Machining method by turning at least one surface of an ophthalmic lens, using a turning machine having at least one geometrical defect

Patent metadata

Field	Value
Publication number	US-10496076-B2
Application number	US-201515511530-A
Country	US
Kind code	B2
Filing date	Sep 25, 2015
Priority date	Oct 3, 2014
Publication date	Dec 3, 2019
Grant date	Dec 3, 2019

Abstract

Disclosed is a machining method by turning at least one surface of an ophthalmic lens, using a turning machine having at least one geometrical defect. The method includes a step ( 101 - 104 ) of determining a turning configuration for machining by turning the at least one surface of the ophthalmic lens, the turning configuration including turning parameters and machine defects parameters associated to the turning parameters.

First claim

The invention claimed is:

1. A machining method by turning at least one surface of an ophthalmic lens, using a turning machine ( 1 ) having at least one geometrical defect, wherein the method comprises:
a step ( 101 - 104 ) of determining a turning configuration for machining by turning the at least one surface of the ophthalmic lens, the turning configuration comprising turning parameters and machine defects parameters associated to the turning parameters,
wherein the turning configuration characterizes the at least one geometrical defect of the turning machine both as a function of the machine defects parameters and as a function of the turning parameters,
wherein the turning parameters, which the machine defects parameters are associated with in the turning configuration, include cutting data determined as a function of a material of the ophthalmic lens and as a function of a dynamic in cutting the ophthalmic lens; and
compensating for the at least one geometrical defects of the turning machine, by adjusting, before machining the ophthalmic lens, a defect correcting value in the turning machine, which defect correcting value is determined according to the machine defects parameters associated to the turning parameters.

2. The method according to claim 1 , wherein the turning configuration is determined for a set of lenses to machine, the lenses having at least one similar characteristic amongst material and average curvature; or for a single lens to machine, the lens having at least one predetermined characteristics amongst material and average curvature.

3. The method according to claim 2 , wherein the turning machine comprises a machining tool ( 24 ) configured for acting in three directions ( 16 , 17 , 18 ) in the turning machine ( 1 ) for machining the surface of the lens, and the at least one geometrical defect of the turning machine is a calibration defect according to a first direction ( 16 ) and/or to a second direction ( 18 ) amongst the three directions, and/or a perpendicular defect according to the first and third directions ( 16 , 17 ), and/or a parallelism defect according to the first direction ( 16 ) and/or second direction ( 18 ).

4. The method according to claim 1 , wherein the turning machine comprises a machining tool ( 24 ) configured for acting in three directions ( 16 , 17 , 18 ) in the turning machine ( 1 ) for machining the surface of the lens, and the at least one geometrical defect of the turning machine is a calibration defect according to a first direction ( 16 ) and/or to a second direction ( 18 ) amongst the three directions, and/or a perpendicular defect according to the first and third directions ( 16 , 17 ), and/or a parallelism defect according to the first direction ( 16 ) and/or second direction ( 18 ).

5. The method according to claim 1 , wherein the turning parameters which the machine defects parameters are associated with further comprise at least one of a material forming the lens, a direction of rotation of the ophthalmic lens, and an average curvature of the surface of the lens.

6. The method according to claim 5 , wherein the cutting data comprise at least one of a finishing feedrate, a cutting depth, a rotational speed, a tool aperture and a tool inclination.

7. The method according to claim 1 , wherein the step of determining the turning configuration comprises the steps of:
determining ( 103 ) at least one turning parameter from at least one parameter pertaining to the lens to machine;
selecting ( 104 ) the turning configuration from the at least one turning parameter determined; and
deducing ( 105 ) from the turning configuration selected the machine defects parameters.

8. The method of claim 7 , wherein the determining step further comprises determining the at least one turning parameter from at least one parameter pertaining to the turning machine used.

9. The method according to claim 1 , further comprising the steps of:
machining ( 202 ) by turning at least two checking surfaces according respectively to at least two distinct sets of predetermined turning parameters, the at least two checking surfaces having each a predetermined theoretical geometry;
determining ( 203 ) data representative of geometrical characteristics of the at least two checking surfaces machined;
processing ( 204 ) the data determined for determining machine defects parameters for each of the at least two sets of predetermined turning parameters; and
deducing and storing ( 205 ) at least two turning configurations comprising respectively turning parameters and machine defects parameters associated to the turning parameters.

10. The method according to claim 1 , comprising the steps of:
determining ( 301 ) a first turning configuration for machining by turning a first surface located on a first face of the ophthalmic lens, using the turning machine, the first turning configuration comprising first turning parameters and first machine defects parameters associated to the first turning parameters; and
determining ( 303 ) a second turning configuration for machining by turning a second surface located on a second face, opposite to the first face, of the ophthalmic lens, using the same turning machine, the second turning configuration comprising second turning parameters and second machine defects parameters associated to the second turning parameters;
the first turning parameters being distinct to the second turning parameters and the first machine defects parameters being distinct to the second machine defects parameters so that the first turning configuration is distinct to the second turning configuration.

11. The method according to claim 1 , wherein the at least one geometrical defect of the turning machine ( 1 ) has a value which is smaller than a first threshold value (S), and the defect correcting value is applied to the value of the at least one geometrical defect.

12. The method according to claim 1 , further comprising, before machining the ophthalmic lens, the step ( 107 ) of adjusting location of the machining tool ( 24 ) according to the machine defects parameters.

13. The method of claim 1 , wherein the method provides the ophthalmic lens with the turned at least one surface of the ophthalmic lens being at least one face ( 11 , 12 ) of the ophthalmic lens.

14. A non-transitory computer-readable medium having stored thereon computer instructions that when executed on a computer cause the computer to carry out each of the steps of the method of turning at least one surface of an ophthalmic lens, using a turning machine ( 1 ) having at least one geometrical defect, wherein the method comprises a step ( 101 - 104 ) of determining a turning configuration for machining by turning the at least one surface of the ophthalmic lens, the turning configuration comprising turning parameters and machine defects parameters associated to the turning parameters, wherein the turning configuration characterizes the at least one geometrical defect of the turning machine both as a function of the machine defects parameters and as a function of the turning parameters, wherein the turning parameters, which the machine defects parameters are associated with in the turning configuration, include cutting data determined as a function of a material of the ophthalmic lens and as a function of a dynamic in cutting the ophthalmic lens; and compensating for the at least one geometrical defects of the turning machine, by adjusting, before machining the ophthalmic lens, a defect correcting value in the turning machine, which defect correcting value is determined according to the machine defects parameters associated to the tur

Assignees

• Essilor Int

Inventors

• Meynen Mathieu
• Gourraud Alexandre
• Castro Martinez Luis Ricardo
• Quere Loic
• Pons Bernard

Classifications

• G05B2219/45136

  Turning, lathe · CPC title

• G05B19/4099 Primary

  Surface or curve machining, making three-dimensional [3D] objects, e.g. desktop manufacturing · CPC title

• G05B2219/45157

  Grind optical lens · CPC title

• B24B9/148

  electrically, e.g. numerically, controlled · CPC title

• B24B13/00

  Machines or devices designed for grinding or polishing optical surfaces on lenses or surfaces of similar shape on other work; Accessories therefor (edging optical work, e.g. lenses, prisms B24B9/14) · CPC title