Method of making a spectacle lens providing an astigmatic correction and spectacles including said spectacle lens

Patent metadata

Field	Value
Publication number	US-9459468-B2
Application number	US-201313901270-A
Country	US
Kind code	B2
Filing date	May 23, 2013
Priority date	May 23, 2012
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

A method of making a spectacle lens providing at least an astigmatic correction includes measuring a direction of an axis of an astigmatism of an eye for each of three different directions of gaze of the eye. Thereafter, a position of the spectacle lens is determined relative to the eye. A shape of a surface of the spectacle lens is computed based on the determined position of the spectacle lens relative to the eye and the at least three measured directions of the axis of the astigmatism. A primary orientation of the eye is determined based on the three measured directions of the axis of the astigmatism. The shape of the surface of the spectacle lens is calculated based on the determined position of the spectacle lens relative to the eye and by applying Listing's Law based on the determined primary orientation of the eye.

First claim

What is claimed is:

1. A method of making a spectacle lens providing at least an astigmatic correction, wherein the method comprises the steps of:
measuring a direction of an axis of an astigmatism of an eye for each of at least three different directions of gaze of the eye;
individually determining a position of the spectacle lens relative to the eye; and,
computing a shape of a surface of the spectacle lens based on the individually determined position of the spectacle lens relative to the eye and the at least three measured directions of the axis of the astigmatism.

2. The method according to claim 1 , wherein the measuring of the direction of the axis of the astigmatism of the eye is performed for more than 15 different directions of gaze,
wherein the calculating of the shape of the surface of the spectacle lens includes a simulation of light rays traversing the eye and the spectacle lens for a plurality of different directions of gaze of the eye; and,
wherein the direction of the astigmatism of the eye for the plurality of different directions of gaze is determined by interpolation of the measured directions of the axis.

3. The method according to claim 1 , further comprising determining a primary orientation of the eye based on the at least three measured directions of the axis of the astigmatism, wherein the shape of the surface of the spectacle lens is calculated based on the individually determined position of the spectacle lens relative to the eye and by applying Listing's Law based on the determined primary orientation of the eye.

4. The method according to claim 3 , wherein the calculating of the shape of the surface of the spectacle lens includes a simulation of light rays traversing the eye and the spectacle lens for a plurality of different directions of gaze of the eye, and wherein, in the simulation, directions of the axis of the astigmatism of the eye are calculated for the plurality of directions of gaze by applying Listing's Law based on the individually determined primary orientation.

5. The method according to claim 3 , wherein at least two of the at least three different directions of gaze differ by more than 25° in a vertical direction relative to the eye.

6. The method according to claim 3 , wherein at least two of the at least three different directions of gaze differ by more than 25° in a horizontal direction relative to the eye.

7. The method according to claim 3 , wherein at least two of the at least three directions of gaze are situated in an azimuthal direction about a straight direction of gaze outside of an angular range of ±10° from a vertical direction and outside of an angular range of ±10° from a horizontal direction.

8. The method according to claim 3 , wherein the direction of gaze in the primary orientation is orthogonal to a plane including the axes of rotation for rotational movement of the eye according to Listing's Law.

9. The method according to claim 1 , wherein the computing of the shape of the surface of the spectacle lens includes an optimization of a distribution of remaining aberrations for different directions of gaze.

10. The method according to claim 1 , wherein deviations of orientations of the eye from Listing's Law occurring due to a convergence of the eye when viewing on a close object are considered.

11. The method according to claim 1 , wherein a refraction of the eye is simulated for the plurality of different directions of gaze such that a cylindrical power of the astigmatic correction is constant for the different directions of gaze.

12. The method according to claim 1 , wherein a refraction of the eye is simulated for the plurality of different directions of gaze such that a spherical power of a spherical correction is constant for the different directions of gaze.

13. The method according to claim 1 , wherein a distance of an object from the eye is simulated for the plurality of different directions of gaze such that the distance for downward directions of gaze is smaller than the distance for horizontal directions of gaze or upward directions of gaze.

14. The method according to claim 1 , wherein the shape of the surface of the spectacle lens is calculated such that the spectacle lens provides spherical powers which are smaller for upward directions of gaze than for downward directions of gaze.

15. The method according to claim 1 , wherein the determining of the position of the spectacle lens relative to the eye is determined based on a geometry of a selected spectacle frame.

16. The method according to claim 1 , further comprising shaping the surface of the spectacle lens according to the calculated shape of the surface.

17. Spectacles for a first and a second eye of a wearer, at least the first eye having an astigmatism, the astigmatism defining an axis with a direction measured in at least three different directions of gaze of the first eye, the spectacles comprising:
a spectacle frame;
a first spectacle lens mounted on said spectacle frame so as to correspond to the first eye of the wearer;
a second spectacle lens mounted on said spectacle frame so as to correspond to the second eye of the wearer;
said first spectacle lens having an individually determined position relative to the first eye; and,
said first spectacle lens defining a surface having a computed shape based on the individually determined position of the first spectacle lens relative to the first eye and the at least three measured directions of the axis of the astigmatism.

18. A computer readable medium storing information representing a computer program configured to instruct an optical system to perform a method comprising:
measuring a direction of an axis of an astigmatism of an eye for each of at least three different directions of gaze of the eye;
individually determining a position of the spectacle lens relative to the eye; and,
computing a shape of a surface of the spectacle lens based on the individually determined position of the spectacle lens relative to the eye and the at least three measured directions of the axis of the astigmatism.

19. The method according to claim 3 , wherein at least two of the at least three different directions of gaze differ by more than 35° in a vertical direction relative to the eye.

20. The method according to claim 3 , wherein at least two of the at least three different directions of gaze differ by more than 35° in a horizontal direction relative to the eye.

21. A method of making a spectacle lens providing at least an astigmatic correction, wherein the method comprises the steps of:
measuring a direction of an axis of an astigmatism of an eye for each of at least three different directions of gaze of the eye;
individually determining a position of the spectacle lens relative to the eye; and,
computing a shape of a surface of the spectacle lens based on the individually determined position of the spectacle lens relative to the eye and the at least three measured directions of the axis of the astigmatism,
wherein the measuring of the direction of the axis of the astigmatism of the eye is performed for more than 30 different directions of gaze;
wherein the calculating of the shape of the surface of the spectacle lens includes a simulation of light rays traversing the eye and the spectacle lens for a plurality of different directions of gaze of the eye; and,
wherein the direction of the astigmatism of the eye for the plurality of different directions of gaze is determined by interpolation of the measured directions

Assignees

• Zeiss Carl Vision Int Gmbh

Inventors

• Wietschorke Helmut

Classifications

• G02C7/028

  Special mathematical design techniques · CPC title

• G02C7/02

  Lenses; Lens systems {; Methods of designing lenses} · CPC title

• G02C7/025

  considering parameters of the viewed object · CPC title

• A61B3/1035

  for measuring astigmatism (testing astigmatism A61B3/036) · CPC title

• G02C7/061

  Spectacle lenses with progressively varying focal power · CPC title