Short corridor progressive addition lenses with reduced unwanted astigmatism

• US 7,229,173 B2
• Filed: 08/25/2004
• Issued: 06/12/2007
• Est. Priority Date: 08/25/2004
• Status: Expired due to Fees

• Current Assignee: Essilor International SA
• Original Assignee: Essilor International SA
• Inventors: Menezes, Edgar V.
• Primary Examiner(s): SCHWARTZ, JORDAN MARC
• Application Number:
  US10/925,721
• Publication Number:
  US 20060050236A1
• Time in Patent Office: 1,021 Days
• Field of Search: 351/169, 351/177
• US Class Current: 351/169
• CPC Class Codes: G02C 7/024 Methods of designing ophthalmic lenses
• CPC Class Codes: G02C 7/061 Spectacle lenses with progressively varying focal power
• CPC Class Codes: G02C 7/063 Shape of the progressive surface

Abstract

The invention provides lenses produced by the adding of two or more surfaces, in which lenses both the length of the corridor is shortened and the maximum unwanted astigmatism is reduced.

Claims

1. A method for designing a progressive addition lens, comprising the steps of:

a.) providing a first progressive addition surface having a first add power and a first corridor of a first length;

b.) expressing the first surface as a first plurality of sag values;

c.) multiplying the first plurality of sag values by a first blending function;

d.) providing a second progressive addition surface having a second add power and a second corridor of a second length;

e.) expressing the second surface as a second plurality of sag values;

f.) multiplying the second plurality of sag values by a second blending function that may be the same or different from the first blending function;

g.) adding the multiplied first and second plurality of sag values to produce a third progressive surface having the first add power, a third corridor wherein a length of the third corridor is at least about 1 mm less than the first and second corridor lengths.

2. The method of claim 1, wherein the first progressive addition surface design further comprises a first maximum unwanted astigmatism, the second progressive addition surface design further comprises a second maximum unwanted astigmatism and the third progressive addition surface design further comprises a third maximum unwanted astigmatism wherein the third maximum unwanted astigmatism is greater by about 0.2 or less diopters than one of the first and second maximum unwanted astigmatism.

9. The method of claim 1, wherein the second surface is of a different design than the first surface.

13. The method of claim 9, wherein the method farther comprises the step of scaling the first and the second surfaces.

17. The method of claim 1, further comprising the step of aspherizing a distance vision zone of the first or second surface.

21. A lens produced by the method of claim 1.

25. The lens of claim 21, wherein the lens is a spectacle lens.

29. The lens of claim 25, wherein a convex surface of the lens is of a symmetric, soft progressive design.

3. A method for designing a progressive addition lens, comprising the steps of:

a.) providing a first progressive addition surface having a first add power and a first corridor of a first length;

b.) expressing the first surface as a first plurality of sag values;

c.) multiplying the first plurality of sag values by a first blending function;

d.) providing a second progressive addition surface having a second add power and a second corridor of a second length;

e.) expressing the second surface as a second plurality of sag values;

f.) multiplying the second plurality of sag values by a second blending function that may be the same or different from the first blending function;

g.) blending radially the multiplied first and second plurality of sag values to produce a third progressive surface having the first add power, a third corridor wherein a length of the third corridor is at least about 1 mm less than the first and second corridor lengths.

4. The method of claim 3, wherein the first progressive addition surface design further comprises a first maximum unwanted astigmatism, the second progressive addition surface design further comprises a second maximum unwanted astigmatism and the third progressive addition surface design further comprises a third maximum unwanted astigmatism wherein the third maximum unwanted astigmatism is greater by about 0.2 or less diopters than one of the first and second maximum unwanted astigmatism.

10. The method of claim 3, wherein the second surface is of a different design than the first surface.

14. The method of claim 10, wherein the method further comprises the step of scaling the first and the second surfaces.

18. The method of claim 3, further comprising the step of aspherizing a distance vision zone of the first or second surface.

22. A lens produced by the method of claim 3.

26. The lens of claim 22, wherein the lens is a spectacle lens.

30. The lens of claim 26, wherein a convex surface of the lens is of a symmetric, soft progressive design.

5. A method for designing a progressive addition lens, comprising the steps of:

a.) providing a first progressive addition surface having a first add power and a first corridor of a first length;

b.) expressing the first surface as a first plurality of sag values;

c.) multiplying the first plurality of sag values by a first blending function;

d.) providing a second progressive addition surface having a second add power and a second corridor of a second length;

e.) expressing the second surface as a second plurality of sag values;

f.) multiplying the second plurality of sag values by a second blending function that may be the same or different from the first blending function;

g.) adding the multiplied first and second plurality of sag values to produce a third progressive surface having the first add power, a third corridor wherein a length of the third corridor is at least about 1 mm less than one of the first and second corridor lengths.

6. The method of claim 5, wherein the first progressive addition surface design further comprises a first maximum unwanted astigmatism, the second progressive addition surface design farther comprises a second maximum unwanted astigmatism and the third progressive addition surface design further comprises a third maximum unwanted astigmatism wherein the third maximum unwanted astigmatism is greater by about 0.2 or less diopters than one of the first and second maximum unwanted astigmatism.

11. The method of claim 5, wherein the second surface is of a different design than the first surface.

15. The method of claim 11, wherein the method further comprises the step of scaling the first and the second surfaces.

19. The method of claim 5, further comprising the step of aspherizing a distance vision zone of the first or second surface.

23. A lens produced by the method of claim 5.

27. The lens of claim 23, wherein the lens is a spectacle lens.

31. The lens of claim 27, wherein a convex surface of the lens is of a symmetric, soft progressive design.

7. A method for designing a progressive addition lens, comprising the steps of:

a.) providing a first progressive addition surface having a first add power and a first corridor of a first length;

b.) expressing the first surface as a first plurality of sag values;

c.) multiplying the first plurality of sag values by a first blending function;

d.) providing a second progressive addition surface having a second add power and a second corridor of a second length;

e.) expressing the second surface as a second plurality of sag values;

f.) multiplying the second plurality of sag values by a second blending function that may be the same or different from the first blending function;

g.) blending radially the multiplied first and second plurality of sag values to produce a third progressive surface having the first add power, a third corridor wherein a length of the third corridor is at least about 1 mm less than one of the first and second corridor lengths.

8. The method of claim 7, wherein the first progressive addition surface design further comprises a first maximum unwanted astigmatism, the second progressive addition surface design farther comprises a second maximum unwanted astigmatism and the third progressive addition surface design further comprises a third maximum unwanted astigmatism wherein the third maximum unwanted astigmatism is greater by about 0.2 or less diopters than one of the first and second maximum unwanted astigmatism.

12. The method of claim 7, wherein the second surface is of a different design than the first surface.

16. The method of claim 12, wherein the method further comprises the step of scaling the first and the second surfaces.

20. The method of claim 7, further comprising the step of aspherizing a distance vision zone of the first or second surface.

24. A lens produced by the method of claim 7.

28. The lens of claim 24, wherein the lens is a spectacle lens.

32. The lens of claim 28, wherein a convex surface of the lens is of a symmetric, soft progressive design.