US5617155A
Expired / Lapsed
US
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Method for determining measurement parameters for a spectacle wearer
Assignee: EssilorLuxottica SA
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Filing: 1995-04-27
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Granted: 1997-04-01
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Expires: 2015-04-27
Abstract
Abstract A method for determining measurement parameters from the image of a spectacle wearer wearing a spectacle frame is disclosed in which the position of the center of the pupil of each eye is obtained automatically by analyzing the luminance gradient in the region of the pupils and the positions of the horizontal and vertical straight lines tangential to the frame are also obtained automatically by luminance gradient analysis and extraction of the contours of the frame, enabling said parameters to be calculated accurately.
Inventors
- 👤 Christian Ducarouge
- 👤 Richard Grisel
- 👤 Nicholas Giraud
- 👤 Helene Sottocasa
- 👤 Alain Chansavoir
- 👤 Ahmed Haddadi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 11:30
CPC Classifications
A; A61; A61B; A61B3/00; A61B3/10; A61B3/11; G; G02; G02C; G02C13/00; G02C13/003; G02C13/005
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
86 words
A method for determining measurement parameters for a spectacle wearer comprising the steps of: generating an image of a spectacle wearer provided with a spectacle frame; determining automatically, on said image, by luminance gradient analysis, where a plurality of horizontal and vertical straight lines tangential to said frame would be positioned; determining automatically, on said image, by luminance gradient analysis, where the center of each pupil of the eyes of said wearer would be positioned; and calculating the values of said measurement parameters from said positions.
Claim 2
Independent Claim
86 words
A method for determining measurement parameters for a spectacle wearer comprising the steps of: generating an image of a spectacle wearer provided with a spectacle frame; determining automatically, on said image, by luminance gradient analysis, where a plurality of horizontal and vertical straight lines tangential to said frame would be positioned; determining automatically, on said image, by luminance gradient analysis, where the center of each pupil of the eyes of said wearer would be positioned; and calculating the values of said measurement parameters from said positions.
Claim 3
Dependent Claim
42 words
The method according to claim 1, wherein the positions of the tangential horizontal and vertical straight lines are determined at an inside contour of each half-frame on said image and which further comprises extracting a contour of said frame from said image.
Claim 4
Dependent Claim
112 words
A method according to claim 1, which comprises the steps of: supplying at least a real contour of said frame, and the angles of inclination of said frame; calculating, as a function of said angles of inclination, a projection of said real contour on said image; comparing said projection with the contours extracted from said image by sweeping said projection over said image and calculating therefrom, for each position of said projection, the correlation between said projection and said contours extracted from said image; determining the positions of the horizontal and vertical straight lines tangential to said frame, using the position of said projection for which said correlation is at a maximum.
Claim 5
Dependent Claim
52 words
A method according to claim 3, wherein the step of calculating the values of said measurement parameters from said positions is achieved by comparing the relative positions of the centers of the pupils of the eyes of said spectacle wearer and the straight lines tangential to the inside contours of said frame.
Claim 6
Dependent Claim
31 words
A method according to claim 1 which further comprises defining contours of the frame using the position measurements associated with the horizontal and vertical lines which are tangential to the frame.
Claim 7
Independent Claim
112 words
A method for determining measurement parameters for a spectacle wearer comprising the steps of: generating an image of a spectacle wearer provided with a spectacle frame; determining automatically, on said image, by luminance gradient analysis, where a plurality of horizontal and vertical straight lines tangential to said frame would be positioned; determining automatically, on said image, by luminance gradient analysis, where the center of each pupil of the eyes of said wearer would be positioned; defining four windows of predetermined size around the center of each pupil, each window containing one straight line tangential to an inside contour of each half-frame; and calculating the values of said measurement parameters from said positions.
Claim 8
Independent Claim
112 words
A method for determining measurement parameters for a spectacle wearer comprising the steps of: generating an image of a spectacle wearer provided with a spectacle frame; determining automatically, on said image, by luminance gradient analysis, where a plurality of horizontal and vertical straight lines tangential to said frame would be positioned; determining automatically, on said image, by luminance gradient analysis, where the center of each pupil of the eyes of said wearer would be positioned; defining four windows of predetermined size around the center of each pupil, each window containing one straight line tangential to an inside contour of each half-frame; and calculating the values of said measurement parameters from said positions.
Claim 9
Dependent Claim
99 words
A method according to claim 6, wherein the step of determining the positions of the horizontal and vertical straight lines tangential to said frame comprises the steps, within each of said windows, of: determining, within said window, those points on the image for which the norm of the luminance gradient is higher than a threshold value in order to obtain the inside and outside contours of said frame within said window; determining the shape of said frame within said window, from said contours; determining, as a function of said window, a tangent to the inside contour of said frame.
Claim 10
Dependent Claim
36 words
A method according to claim 7, wherein said threshold value is selected whereby a predetermined number of said points on the image have a value of the norm of their luminance gradient above said threshold value.
Claim 11
Dependent Claim
96 words
A method according to claim 8, which includes a step of calculating angles of inclination comprising the steps of: supplying at least a real contour of said frame; calculating, for the various possible values of angles of inclination, a projection of said real contour on said image; comparing said projection with the contours extracted from said image by calculating, for said values of angles of inclination, the correlation between said projection and said contours extracted from said image; the values of said angles of inclination being those values for which said correlation is at a maximum.
Claim 12
Dependent Claim
113 words
A method according to claim 9, which further comprises the steps of: supplying at least a real contour of said frame, and the angles of inclination of said frame; calculating, as a function of said angles of inclination, the projection of said real contour on said image; comparing said projection with the contours extracted from said image by sweeping said projection over said image and calculating therefrom, for each position of said projection, the correlation between said projection and said contours extracted from said image; determining the positions of the horizontal and vertical straight lines tangential to said frame, using the position of said projection for which said correlation is at a maximum.
Claim 13
Dependent Claim
52 words
A method according to claim 10, wherein the step of calculating the values of said measurement parameters from said positions is achieved by comparing the relative positions of the centers of the pupils of the eyes of said spectacle wearer and the straight lines tangential to the inside contours of said frame.
Claim 14
Dependent Claim
31 words
A method according to claim 6 which further comprises defining contours of the frame using the position measurements associated with the horizontal and vertical lines which are tangential to the frame.
Claim 15
Independent Claim
125 words
A method for determining measurement parameters for a spectacle wearer comprising the steps of: generating an image of a spectacle wearer provided with a spectacle frame; determining automatically, on said image, by luminance gradient analysis, where a plurality of horizontal and vertical straight lines tangential to said frame would be positioned; determining automatically, on said image, by luminance gradient analysis, where the center of each pupil of the eyes of said wearer would be positioned by: determining a window covering the region of the pupil; determining, within said window, those points on the image having a luminance that is higher than a threshold value; and calculating the position of the centroid of said points; and calculating the values of said measurement parameters from said positions.
Claim 16
Independent Claim
125 words
A method for determining measurement parameters for a spectacle wearer comprising the steps of: generating an image of a spectacle wearer provided with a spectacle frame; determining automatically, on said image, by luminance gradient analysis, where a plurality of horizontal and vertical straight lines tangential to said frame would be positioned; determining automatically, on said image, by luminance gradient analysis, where the center of each pupil of the eyes of said wearer would be positioned by: determining a window covering the region of the pupil; determining, within said window, those points on the image having a luminance that is higher than a threshold value; and calculating the position of the centroid of said points; and calculating the values of said measurement parameters from said positions.
Claim 17
Dependent Claim
50 words
A method according to claim 13, wherein the step of determining said window is done by seeking, in the region of each pupil, that point in the image for which a norm of the gradient is a maximum, and then centering a window of a predetermined size on said point.
Claim 18
Dependent Claim
39 words
A method according to claim 14, which includes a step of defining four windows of predetermined size around the position of the center of each pupil, each containing one straight line tangential to the inside contour of each half-frame.
Claim 19
Dependent Claim
100 words
A method according to claim 15, wherein the step of determining the positions of the horizontal and vertical straight lines tangential to said frame automatically comprises the steps, within each of said windows, of: determining, within said window, those points on the image for which the norm of the luminance gradient is higher than the threshold value in order to obtain the inside and outside contours of said frame within said window; determining the shape of said frame within said window, from said contours; determining, as a function of said window, the tangent to the inside contour of said frame.
Claim 20
Dependent Claim
36 words
A method according to claim 16, wherein said threshold value is selected whereby a predetermined number of said points on the image have a value of the norm of their luminance gradient above said threshold value.
Claim 21
Dependent Claim
96 words
A method according to claim 17, which includes a step of calculating angles of inclination comprising the steps of: supplying at least a real contour of said frame; calculating, for the various possible values of angles of inclination, a projection of said real contour on said image; comparing said projection with the contours extracted from said image by calculating, for said values of angles of inclination, the correlation between said projection and said contours extracted from said image; the values of said angles of inclination being those values for which said correlation is at a maximum.
Claim 22
Dependent Claim
112 words
A method according to claim 18, which comprises the steps of: supplying at least a real contour of said frame, and the angles of inclination of said frame; calculating, as a function of said angles of inclination, the projection of said real contour on said image; comparing said projection with the contours extracted from said image by sweeping said projection over said image and calculating therefrom, for each position of said projection, the correlation between said projection and said contours extracted from said image; determining the positions of the horizontal and vertical straight lines tangential to said frame, using the position of said projection for which said correlation is at a maximum.
Claim 23
Dependent Claim
52 words
A method according to claim 19, wherein the step of calculating the values of said measurement parameters from said positions is achieved by comparing the relative positions of the centers of the pupils of the eyes of said spectacle wearer and the straight lines tangential to the inside contours of said frame.
References Cited (Backward Citations)
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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) | 2000-03-31 | 2000-09-30 | 2001-04-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-03-31 | 2004-09-30 | 2005-04-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-03-31 | 2008-09-30 | 2009-04-01 | $7700.00 | Window Closed / Lapsed |