claim
38 words
A method of designing a lens as claimed in claim 1, wherein a thicker central optical zone of the contact lens is connected to a thinner peripheral lenticular zone of the contact lens with a defined transition curve.
Claim 11
Dependent Claim
22 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes a power function.
Claim 12
Dependent Claim
23 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes an asymptotic connection function.
Claim 13
Dependent Claim
22 words
A method of designing a lens as claimed in claim 1, wherein the mathematical function describing the transition describes a trigonometric function.
Claim 14
Dependent Claim
11 words
A contact lens produced according to the method of claim 1.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2000-07-21 | 2001-01-20 | 2001-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-07-21 | 2005-01-20 | 2005-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-07-21 | 2009-01-20 | 2009-07-22 | $7700.00 | Window Closed / Lapsed |