Method for manufacturing an ophthalmic lens comprising a marking step for producing permanent technical marks on said ophthalmic lens
10459247 ยท 2019-10-29
Assignee
Inventors
Cpc classification
B29C64/106
PERFORMING OPERATIONS; TRANSPORTING
B33Y10/00
PERFORMING OPERATIONS; TRANSPORTING
G02C7/021
PHYSICS
B33Y30/00
PERFORMING OPERATIONS; TRANSPORTING
B29D11/00317
PERFORMING OPERATIONS; TRANSPORTING
B33Y80/00
PERFORMING OPERATIONS; TRANSPORTING
B29D11/00432
PERFORMING OPERATIONS; TRANSPORTING
B33Y40/20
PERFORMING OPERATIONS; TRANSPORTING
B29C64/124
PERFORMING OPERATIONS; TRANSPORTING
International classification
B33Y10/00
PERFORMING OPERATIONS; TRANSPORTING
B33Y80/00
PERFORMING OPERATIONS; TRANSPORTING
B29C64/124
PERFORMING OPERATIONS; TRANSPORTING
B29C64/106
PERFORMING OPERATIONS; TRANSPORTING
B29D11/00
PERFORMING OPERATIONS; TRANSPORTING
B33Y30/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A method for manufacturing an ophthalmic lens (12), includes a marking step for producing permanent technical marks (24) on the lens, which includes a body (29), a first surface (20) and a second surface (28) opposite the first surface (20); the step of additive manufacturing (110-112) of the body and the first and second surfaces, by depositing a plurality of first predetermined volume elements of a first material having a first complex index of refraction (35), in order to obtain first and second optical surfaces, respectively, of the first and second surfaces; and the step of additive manufacturing (113) of the marks by depositing, during the deposition of a plurality of the first volume elements of the first material, at least one second predetermined volume element of a second material having a second complex index of refraction (30) other than the first complex index of refraction of the first material.
Claims
1. A method for manufacturing an ophthalmic lens, the method comprising: a marking operation for producing technical permanent marks on said ophthalmic lens that exhibits a body, a first face, and a second face opposite to said first face, the first face and the second face respectively defining a first optical surface and a second optical surface, the marking operation comprising additively manufacturing said body and said first and second faces, by depositing a plurality of first predetermined volume elements of a first material having a first complex refractive index, to obtain said first and second optical surfaces, and additively manufacturing said technical permanent marks by depositing, during said depositing the plurality of said first predetermined volume elements of said first material, at least one second predetermined volume element of a second material having a second complex refractive index different from said first complex refractive index of said first material, the technical permanent marks being located in a zone of the ophthalmic lens passing through a horizontal axis, on either side and at an equal distance from a reference point, wherein the technical permanent marks are characteristic of an optical reference system to be provided to said ophthalmic lens and are located in said ophthalmic lens in a determined position dependent on said first and second optical surfaces, the technical permanent marks are additively formed in a plurality of successive and superposed layers of the first material, wherein at least two of the technical permanent marks are in a same layer, and the first face and the second face are curved, the first face being convex and the second face being concave, the plurality of superposed layers between the first face and the second face being flat layers in a direction perpendicular to a vertical axis passing through the first face and the second face.
2. The method as claimed in claim 1, wherein the additively manufacturing the body and the first and second faces comprises determining a manufacturing setting for said ophthalmic lens, the manufacturing setting comprising geometric characteristics of said body and said first and second faces and geometric characteristics of said technical permanent marks which are dependent on said geometric characteristics of said body and on said first and second faces and on said first complex refractive index.
3. The method as claimed in claim 2, wherein said additively manufacturing said technical permanent marks is carried out upon the depositing the plurality of said first volume elements of said first material during the additive manufacture at least of said body of said ophthalmic lens.
4. The method as claimed in claim 2, wherein said additively manufacturing said technical permanent marks is carried out upon the depositing the plurality of said first volume elements of said first material during the additive manufacture at least of one of said first and second faces of said ophthalmic lens.
5. The method as claimed in claim 2, wherein said determined position and said geometric characteristics of said technical permanent marks are dependent on the distance, zero or non-zero, separating the technical permanent marks from said first and second faces.
6. The method as claimed in claim 5, wherein said additively manufacturing said technical permanent marks is carried out upon the depositing the plurality of said first volume elements of said first material during the additive manufacture at least of said body of said ophthalmic lens.
7. The method as claimed in claim 5, wherein said additively manufacturing said technical permanent marks is carried out upon the depositing the plurality of said first volume elements of said first material during the additive manufacture at least of one of said first and second faces of said ophthalmic lens.
8. The method as claimed in claim 1, wherein said additively manufacturing said technical permanent marks is carried out upon the depositing the plurality of said first volume elements of said first material during the additive manufacture at least of said body of said ophthalmic lens.
9. The method as claimed in claim 8, wherein said technical permanent marks are produced in said body of said ophthalmic lens, as close as possible to at least one of said first and second faces of said ophthalmic lens.
10. The method as claimed in claim 1, wherein said additively manufacturing said technical permanent marks is carried out upon the depositing the plurality of said first volume elements of said first material during the additive manufacture at least of one of said first and second faces of said ophthalmic lens.
11. The method as claimed in claim 1, wherein said technical permanent marks are produced at least as close as possible to a face of said ophthalmic lens, from among said first face or said second face, which exhibits the greatest progression variation.
12. The method as claimed in claim 1, wherein said first material and said second material are configured in such a way that the difference between said first complex refractive index of said first material and said second complex refractive index of said second material is detectable.
13. The method as claimed in claim 1, further comprising providing a manufacturing file characteristic of a geometry of said body and of said first and second faces and said technical permanent marks of said ophthalmic lens, said geometric characteristics of said technical permanent marks being dependent on said geometric characteristics of said body and said first and second faces and said first complex refractive index.
14. The method as claimed in claim 1, further comprising polishing at least one of said first and second faces of said ophthalmic lens.
15. The method as claimed in claim 1, wherein the technical permanent marks are microcircles.
16. The method as claimed in claim 1, wherein the horizontal axis is a nasal-temporal axis.
17. The method as claimed in claim 1, wherein the reference point is situated at a center of the ophthalmic lens.
18. A method for manufacturing an ophthalmic lens, the method comprising: a marking operation for producing technical permanent marks on said ophthalmic lens that exhibits a body, a first face, and a second face opposite to said first face, the first face and the second face respectively defining a first optical surface and a second optical surface, the marking operation comprising additively manufacturing said body and said first and second faces, by depositing a plurality of first predetermined volume elements of a first material having a first complex refractive index, to obtain said first and second optical surfaces, and additively manufacturing said technical permanent marks by depositing, during said depositing the plurality of said first predetermined volume elements of said first material, at least one second predetermined volume element of a second material having a second complex refractive index different from said first complex refractive index of said first material, the technical permanent marks being located in a zone of the ophthalmic lens passing through a horizontal axis, on either side and at an equal distanced from a reference point, the technical permanent marks being at least alignment reference markings comprising two marks located 34 mm apart, equidistant to a vertical plane through a fitting point or prism reference point, wherein the technical permanent marks are characteristic of an optical reference system to be provided to said ophthalmic lens and are located in said ophthalmic lens in a determined position dependent on said first and second optical surfaces, the technical permanent marks are additively formed in a plurality of successive and superposed layers of the first material, wherein at least two of the technical permanent marks are in a same layer, and the first face and the second face are curved, the first face being convex and the second face being concave, the plurality of superposed layers between the first face and the second face being flat layers in a direction perpendicular to a vertical axis passing through the first face and the second face.
Description
BRIEF DESCRIPTION OF THE DRAWING FIGURES
(1)
(2)
(3)
(4)
(5)
(6)
DETAILED DESCRIPTION OF THE INVENTION
(7)
(8) This additive manufacturing machine 1 is here configured to deposit by juxtaposition a plurality of predetermined volume elements forming superposed layers (stated otherwise layer by layer), of at least one material on a support 10 so as to form an ophthalmic lens 12, including an ophthalmic lens of the type known as progressive possessing furthermore toric and prismatic components.
(9) Each volume element is defined by a predetermined composition and a predetermined size.
(10) As one is dealing here with additive manufacture and in particular with three-dimensional printing, one also speaks of volumetric element, or volume element, also called a voxel (representative of a pixel in three dimensions).
(11) Accordingly, the additive manufacturing machine 1 comprises a nozzle or a bank of nozzles 13 as well as a command and control unit 2 provided with a data processing system comprising a microprocessor 3 furnished with a memory 4, in particular nonvolatile, allowing it to load and store an item of software, stated otherwise a computer program which, when it is executed in the microprocessor 3, allows the implementation of an additive manufacturing method. This nonvolatile memory 4 is for example of ROM (Read-Only Memory) type.
(12) The unit 2 furthermore comprises a memory 5, in particular volatile, making it possible to store data during the execution of the software and the implementation of the additive manufacturing method.
(13) This volatile memory 5 is for example of RAM or EEPROM type (respectively Random Access Memory and Electrically Erasable Programmable Read-Only Memory).
(14) The additive manufacturing machine 1 comprises moreover an opening 6, here glazed, configured so as to access the ophthalmic lens 12 additively manufactured by this machine 1, which ophthalmic lens 12 is carried by the support 10.
(15) It will be noted that in order to additively manufacture the ophthalmic lens 12, precise knowledge is needed of certain parameters of additive manufacture, such as the speed of advance of the nozzle or nozzles 13, the energy and energy source implemented, here a source emitting in the ultraviolet for the three-dimensional printing machine but it could be a laser in the case of a stereolithography machine or else a heating energy in the case of tensioned thread deposition also called thermoplastic thread extrusion.
(16) Precise knowledge is also needed of the material or materials used and their state, here in liquid form.
(17) Precise knowledge is also needed of the geometry of the ophthalmic lens 12, which is characterized by a manufacturing file characteristic at one and the same time of the simple or complex optical properties of the ophthalmic lens 12 and of the technical permanent marks 24 (
(18) It will be noted that these technical permanent marks 24 make it possible in particular to correctly position the ophthalmic lens 12 for posterior steps of manufacture of this ophthalmic lens 12; for example surfacing and/or polishing and/or edging of this lens.
(19) It will be noted that other marks 21 to 23, which are temporary and technical, also make it possible to correctly position the ophthalmic lens 12.
(20)
(21) This ophthalmic lens 12 exhibits a first face 20 known as the front face, which is convex here, as well as a second face 28 (
(22) The first face 20 defines a first optical surface while the second face 28 defines a second optical surface.
(23) The ophthalmic lens 12 furthermore exhibits a peripheral edge 27 joining the first face 20 to the second face 28.
(24) Here this ophthalmic lens 12 exhibits technical permanent marks 24 and technical temporary marks 21 to 23, namely a mark indicating a reference point 21 situated at the center of this ophthalmic lens 12, a mark indicating a control point 22 of a far vision zone and which is situated just above the reference point 21, a control point 23 of a near vision zone and which is situated below the reference point 21 and a zone 24 passing through a horizontal axis known as nasal-temporal axis (or nose-ear axis).
(25) The marks visible in
(26) In the present case these technical permanent marks 24 are made on the first face 20 of the ophthalmic lens 12.
(27) It will be also noted that at the level of the zone 24 passing through the horizontal axis known as nasal-temporal axis are made two permanent microcircles on either side of the reference point 21 and each at equal distance from the latter.
(28) The ophthalmic lens 12 and in particular the position of the technical microcircles 24 in this ophthalmic lens 12 will now be described in greater detail with reference to
(29)
(30) The useful zone 26 is the zone of the ophthalmic lens 12 which is intended to be situated in a spectacle frame when this lens 12 is shaped to the form of the frame and is mounted in the latter. In particular, this useful zone 26 exhibits at least one part having simple optical characteristics (simple vision ophthalmic lens) or complex optical characteristics (progressive ophthalmic lens) necessary to provide a correction to the wearer.
(31) The non-useful zone 25 is for its part intended to disappear in particular during the edging step, also termed cutting, for adapting the shape (the outline) of the ophthalmic lens 12 to the spectacles frame. It will be noted that the method described hereinafter may be configured to manufacture ophthalmic lenses without a non-useful zone, that is to say directly in the shape adapted to the frame (and not therefore requiring any edging or cutting step).
(32) It is also seen in
(33) It will be noted that on this cross-section is shown only the useful zone 26 of the ophthalmic lens 12, which therefore comprises an edged peripheral outline 40, that is to say cut to the shape of the frame, independently of the method used to obtain this edged peripheral outline.
(34) The ophthalmic lens 12 is formed here by a plurality of superposed layers of a first material 35, each layer being itself formed of a plurality of first predetermined volume elements.
(35) This plurality of superposed layers forms the body 29 together with the second face 28 and the first face 20 of the ophthalmic lens 12.
(36) It will be observed that, even though here the ophthalmic lens 12 is already edged, the superposed layers of the first material 35 exhibit different lengths so as to form the first and second faces 20 and 28 of this ophthalmic lens 12.
(37) These layers here each exhibit a constant thickness over their length and they all exhibit the same thickness.
(38) It will be noted that this equi-thickness is obtained here by virtue of the controlled diffusion, by the nozzle or the bank of nozzles 13 of the manufacturing machine 1, of a determined quantity of first predetermined volume elements for each superposed layer of the first material 35.
(39) It will be noted that here the first material is an acrylic polymer, and more precisely a photopolymer, for example a photopolymer such as the product marketed by the company OBJET Ltd, under the trademark VeroClear, having a refractive index equal to about 1.5.
(40)
(41) It will be noted that here these technical microcircles 24 are made as close as possible to the first face 20 since this is the most complex face of the ophthalmic lens, that is to say, in the case of a progressive lens, the face which exhibits the greatest progression (stated otherwise the largest difference in altitude, ignoring toric and spherical components, if any).
(42) Here (
(43) Accordingly, the ophthalmic lens 12 comprises several predetermined volume elements of a second material 30, disposed in the thickness of several of the layers of the first material 35.
(44) The technical microcircle 24 made on the left in
(45) The technical microcircle 24 made on the right in
(46) Each technical microcircle 24 forming a permanent mark is manufactured here additively by the deposition, during the deposition of two superposed and successive layers of the first material 35, of a determined number of predetermined volume elements of the second material 30.
(47) It will be noted that the second material 30 is here an acrylic polymer comprising colloidal particles of Zirconia ZrO2 and having a second complex refractive index of about 1.53.
(48) The first material 35 therefore presents a complex refractive index different from the complex refractive index of the second material 30 and more precisely, the difference between these complex refractive indices is here of the order of about 0.03, the values of the extinction coefficients being zero.
(49) This complex refractive index difference makes it possible for these microcircles 24 forming technical permanent marks to be rendered visible for example by an optician albeit without bothering the vision of the wearer of this ophthalmic lens 12.
(50) These technical microcircles 24 are detectable for example by illumination and detection devices.
(51) It will be noted that the visibility of the technical microcircles 24 is dependent in particular on their geometry, which geometry is defined by the number of second predetermined volume elements of the second material 30 and the arrangement of these second predetermined volume elements with respect to one another and with respect to the first predetermined volume elements of the first material 35.
(52) The steps of additive manufacture of the ophthalmic lens 12 which has just been described, by virtue in particular of the additive manufacturing machine 1 illustrated in
(53)
(54) The command and control unit 2 is configured to determine a manufacturing setting for the ophthalmic lens 12, which setting comprises the geometric characteristics of the body 29 and of the first and second faces 20 and 28 and the geometric and positioning characteristics of the technical permanent marks 24 which are dependent on the geometric characteristics of the body 29 and the first and second faces 20 and 28 and the first complex refractive index.
(55) It will be noted that the geometric characteristics of the body 29 and of the first and second faces 20 and 28, together with the first complex refractive index, define an invisible optical reference system of the lens, while the geometric and positioning characteristics of the technical permanent marks 24 define a visible optical reference system of the lens, illustrating the invisible optical reference system.
(56) The determined position and the geometric characteristics of the technical permanent marks 24 are in particular dependent on the distance, zero or non-zero, separating them from the first and second faces 20 and 28.
(57) The command and control unit 2 is configured to provide in step 100 a manufacturing file characteristic of the geometry and technical permanent marks 24 incorporated in the ophthalmic lens 12 to be manufactured, which manufacturing file is generated on the basis of the previously determined manufacturing setting.
(58) Here this is a manufacturing file characteristic of the geometry of the body 29 and of the first and second faces 20 and 28 as well as of all the technical permanent marks of the ophthalmic lens 12, which technical permanent marks 24 are characterized (in terms of position) as a function of the geometric characteristics of the body 29 and of the first and second faces 20 and 28 and of the first complex refractive index in which this body 29 and these faces 20 and 28 are produced. It will be noted that this file takes into account all the optical functions prescribed for the ophthalmic lens 12, be they simple or progressive with or without toric or indeed prismatic components.
(59) This manufacturing file comprises geometric surface characteristics at a finite number of points, as well as the material characteristics.
(60) The command and control unit 2 is thereafter configured to determine on the basis of the manufacturing file received in step 100, the number of first predetermined volume elements and the number of layers of the first material 35 to be deposited successively in a superposed manner, as well as the number of second predetermined volume elements of second material 30 to be deposited and the location at which to deposit them during the deposition of the first predetermined volume elements of the first material 35.
(61) The method thereafter comprises step 101 of additively manufacturing the ophthalmic lens 12 provided with the geometric, optical characteristics and with the technical permanent marks 24 in the body 29 and the first and second faces 20 and 28 of this ophthalmic lens 12.
(62) More precisely, the method comprises here simultaneously steps 110, 111 and 112 (
(63) The method furthermore comprises step 113 of additively manufacturing the technical permanent marks 21 to 24 of the ophthalmic lens 12 at the same time as any one of steps 110, 111 and 112 of additive manufacture respectively of the second face 28, of the body 29 and of the first face 20 of the ophthalmic lens 12.
(64) The method can furthermore comprise a step 102 of polishing the additively manufactured ophthalmic lens 12.
(65) Here, the method is configured to manufacture the ophthalmic lens 12 directly in the shape of the frame and does not require any edging or cutting. As a variant, the method also comprises a step of edging or cutting the ophthalmic lens to the shape of the frame.
(66) It will be noted that here the additive manufacturing machine illustrated in
(67) Variant embodiments of the ophthalmic lens 12 will now be described with reference to
(68)
(69) It will be observed that the references used in
(70) In
(71) Here the microcircles are each additively manufactured in the thickness of the two same layers of the first material 35 during the additive manufacture of the body 29 and of the second face 28 of this ophthalmic lens 12.
(72) These microcircles forming technical permanent marks are formed in the same manner as previously, that is to say by the deposition of a determined number of predetermined volume elements of the second material 30 at the time of the deposition of the layers of the first material 35.
(73) Here the first and second materials are identical to those described previously.
(74)
(75) These microcircles are disposed remote both from the first face 20 and from the second face 28 of this ophthalmic lens 12.
(76) As previously, the first material 35 and the second material 30 are identical to those described hereinabove.
(77) Here the microcircles forming technical permanent marks are manufactured additively by depositing a determined number of predetermined volume elements of the second material 30 during the deposition (that is to say at the same time) of a single layer of the first material 35.
(78)
(79) Here the second material 31 is a material also known as fluorescent, for example a polymer formulation comprising molecules from the family of the Coumarins.
(80) In the ophthalmic lens 12 illustrated in
(81) In variants that are not illustrated: the technical permanent marks are not made at the sites illustrated in
(82) It is recalled more generally that the invention is not limited to the examples described and represented.