Method For Providing To A Wearer A Customized Progressive Spectacle Ophthalmic Lens

Patent metadata

Field	Value
Publication number	US-2016306191-A1
Application number	US-201415037964-A
Country	US
Kind code	A1
Filing date	Aug 27, 2014
Priority date	Nov 25, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

A method for providing to a wearer a customized progressive spectacle ophthalmic lens, comprising providing a residual astigmatism target value for the progressive spectacle ophthalmic lens-eye system according to a reference point, calculating a correction function, combining the correction function to the front or to the back surface of an initial optical data of an initial progressive spectacle ophthalmic lens.

First claim

1 . A method implemented by computer means for providing to a wearer a customized progressive spectacle ophthalmic lens, said customized progressive spectacle ophthalmic lens being characterized by a set of optical data, wherein the method comprises:
a) providing the prescription data of the wearer, said prescription data comprising the sphere, cylinder, axis and addition (Add) prescribed values for said wearer, the wearing conditions for the wearer and the coma of the eye of the wearer; b) providing an initial optical data characterizing an initial progressive spectacle ophthalmic lens suitable to fulfil the requirements of the prescription data of the wearer, comprising a front surface and a back surface, a far vision point (x_VL,y_VL), a near vision point (x_VP,y_VP) and a meridian line representing the locus of mean points of a wearer when he is looking from far to near vision points; c) choosing a reference point (x_ref;y_ref) on the meridian line of the initial progressive spectacle ophthalmic lens; d) calculating the residual astigmatism of the initial progressive spectacle ophthalmic lens-eye system when the eye of the wearer is looking through the reference point, AR_ini(x_ref;y_ref), and the residual coma of the initial progressive spectacle ophthalmic lens-eye system when the eye of the wearer is looking through to the reference point, CR_ini(x_ref;y_ref); e) calculating a residual astigmatism target value for the progressive spectacle ophthalmic lens-eye system according to the reference point, AR_cib(x_ref;y_ref), thanks to following equation:
| AR _ cib ( x _ ref;y _ ref )|= S×|CR _ ini ( x _ ref;y _ ref )|,
where 0.5≦S≦3 and where the values of AR_cib and CR_ini are in μm; f) calculating a correction function, SUR_cor(x;y), according to following steps:
(i) calculating AR_cor(x_ref;y_ref) according to following equation:
AR _ cor ( x _ ref;y _ ref )= AR _ cib ( x _ ref;y _ ref )− AR _ ini ( x _ ref;y _ ref )

(ii) determining the radius, R_cor, of the toroidal surface having the said AR_cor(x_ref;y_ref) value at the point (x_ref;y_ref);
a (iii) calculating SUR_cor(x;y) as being the points of said toroidal surface;
g) calculating the customized optical data of the customized progressive spectacle ophthalmic lens by combining the correction function SUR_cor(x;y) to the front or to the back surface of initial optical data of the initial progressive spectacle ophthalmic lens; and wherein (x,y) are geometrical coordinates on a surface.

2 . The method according to claim 1 , wherein the reference point on the meridian line of the initial progressive spectacle ophthalmic lens is chosen within the list consisting of the far vision point, the fitting point, the near vision point.

3 . The method according to claim 1 , wherein S is equal to 1.

4 . The method according to claim 1 , wherein the coma of the eye of the wearer is measured straightaway, in far vision conditions.

5 . The method according to claim 1 , the coma of the eye of the wearer is measured in near vision conditions.

6 . The method according to claim 1 , wherein the coma of the eye of the wearer is measured for an eye pupil comprised between 2 and 8 mm.

7 . The method according to claim 1 , wherein the initial optical data characterizing the initial progressive spectacle ophthalmic lens is obtained thanks to a standard progressive spectacle ophthalmic lens design and to the prescription data of the wearer.

8 . The method according to claim 1 , wherein the initial optical data characterizing the initial progressive spectacle ophthalmic lens is obtained thanks to optimisation of a progressive spectacle ophthalmic lens according to the prescription data of the wearer and to wearer specific parameters, such as for example eye-head coefficient, progression length, wearing conditions.

9 . The method according to claim 1 , wherein the wearing conditions are standard wearing conditions where the position of the lens with relation to the eye of the wearer is defined by a pantoscopic angle of −8 [deg.], a lens-pupil distance of 14 mm, a pupil-eye rotation center of 11.5 mm and a wrap angle of 0 [deg.].

10 . The method according to claim 1 wherein steps f) and g) consist of:
step f) further comprises a substep f2) consisting of:
f2) calculating a second correction function, SUR_cor2(x;y):
wherein SUR_cor2(x;y)=F(x;y);

wherein step g) comprises calculating the customized optical data of the customized progressive spectacle ophthalmic lens by combining the correction function SUR_cor(x;y) and the second correction function SUR_cor2(x;y) to the front or to the back surface of initial optical data of the initial progressive spectacle ophthalmic lens,
where F is chosen within the list consisting of:
a sphere function;
an atorization function;

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where 0.02≦C 1≦1 (C 1 in μm/D);

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Assignees

• Essilor Int

Inventors

• Marin Gildas
• Hernandez Castanedas Martha
• Calixte Laurent

Classifications

• G02C7/065

  Properties on the principal line · CPC title

• G02C13/005

  Measuring geometric parameters required to locate ophtalmic lenses in spectacles frames (apparatus for testing or instruments for examining the eyes per se A61B3/00; machines or devices and accessories for grinding the edges of lenses using spectacles as a template B24B9/144) · CPC title

• G02C2202/22

  Correction of higher order and chromatic aberrations, wave front measurement and calculation · CPC title

• G02C7/027 Primary

  considering wearer's parameters · CPC title

• G02C7/028

  Special mathematical design techniques · CPC title