Semi-finished lens to be machined for forming an ophthalmic lens to be mounted in a spectacle frame, set and a method involving the same

Patent metadata

Field	Value
Publication number	US-11072135-B2
Application number	US-201816002082-A
Country	US
Kind code	B2
Filing date	Jun 7, 2018
Priority date	Jun 8, 2017
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

Disclosed is a semi-finished lens that includes a blank formed in a first material having a first hardness, the blank having an outline, a first face and a second face configured to be surfaced so as to constitute a first optical face of the ophthalmic lens, and a top layer formed in a second material having a second hardness greater than the first hardness, the top layer having an outline, a first face and a second face, the second face of the top layer being arranged on the first face of the blank. The outline of the top layer is equal to or included in the outline of the blank, and satisfies to a predetermined dimensional selection criterion involving the final outline of the ophthalmic lens.

First claim

The invention claimed is:

1. A set comprising:
(i) a semi-finished lens to be machined for forming an ophthalmic lens dimensioned for the ophthalmic lens to be mounted in a spectacle frame, the semi finished lens comprising
a blank formed in a first material having a first hardness, the blank having
an outline,
a first face, and
a second face configured to be surfaced to constitute a first optical face of the ophthalmic lens, and

a top layer formed in a second material having a second hardness that is greater than the first hardness, the top layer having
an outline,
a first face, and
a second face of the top layer arranged on the first face of the blank,
the outline of the top layer being equal to or included in the outline of the blank;

(ii) a first data support containing data representative of a final outline of said ophthalmic lens, the outline of the top layer satisfying a predetermined dimensional selection criterion involving said final outline of the ophthalmic lens as represented by the data representative of said final outline contained in the first data support; and
(iii) a second data support containing additional data representative of a range of predetermined outlines, the outline of the top layer of the semi-finished lens being the outline in said range for which the difference between the area of the surface delimited by the outline of the top layer and the area of the surface delimited by the final outline of the ophthalmic lens is minimized, said predetermined dimensional selection criterion of the outline of the top layer being the minimization of said difference.

2. The set according to claim 1 , wherein, independently of said predetermined dimensional criterion, the outline of the top layer equates or includes the final outline of the ophthalmic lens and the outline of the blank equates or includes the final outline of the ophthalmic lens.

3. The set according to claim 2 , wherein the outline of the blank satisfies a predetermined dimensional selection criterion involving the final outline of the ophthalmic lens.

4. The set according to claim 2 , wherein said blank is configured to provide a fitting rib to the ophthalmic lens, the fitting rib being configured to be received in a fitting groove of a rim of said spectacle frame.

5. The set according to claim 2 , wherein the first material comprises plastic.

6. The set according to claim 1 , wherein the outline of the blank satisfies a predetermined dimensional selection criterion involving the final outline of the ophthalmic lens.

7. The set according to claim 6 , wherein said blank is configured to provide a fitting rib to the ophthalmic lens, the fitting rib being configured to be received in a fitting groove of a rim of said spectacle frame.

8. The set according to claim 1 , wherein said blank is configured to provide a fitting rib to the ophthalmic lens, the fitting rib being configured to be received in a fitting groove of a rim of said spectacle frame.

9. The set according to claim 1 , wherein the first material comprises plastic.

10. The set according to claim 1 , wherein the second material comprises glass.

11. The set according to claim 1 , wherein the top layer comprises an electrochromic element.

12. The set according to claim 1 , wherein the top layer comprises a light-guide optical element.

13. The set according to claim 1 , wherein the first face of the top layer is configured to constitute a second optical face of the ophthalmic lens.

14. The set according to claim 1 , wherein the semi-finished lens is configured to be alternatively machined to form another ophthalmic lens dimensioned for said other ophthalmic lens to be mounted in another spectacle frame, the outline of the top layer further satisfying another predetermined dimensional selection criterion involving the final outline of the other ophthalmic lens.

15. The set according to claim 1 , wherein said range of different predetermined outlines comprises plural predetermined outlines that are homothetic with respect to each other and that define surfaces of distinct respective areas.

16. A method for manufacturing an ophthalmic lens having a first optical face, a second optical face, and a final outline for the ophthalmic lens to be mounted in a spectacle frame, the method comprising:
providing:
a semi-finished lens including
a blank formed in a first material having a first hardness, the blank having
an outline,
a first face, and
a second face configured to be surfaced to constitute a first optical face of the ophthalmic lens, and

a top layer formed in a second material having a second hardness that is greater than the first hardness, the top layer having
an outline,
a first face, and
a second face of the top layer arranged on the first face of the blank,
the outline of the top layer being equal to or included in the outline of the blank,
the outline of the top layer satisfying a predetermined dimensional selection criterion involving the final outline of the ophthalmic lens,

a first data support containing data representative of said final outline of said ophthalmic lens to be mounted in said spectacle frame, and
a second data support containing additional data representative of a range of predetermined outlines;

retrieving the data representative of said final outline from the first data support; and
using the retrieved data representative of said final outline, surfacing the second face of the blank of the semi-finished lens to form the first optical face of the ophthalmic lens,
wherein the additional data is used so that the outline of the top layer of the semi-finished lens is the outline in said range for which the difference between the area of the surface delimited by the outline of the top layer and the area of the surface delimited by the final outline of the ophthalmic lens is minimized, said predetermined dimensional selection criterion of the outline of the top layer being the minimization of said difference.

17. The method according to claim 16 , further comprising edging the blank of the semi-finished lens of the set for the ophthalmic lens to be mounted in the spectacle frame.

18. The method according to claim 16 , further comprising edging the top layer of the semi-finished lens of the set for the ophthalmic lens to be mounted in the spectacle frame.

19. The method according to claim 16 , wherein said range of different predetermined outlines comprises plural predetermined outlines that are homothetic with respect to each other and that define surfaces of distinct respective areas.

Assignees

• Essilor Int

Inventors

• Padiou Jean-Marc
• Marchal Jeanne
• Saulny Jonathan

Classifications

• B24B9/20 Primary

  of plastics · CPC title

• G02C2202/08

  Series of lenses, lens blanks · CPC title

• G02C2202/16

  Laminated or compound lenses · CPC title

• G02C7/02

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

• G02C7/101

  having an electro-optical light valve (electro-optical elements per se G02F) · CPC title