US3687528A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ophthalmic lenses with a progressively varying focal power
Assignee: LUNETIERS
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Filing: 1970-09-08
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Granted: 1972-08-29
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Expires: 1990-09-08
Abstract
Abstract Ophthalmic lens having a progressively variable focal power and comprising a refracting surface consisting at least partly of a surface having an umbilical curve, so called progression umbilical curve, along which the radius of curvature evolves so as to provide the desired progressive variation of the focal power of said lens, wherein the section of said refracting surface taken along a plane orthogonal to the umbilical curve, for a specific plane, is substantially a circle, and for any other orthogonal plane a curve of which the radius of curvature increases or decreases in the direction away from said progression umbilical curve according as the radius of curvature of said progression umbilical curve at the point of the orthogonal plane involved is respectively smaller or greater than the radius of the substantially circular section.
Inventors
- 👤 Bernard F Maitenaz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:34
CPC Classifications
G; G02; G02C; G02C7/00; G02C7/02; G02C7/06; G02C7/061; G02C7/063; G02C7/065
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
396 words
Ophthalmic lens having a progressively variable focal power, and comprising a refracting surface with a generally vertical meridian curve having a radius of curvature the value of which progressively varies according to a predetermined law to provide a desired power addition along said meridian curve, said refracting surface having at each point of said meridian curve two main radii of curvature having identical values, wherein said refracting suRface further comprises a curve intersecting said meridian curve at right angles and lying in a plane also at right angles to said meridian curve, said intersecting curve being of substantially circular shape with a radius having a value equal to that of the radius of curvature of the meridian curve at the point of intersection of said meridian curve with said curve of substantially circular shape, and dividing said refracting surface into a first surface portion in which the value of the radius of curvature of the meridian curve decreases in the direction away from said point of intersection and a second surface portion in which the value of the radius of curvature of the meridian curve increases in the direction away from said intersection point, and wherein the sections of said first surface portion through planes at right angles to the meridian curve are aspheric curves intersecting said meridian curve at respective points of intersection, each of said section curves having a radius of curvature the value of which at the respective point of intersection with the meridian curve is equal to that of the radius of curvature of the meridian curve at said respective point of intersection and which increases from said value of the radius of curvature at the respective point of intersection in the direction away from said respective point of intersection, whereas the sections of said second surface portion through planes at right angles to the meridian curve are other aspheric curves intersecting said meridian curve at other respective points of intersection, each of said other section curves having a radius of curvature the value of which at the respective point of intersection with the meridian curve is equal to that of the radius of curvature of the meridian curve at said respective point of intersection and which decreases from said value of the radius of curvature at the respective point of intersection in the direction away from said respective point of intersection.
Claim 2
Dependent Claim
396 words
Ophthalmic lens having a progressively variable focal power, and comprising a refracting surface with a generally vertical meridian curve having a radius of curvature the value of which progressively varies according to a predetermined law to provide a desired power addition along said meridian curve, said refracting surface having at each point of said meridian curve two main radii of curvature having identical values, wherein said refracting suRface further comprises a curve intersecting said meridian curve at right angles and lying in a plane also at right angles to said meridian curve, said intersecting curve being of substantially circular shape with a radius having a value equal to that of the radius of curvature of the meridian curve at the point of intersection of said meridian curve with said curve of substantially circular shape, and dividing said refracting surface into a first surface portion in which the value of the radius of curvature of the meridian curve decreases in the direction away from said point of intersection and a second surface portion in which the value of the radius of curvature of the meridian curve increases in the direction away from said intersection point, and wherein the sections of said first surface portion through planes at right angles to the meridian curve are aspheric curves intersecting said meridian curve at respective points of intersection, each of said section curves having a radius of curvature the value of which at the respective point of intersection with the meridian curve is equal to that of the radius of curvature of the meridian curve at said respective point of intersection and which increases from said value of the radius of curvature at the respective point of intersection in the direction away from said respective point of intersection, whereas the sections of said second surface portion through planes at right angles to the meridian curve are other aspheric curves intersecting said meridian curve at other respective points of intersection, each of said other section curves having a radius of curvature the value of which at the respective point of intersection with the meridian curve is equal to that of the radius of curvature of the meridian curve at said respective point of intersection and which decreases from said value of the radius of curvature at the respective point of intersection in the direction away from said respective point of intersection.
Claim 3
Dependent Claim
105 words
Ophthalmic lens according to claim 1, wherein the value of the radius of curvature of the meridian curve progressively varies from a first value at a first point of said meridian curve located in said first surface portion to a second value at a second point of said meridian curve located in said second surface portion, and wherein the respective values of the radii of curvature of said sections of the first surface portion tend, while increasing, towards said second value, whereas the respective values of the radii of curvature of said sections of the second surface portion tend, while decreasing, towards said first value.
Claim 4
Dependent Claim
70 words
Ophthalmic lens according to claim 2, wherein at least one of the two section curves which are perpendicular to the meridian curve at said first and second points, respectively, is a curve along which the plane tangent to the refracting surface at any point of said curve makes a constant angle with the plane which is perpendicular to the meridian curve and which includes the optical center of the lens.
Claim 5
Dependent Claim
60 words
Ophthalmic lens according to claim 2, wherein at least one of the two section curves which are perpendicular to the meridian curve at said first and second points, respectively, is an umbilical curve, that is a curve each point of which is a point of the refracting surface where the two main radii of the refracting surfaces have identical values.
Claim 6
Dependent Claim
22 words
Ophthalmic lens according to claim 4, wherein said refracting surface is symmetrical in relation to at least one of said umbilical curves.
Claim 7
Dependent Claim
26 words
Ophthalmic lens according to claim 4, wherein said refracting surface is symmetrical about at least one of said first and second points of the meridian curve.
Claim 8
Dependent Claim
66 words
Ophthalmic lens according to claim 1, wherein said refracting surface further comprise, in the marginal portion of the lens, at least one line which is substantially parallel to the meridian curve and along which the plane tangent to the refracting surface at any point of said line makes a constant angle with the osculating plane of saId meridian curve at the optical center of the lens.
Claim 9
Dependent Claim
14 words
Ophthalmic lens according to claim 1, wherein said meridian curve lies in a plane.
Claim 10
Dependent Claim
66 words
Ophthalmic lens according to claim 8, wherein the plane of said meridian curve is inclined downwards from the temporal side to the nasal side of the lens when said lens is in its operative position in a spectacle mounting, and wherein any two points of the refracting surface which are equally spaced in the horizontal direction from said meridian curve have substantially the same optical characteristics.
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) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |