Process and system for manufacturing an ophthalmic lens

Patent metadata

Field	Value
Publication number	US-10131102-B2
Application number	US-201414895830-A
Country	US
Kind code	B2
Filing date	Jun 6, 2014
Priority date	Jun 7, 2013
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

A process for manufacturing an ophthalmic lens having at least one optical function, includes the following steps: additively manufacturing ( 100 ) an intermediate optical element by depositing a plurality of preset volume elements of at least one material having a preset refractive index, the intermediate optical element including a target ophthalmic lens and a thickness allowance consisting of a portion of the plurality of volume elements; and subtractively manufacturing ( 300 ), by machining, the target ophthalmic lens from the intermediate optical element, the machining being carried out in a preset sequence, of at least one step, the preset sequence making it possible to subtract the thickness allowance, the additive manufacturing step ( 100 ) including a step of determining a manufacturing setpoint for the intermediate optical element in which the thickness allowance is determined depending on the preset sequence defined in the subtractive manufacturing step ( 300 ).

First claim

The invention claimed is:

1. A process for manufacturing an ophthalmic lens having at least one optical function, comprising the following steps:
additively manufacturing an intermediate optical element by depositing a plurality of predetermined volume elements of at least one material having a predetermined refractive index, said intermediate optical element comprising a target ophthalmic lens adjoined to an extra thickness consisting of a portion of said plurality of volume elements; and
subtractively manufacturing by machining said target ophthalmic lens from said intermediate optical element, the machining being carried out in a predetermined sequence, of at least one step, said predetermined sequence allowing said extra thickness to be subtracted,
said additive manufacturing step comprising a step of determining manufacturing settings for said intermediate optical element in which said extra thickness is determined depending on said predetermined sequence defined in the subtractive manufacturing step.

2. The process as claimed in claim 1 , wherein the extra thickness generated in the additive manufacturing step leading to the intermediate optical element and then subtracted in the subtractive manufacturing step leading to the target ophthalmic lens has a dimension between 1 μm and 1000 μm inclusive.

3. The process as claimed in claim 1 , wherein said predetermined sequence comprises at least one step chosen from one or more of a roughing step, a finishing step, and a polishing step.

4. The process as claimed in claim 3 , wherein said predetermined sequence is chosen from one of:
a roughing step carried out on the intermediate optical element leading to a roughed intermediate optical element, followed by a finishing step carried out on said roughed intermediate optical element leading to a first finished intermediate optical element, followed by a polishing step carried out on said first finished intermediate optical element leading to the target ophthalmic lens, a finishing step carried out on the intermediate optical element leading to a second finished intermediate optical element, followed by a polishing step carried out on said second finished intermediate optical element leading to the target ophthalmic lens, and
a polishing step carried out on the intermediate optical element leading to the target ophthalmic lens.

5. The process as claimed in claim 3 , wherein said predetermined sequence is identical or different on the entire intermediate optical element.

6. The process as claimed in claim 1 , wherein the additively manufacturing step is carried out by depositing a plurality of predetermined volume elements of a given constituent material of the target ophthalmic lens and extra thickness.

7. The process as claimed in claim 1 , wherein the additively manufacturing step is carried out by depositing a plurality of predetermined volume elements of at least two different materials, the materials especially differing in their refractive index or in their intrinsic abradability.

8. The process as claimed in claim 1 , wherein the additive manufacturing step implements one of a three-dimensional printing, stereolithography, a mask projection stereolithography process, a selective laser melting or sintering process, and a thermoplastic filament extrusion process.

9. The process as claimed in claim 1 , wherein said step of determining a manufacturing setting for said intermediate optical element includes the following steps:
determining target geometric characteristics for said ophthalmic lens from characteristics of said optical function to be given to said ophthalmic lens,
determining said extra thickness, from said determined target geometric characteristics and characteristics associated with said predetermined subtractive manufacturing sequence, and
deducing the geometric characteristics of said intermediate optical element from said determined target geometric characteristics and from said determined extra thickness.

10. The process as claimed in claim 9 , wherein the step of determining said extra thickness includes taking into account material physical data associated with said predetermined subtractive manufacturing sequence.

11. The process as claimed in claim 9 , wherein said optical function to be given to said ophthalmic lens is characteristic of prescription values associated with a wearer of said ophthalmic lens and complementary fitting data of a predetermined frame, personalization data, and/or frame-shape data.

12. The process as claimed in claim 1 , wherein the intermediate optical element has an outline substantially equal to an outline configured to be inserted into a predetermined frame.

13. A system for manufacturing an ophthalmic lens, the system comprising:
an additive manufacturing machine and at least one subtractive manufacturing machine, in order to manufacture an ophthalmic lens; and
at least one command/control unit provided with system elements configured to run a computer program comprising instructions configured to implement each of the steps of the process as claimed in claim 1 .

14. The manufacturing system as claimed in claim 13 , further comprising a varnishing machine configured to deposit a varnish on the element output by the subtractive manufacturing machine.

15. The manufacturing system as claimed in claim 13 , wherein the additive manufacturing machine comprises a manufacturing holder that is removable and configured to serve as a manufacturing holder for the subtractive manufacturing machine.

16. The process as claimed in claim 2 , wherein said predetermined sequence comprises at least one step chosen from one or more of a roughing step, a finishing step, and a polishing step.

17. The process as claimed in claim 16 , wherein said predetermined sequence is chosen from one of:
a roughing step carried out on the intermediate optical element leading to a roughed intermediate optical element, followed by a finishing step carried out on said roughed intermediate optical element leading to a first finished intermediate optical element, followed by a polishing step carried out on said first finished intermediate optical element leading to the target ophthalmic lens, a finishing step carried out on the intermediate optical element leading to a second finished intermediate optical element, followed by a polishing step carried out on said second finished intermediate optical element leading to the target ophthalmic lens, and
a polishing step carried out on the intermediate optical element leading to the target ophthalmic lens.

18. The process as claimed in claim 4 , wherein said predetermined sequence is identical or different on the entire intermediate optical element.

19. The process as claimed in claim 17 , wherein said predetermined sequence is identical or different on the entire intermediate optical element.

20. The process as claimed in claim 2 , wherein the extra thickness has a dimension between 30 μm and 1000 μm inclusive.

Assignees

• Essilor Int
• Essilor Int

Inventors

• Quere Loic
• Gourraud Alexandre
• Allione Pascal
• Begon Cedric
• Le Saux Gilles

Classifications

• B29D11/00009 Primary

  Production of simple or compound lenses · CPC title

• B29D11/00932

  Combined cutting and grinding thereof · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• G02C2202/16

  Laminated or compound lenses · CPC title

• B29D11/00432

  Auxiliary operations, e.g. machines for filling the moulds (B29D11/00125 takes precedence) · CPC title