METHOD FOR PRODUCING AT LEAST ONE SPECTACLE LENS

Description

DOMAINE DE L'INVENTION

[0001] The invention relates to the field of manufacturing ophthalmic lenses having at least one optical function, for example progressive ophthalmic lenses.

[0002] The invention relates more particularly to a method of manufacturing such ophthalmic lenses.

[0003] The invention also relates to a machine for manufacturing such ophthalmic lenses. ARRIERE PLAN TECHNOLOGIE

[0004] It is known that ophthalmic lenses undergo different manufacturing stages in order to provide them with the prescribed ophthalmic properties (also called optical function).

[0005] Methods for manufacturing ophthalmic lenses are known which include a step of providing a raw or semi-finished disc, i.e. a disc having no or only one so-called finished face (in other words a face which defines a simple or complex optical surface).

[0006] These processes then include one or more steps of machining at least one face of the puck, called raw, to obtain a face called finished, defining the optical surface sought to provide the ophthalmic properties (complex or not) prescribed to the wearer of the ophthalmic lens.

[0007] One or more machining steps are understood to mean the so-called roughing, finishing and polishing steps (surface machining).

[0008] The optical function of an ophthalmic lens is provided mainly by two diopters corresponding to the front and rear faces of the ophthalmic lens. The topography of the surface to be produced depends on the distribution of the applied function between the front and rear faces of the lens.

[0009] The roughing step allows, starting from a raw or semi-finished puck, to give it the thickness and the radii of curvature of the surface on the so-called unfinished face(s) of the puck, while the finishing step (also called smoothing) consists of refining the grain or even the precision of the radii of curvature of the faces obtained previously and allows to prepare (smooth) the curved surface(s) generated for the polishing step. This polishing step is a surfacing step of the smoothed or roughed curved surface(s), and allows to make the ophthalmic lens transparent. The roughing and finishing steps are steps which impose the thickness of the final lens and the radii of curvature of the treated surface independently of the thickness of the initial object and its initial radii of curvature.

[0010] It should be noted that a technology for manufacturing complex optical surfaces, called "free form surfacing" or "digital surfacing" in English, involves particularly precise machining, such a surface combining for example a torus and a progression. The machining of such a complex optical surface is carried out using at least one very high precision machining machine at least for the roughing step, or even for the finishing and polishing step, and / or a polisher capable of polishing the surface(s) resulting from the previous steps, without deforming the ophthalmic lens.

[0011] Document WO2006 / 029268A2 discloses the additive manufacturing (3D printing) of an optical complementary element on a spectacle lens blank. OBJET DE L'INVENTION

[0012] The invention aims to provide a method for manufacturing an ophthalmic lens having at least one optical function, which is particularly simple, convenient and economical to implement, and which is also capable of quickly and flexibly providing lenses having very diverse geometries, ophthalmic properties and material characteristics, responding to a logic of mass customization.

[0013] The invention thus relates to a method for manufacturing at least one ophthalmic lens and an additive manufacturing machine configured to manufacture such an ophthalmic lens, as defined in the claims.

[0014] In a manner useful for understanding the invention, there is described in the present document a method of manufacturing at least one ophthalmic lens having at least one optical function, characterized in that it comprises: the step of providing a starting optical system of said at least one ophthalmic lens, having a basic optical function provided by a front face and a rear face of said starting optical system; and the step of additively manufacturing a complementary optical element of said at least one ophthalmic lens, by depositing a plurality of predetermined volume elements of at least one material having a predetermined refractive index, directly on at least one of said front face and rear face of said starting optical system;with said additive manufacturing step which comprises the step of determining a manufacturing instruction for said complementary optical element from characteristics of said at least one optical function to be provided to said at least one ophthalmic lens, characteristics of said at least one basic optical function of said starting optical system, geometric characteristics of said starting optical system and said predetermined refractive index of said at least one material.;

[0015] The method according to the invention thus makes it possible to obtain an ophthalmic lens formed from a starting optical system, also called a base lens, and a complementary optical element, also called an optical overthickness, directly manufactured in an additive manner on the starting optical system. The term "directly" means that there is no intermediate part (such as, for example, a manufacturing support of an additive manufacturing machine) between the starting optical system and the complementary optical element, neither during its manufacture nor once the ophthalmic lens has been manufactured. It will be noted that a predetermined treatment can be carried out on the face(s) of the starting optical system on which an overthickness can be manufactured, this treatment being configured to facilitate the attachment of the material forming the complementary optical element, without it being an intermediate part.This treatment may be one or more treatments among physical or chemical surface activation treatments, such as for example, corona, plasma, alcoholic or sodium solution, actinic source. Similarly, the starting optical system may comprise a bonding layer and / or may comprise at least one layer making it possible to carry out an optical impedance adaptation between the starting optical system and the complementary optical element when these have different refractive indices.

[0016] It should be noted that by ophthalmic lens we mean here an optical lens of ophthalmic quality intended to be mounted on a frame of a pair of glasses. This may be an ophthalmic lens in the shape of the frame or requiring a further trimming step, or even integral with the frame. It may thus be a single-vision, bifocal, multifocal, or progressive lens, or even a single ophthalmic lens intended to be opposite the right eye and the left eye, such ophthalmic lenses being known in particular under the name mask or visor.

[0017] The face (front or back) of the starting optical system on which the complementary optical element is directly manufactured is at least partially curved and therefore has a curvature or radii of curvature on its surface.

[0018] It will be noted that the starting optical system may comprise a frame capable of receiving two separate ophthalmic lenses, each intended to be opposite the right eye and the left eye, or a frame capable of receiving a single ophthalmic lens intended to be opposite the right eye and the left eye (mask or visor). It will be noted that within the framework of the invention, the optical system comprising at least one frame and at least one ophthalmic lens may be manufactured separately or integrally.

[0019] It should be noted that this additional optical element may include, for example, an extra thickness manufactured on one of the front or rear faces of the initial optical system, or an extra thickness manufactured on the front face and an extra thickness manufactured on the rear face of the initial optical system.

[0020] It should be noted that since the ophthalmic lens is the result of the combination of the starting optical system and the complementary optical element, the properties inherent to this system and this element are found in the ophthalmic lens. Thus, it is, for example, particularly advantageous to choose a starting optical system with predetermined properties to bring them to the lens. Il may for example be a starting optical system having a predetermined rigidity and / or formed from a material having high temperature resistance properties.

[0021] Thanks to the method according to the invention, it is not necessary to manufacture the entire ophthalmic lens by additive manufacturing. This method thus makes it possible, thanks to the use of the starting optical system preferably manufactured using conventional techniques (for example molding and possibly machining), to optimize the quantity of material used in additive manufacturing to obtain the ophthalmic lens. In addition, the materials forming the starting optical system and the complementary optical element can be chosen with different respective refractive indices so as to optimize (reduce) the thickness of the complementary optical element and thus further optimize the quantity of material used in additive manufacturing to obtain the ophthalmic lens.In addition, it is thus possible to update a wearer's prescription while allowing them to retain the other function(s) of their original optical system, for example special treatments such as photochromic treatments or a polarized filter or, in the case of active lenses, to be able to retain the settings and / or the active system.

[0022] The manufacturing method according to the invention therefore makes it possible to obtain an ophthalmic lens having an optical function resulting from the combination of a basic optical function (zero or non-zero) of the initial optical system and a complementary optical function (non-zero, simple or complex, and potentially additional) of the complementary optical element.

[0023] A simple optical function can be defined as the optical function obtained from spherical or toric surfaces.

[0024] Conversely, it is possible to define a complex optical function as being the optical function obtained from at least one non-simple surface, that is to say for example an aspherical, atoric surface, comprising a function associated with mounting, or even with unbasing ("freecurve" in Anglo-Saxon terminology).

[0025] Furthermore, it is possible to define an additional optical function as an optical function which has a continuous or non-continuous variation in power, depending on the position on the lens, and / or depending on time. This can be, for example, a progressive or multifocal optical function, such as bifocal or trifocal, or with power controlled over time, as for example can be the case for a fluidic lens or a lens comprising an active function or an informative lens.

[0026] It should be noted that it is the complementary optical element that makes it possible to obtain the desired optical function for the ophthalmic lens from the original optical system, even if the original optical system already has an optical function. In other words, without this complementary optical element, the ophthalmic lens cannot have the optical function prescribed for it. This complementary optical element therefore has nothing to do with a simple surface coating, such as a layer of anti-reflective coating, anti-fog coating, anti-scratch coating or even anti-fouling coating.

[0027] It should be noted that in the context of the present invention, which is in the field of ophthalmics, the optical function to be provided to the ophthalmic lens makes it possible to correct aberrations, that is to say defects of an optical system, namely the eye of the wearer of the ophthalmic lens, which are here only of the so-called lower order. In other words, the optical function to be provided to the ophthalmic lens must make it possible at least to correct aberrations of the lower order and is not limited to making it possible to correct aberrations of the so-called higher order.

[0028] In practice, in the field of ophthalmics, the ophthalmic properties prescribed to the wearer of the ophthalmic lens, which define the optical function to be provided to this lens, are generally expressed in diopters (D) and are quantified in increments of 0.25 D.

[0029] It will be noted that during the manufacture of such ophthalmic lenses, manufacturing tolerances of the order of 0.06 D to 0.12 D are generally accepted. Thus, in the ophthalmic field, the power to be provided is at least greater than 0.06 D, preferably greater than 0.12 D, for example within the interval [0.12 D; 12 D], and preferably within the interval [0.25 D; 5 D].

[0030] It should also be noted that the optical power, or the carrier power, thus obtained once the optical function has been provided to the ophthalmic lens, is calculated from measurements generally taken in accordance with standard ISO_10322-2(F) using a frontofocometer, i.e. with an analysis pupil of the frontofocometer of at least approximately 3 to 5 mm.

[0031] Additive manufacturing techniques are particularly relevant to meet the objective of the invention.

[0032] Additive manufacturing, according to the international standard ASTM 2792-12, means manufacturing techniques comprising a process for joining materials in order to manufacture objects from 3D modeling data (typically a computer-aided design file, hereinafter CAD) usually representing a layer-by-layer design, as opposed to subtractive manufacturing methodologies, such as traditional machining.

[0033] Additive manufacturing corresponds here, for example, to a three-dimensional printing process using, for example, a jet of polymer material ("inkjet printing" in English terminology), or a stereolithography process, or even stereolithography by mask projection, or even a sintering or selective laser melting process ("Selective Laser Melting", hereinafter SLM, or "Selective Laser Sintering", hereinafter SLS in English terminology), or even a thermoplastic wire extrusion process.

[0034] Additive manufacturing technologies involve manufacturing objects by juxtaposing material elements according to a predefined arrangement in digital form in a CAD file. The material constituting the volume elements in additive manufacturing can be solid, liquid, or gel-like, although it is common for the material to be essentially solid at the end of the additive manufacturing process.

[0035] These elementary volume elements called "voxels" can be created and juxtaposed according to a variety of different technical principles, for example, by depositing drops of photopolymerizable monomers using a printing nozzle, by selective photopolymerization with an ultraviolet source on the surface of a monomer bath (stereolithography technique), or by polymer powder fusion (SLM).

[0036] It will be observed that the starting optical system as such forms a manufacturing support for the complementary optical element. Here, the manufacturing support therefore does not belong to the additive manufacturing machine, which comprises a receiving support intended to receive the starting optical system. Thus, the manufacturing support (starting optical system) is distinct from the receiving support, which is not intended to be part of the ophthalmic lens.

[0037] The manufacturing method according to the invention is therefore particularly simple, convenient and economical, especially in a context where the diversity of optical functions to be produced is significant (due to the customization of these optical functions), requiring rapid and flexible manufacturing methods.

[0038] It should also be noted that the optical function of a lens, system or optical element is understood to mean the optical response of this lens, system or element, i.e. a function defining any modification of propagation and transmission of an optical beam through the lens, system or optical element concerned, for any incidence of the incoming optical beam and over the entire geometric extent of an input diopter illuminated by the incident optical beam.

[0039] More precisely, in the ophthalmic field, the optical function is defined as the distribution of the characteristics of wearer power, astigmatism, prismatic deviations associated with the lens, system or optical element for all directions of gaze of a wearer of this lens, system or element. This of course presupposes the predetermination of the geometric positioning of the lens, system or optical element in relation to the wearer's eye.

[0040] According to preferred, simple, convenient and economical characteristics of the process: said additive manufacturing step comprises the step of determining geometric characteristics of said complementary optical element and / or of said at least one ophthalmic lens from characteristics of at least one complementary optical function to be provided to said complementary optical element, said geometric characteristics of said starting optical system and said predetermined refractive index of said at least one material; said additive manufacturing step comprises the step of determining at least one complementary optical function to be provided to said complementary optical element from said characteristics of said at least one optical function to be provided to said at least one ophthalmic lens and said characteristics of said at least one basic optical function of said starting optical system; said step of additively manufacturing comprises the step of determining said at least one optical function to be provided to said at least one ophthalmic lens from prescription values ​​linked to a wearer of said at least one ophthalmic lens and additional data on wearing a predetermined frame and / or personalization and / or shape of the frame; said step of additively manufacturing comprises the step of measuring said characteristics of said at least one basic optical function of said starting optical system and / or the step of measuring said geometric characteristics of said starting optical system; said at least one material in which said complementary optical element is additively manufactured is different from the material constituting said starting optical system;said starting optical system is formed by an assembly comprising a frame and two initial ophthalmic lenses mounted on said frame, and said method comprises a step of additive manufacturing of two said complementary optical elements respectively on said initial ophthalmic lenses used as starting optical system to form two said ophthalmic lenses, with said manufacturing instruction which is further determined from characteristics linked to the binocular vision of a wearer of the two said ophthalmic lenses; said additive manufacturing step preferably implements a three-dimensional printing process, or stereolithography, or stereolithography by mask projection, or even sintering or selective laser melting, or extrusion by thermoplastic wire;said additive manufacturing step is carried out by depositing a plurality of at least one element of predetermined volume of said at least one material on at least the entire useful surface of at least one of said front face and rear face of said starting optical system; the method comprises, before said additive manufacturing step, the step of introducing and positioning said starting optical system on a receiving support in an additive manufacturing machine; the method comprises, after said step of positioning said starting optical system and before said additive manufacturing step, the step of checking the position of said starting optical system in said additive manufacturing machine and the step of triggering a corrective action if there is a difference between the actual position of said starting optical system and a predetermined position;after said additive manufacturing step, said complementary optical element and / or said starting optical system have a contour substantially equal to a contour configured to be introduced into a predetermined frame; the method comprises, after the additive manufacturing step, the step of irradiating said ophthalmic lens; and / or the method comprises the step of treating and / or varnishing at least one face of said ophthalmic lens.;

[0041] In a manner useful for understanding the invention, there is further described in the present specification an additive manufacturing machine configured to manufacture an ophthalmic lens and comprising a control and command unit provided with systemic elements configured to execute a computer program comprising instructions configured to implement each of the steps of the manufacturing method described above.

[0042] According to preferred, simple, convenient and economical features of the machine: the machine comprises a receiving support configured to receive said starting optical system, with said receiving support and / or said starting optical system being configured so that the latter is positioned in a predetermined position relative to a reference frame of said machine; and / or the machine comprises a detection system, formed for example by an optical reading device and / or an image capture device, configured to detect the position of said starting optical system on said receiving support and / or relative to said predetermined position in said reference frame of said machine. BREVE DESCRIPTION DES DESSINS

[0043] We will now continue the description of the invention by describing an exemplary embodiment, given below for illustrative and non-limiting purposes, with reference to the appended drawings in which: there figure 1 schematically represents an additive manufacturing machine configured to produce at least one complementary optical element directly on a starting optical system to obtain at least one ophthalmic lens; the figure 2 schematically represents a starting optical system and an ophthalmic lens comprising this starting optical system and obtained at least partially using the machine illustrated in the figure 1 ; THE figures 3 à 5 are views similar to that of the figure 2 , illustrating different variants of the production of ophthalmic lenses; the figure 6 is a block diagram illustrating different operating steps of a process for manufacturing an ophthalmic lens; and the figure 7 is a block diagram illustrating other operating steps of the method of manufacturing at least one ophthalmic lens. DESCRIPTION DETAILLEE D'UN EXEMPLE DE REALISATION

[0044] There figure 1 illustrates an additive manufacturing machine 1 of an ophthalmic lens 12, here a digitally controlled three-dimensional printing machine.

[0045] Numerical control refers to all the hardware of the additive manufacturing machine 1 configured to give movement instructions to all the components that make up this machine.

[0046] The additive manufacturing machine 1 is here configured to deposit, by juxtaposition, a plurality of predetermined volume elements forming superimposed layers (in other words layer by layer), of at least one material, directly onto a starting optical system 20 and 41 ( figures 2 à 5 ) positioned on a receiving support 10 of the machine 1 to form a complementary optical element 25, 30, 35 and 47 ( figures 2 à 5 ) and thus obtain the ophthalmic lens 12.

[0047] This ophthalmic lens 12 is for example progressive and also has toric and prismatic components.

[0048] Each predetermined volume element is defined by a predetermined composition, a predetermined position in space and predetermined dimensions at a time t.

[0049] Since we are talking about additive manufacturing and for example three-dimensional printing, we also talk about a volumetric element, or volume element, also called a voxel (representative of a pixel in three dimensions).

[0050] The complementary optical element 25, 30, 35 and 47 and the starting optical system 20, 41 are configured to form the ophthalmic lens 12. It is therefore an element and a system having at least one optical function, also called “ophthalmic” in certain cases, for example progressive which may also have toric and prismatic components. Unlike the complementary optical element 25, 30, 35 and 47 which according to the invention has a non-zero complementary optical function, the starting optical system 20, 41 may comprise a zero or non-zero optical function.

[0051] Thus, the starting optical system may comprise a simple or complex optical function, or even comprise active optical elements such as a waveguide, an image guide and / or pixelated optical elements comprising cells joined or separated by walls and comprising an electroactive or photoactive composition.

[0052] The starting optical system 20, 41 is carried by the receiving support 10 while the complementary optical element 25, 30, 35 and 47 is manufactured directly on the starting optical system 20, 41, this system and this element being configured to be integral and thus form an ophthalmic lens 12 in one piece, while the latter is configured to be separated from the receiving support 10.

[0053] It will be noted that this receiving support 10 is a predetermined support of the additive manufacturing machine 1 and therefore that its geometric characteristics are known and grouped in a file which is stored or loaded into a first control and command unit 2 of the additive manufacturing machine 1.

[0054] The receiving support 10 of the additive manufacturing machine 1 comprises a body provided with a receiving surface which has an overall geometry independent or dependent, in whole or in part, on the geometry of at least one surface of the starting optical system and consequently of the ophthalmic lens 12 to be produced.

[0055] The receiving support 10 may be removable or fixed in the machine 1, or it may even be able to adapt to another machine used in addition to the additive manufacturing machine, for example a trimming machine and / or a treatment and / or varnishing machine.

[0056] It will be noted that the receiving support 10 and / or the starting optical system 20, 41 are configured so that the latter is positioned in a predetermined position on the receiving support 10 and relative to a reference of the machine 1.

[0057] Here, the receiving support 10 is for example provided with a plurality of positioning tabs (not shown), in particular at least three.

[0058] Furthermore, the machine 1 here comprises a detection system formed for example by an optical reading device (not shown) configured to detect for example an optical axis of the starting optical system.

[0059] Alternatively, the machine 1 comprises a detection system formed for example by an optical reading device and / or an image capture device (not shown), configured to detect the position of the starting optical system on the receiving support 10 and / or relative to the predetermined position in the reference frame of said machine 1.

[0060] All of the hardware and software of the additive manufacturing machine 1 is further configured to provide instructions for movement, manipulation and control of materials and polymerization devices included in this machine 1.

[0061] The additive manufacturing machine 1 comprises a nozzle or a nozzle ramp 13 as well as the control and command unit 2, which is provided with a data processing system comprising a microprocessor 3 provided with a memory 4, in particular non-volatile, allowing it to load and store software, in other words a computer program which, when executed in the microprocessor 3, allows the implementation of an additive manufacturing process. This non-volatile memory 4 is for example of the ROM type (" Read-Only Memory » in English).

[0062] Unit 2 further 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 process.

[0063] This volatile memory 5 is for example of the RAM or EEPROM type (respectively “ Random Access Memory » And « Electrically Erasable Programmable Read-Only Memory » in English).

[0064] The additive manufacturing machine 1 further comprises an opening 6, here glazed, configured to access the ophthalmic lens 12 partially manufactured additively by this machine 1 directly on its starting optical system 20, 41, which is carried by the receiving support 10 of the latter.

[0065] It will be noted that in order to additively manufacture the complementary optical element 25, 30, 35, 47 and 50, it is necessary to know precisely certain additive manufacturing parameters, such as the feed rate of the nozzle(s) 13, the energy and the energy source used, 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 even heating energy in the case of a stretched wire deposition also called extrusion by thermoplastic wire.

[0066] We also need to know precisely the material(s) used and their state, here in the form of a polymerizable composition, or of thread, drops, or powder of thermoplastic polymer.

[0067] We also need to know precisely the simple or complex optical function(s) prescribed for the ophthalmic lens 12, an optical function which is characterized by a geometry defined in a manufacturing file characteristic of the simple or complex optical properties of the ophthalmic lens 12.

[0068] According to a variant, it is also necessary to know the wearer's personalization parameters and / or the parameters of the geometry of the frame intended to receive the ophthalmic lens 12, in order to adjust the optical function of this ophthalmic lens 12 to its final conditions of use.

[0069] Knowledge of the optical function, as well as certain customization and / or frame parameters, makes it possible to know a geometric envelope required for the ophthalmic lens 12 (also called three-dimensional external envelope). This geometric envelope defines the geometric characteristics of the ophthalmic lens (12). This three-dimensional external envelope encompasses the geometric envelope of the starting optical system 20, 41 and that(s) of the complementary optical element 25, 30, 35, 47 and 50, which can be formed of one or more additional thicknesses added to at least one face of the starting optical system 20, 41.

[0070] It is recalled that by optical function of an ophthalmic lens, an optical system or an optical element, we mean the optical response of this lens or this system or this element, that is to say a function defining any modification of propagation and transmission of an optical beam through the lens, the system or the optical element concerned, whatever the incidence of the incoming optical beam and whatever the geometric extent of an input diopter illuminated by the incident optical beam.

[0071] More precisely, in the ophthalmic field, optical function is defined as the distribution of the wearer power and astigmatism characteristics associated with the lens, system or optical element for all directions of gaze of a wearer of this lens, system or element. This of course presupposes the predetermination of the geometric positioning of the lens, system or optical element relative to the wearer's eye.

[0072] In the context of the present invention, which is in the field of ophthalmics, the optical function to be provided to the ophthalmic lens makes it possible to correct aberrations, that is to say defects of an optical system, namely the eye of the wearer of the ophthalmic lens, which are here only of the so-called lower order. In other words, the optical function to be provided to the ophthalmic lens is not limited to correcting aberrations of the so-called higher order.

[0073] In practice, in the field of ophthalmics, the ophthalmic properties prescribed to the wearer of the ophthalmic lens, which define the optical function to be provided to this lens, are generally expressed in diopters (D) and are quantified in increments of 0.25 D.

[0074] It should be noted that when manufacturing such ophthalmic lenses, manufacturing tolerances of the order of 0.06 D to 0.12 D are generally accepted.

[0075] It should also be noted that the wearer power is a way of calculating and adjusting the power of the ophthalmic lens, which is different from the frontofocometer power. The wearer power calculation ensures that the power perceived by the wearer (i.e. the power of the light beam entering the eye), once the lens is positioned in the frame and worn by the wearer, corresponds to the prescribed power. In general, at any point on the lens, particularly at the distance and near vision control points, for a progressive lens, the power measured with a frontofocometer is different from the wearer power. However, the wearer power at the optical center of a single-vision lens is generally close to the power observed with a frontofocometer positioned at this point.

[0076] There figure 2 shows, schematically, an ophthalmic lens 12, obtained from a starting optical system 20 and a complementary optical element 25 manufactured additively on the receiving support.

[0077] It will be noted that the assembly formed by the starting optical system 25 and the complementary optical element 25 forms an ophthalmic lens 12 called hybrid.

[0078] The starting optical system 20 has a body 21 provided with a first face 22, called the rear face, which is concave here, as well as a second face 23, called the front face, which is convex here.

[0079] It should be noted that the front and rear faces 22 and 23 define two diopters which will characterize the basic optical function (noted F 0 on the figure 7 ) of the starting optical system 20 of the ophthalmic lens 12.

[0080] Here, the starting optical system 20 is a so-called semi-finished spectacle lens, the front face 23 of which has a finished surface, in other words having a desired curvature or radii of curvature, and which has already undergone one or more treatments, for example an anti-scratch treatment.

[0081] This starting optical system 20 is made of a material generally used for the manufacture of ophthalmic lenses and here presents a simple non-zero optical function (it could present a complex optical function), the characteristics of this simple optical function being known and characterized in a file stored or loaded into the control and command unit 2 of the additive manufacturing machine 1.

[0082] The starting optical system 20 comprises a peripheral edge 24 connecting the rear face 22 to the front face 23.

[0083] The starting optical system 20 has here been manufactured directly with a contour adapted to a shape of a predetermined frame in which the ophthalmic lens 12 is configured to be mounted.

[0084] Alternatively, the starting optical system 20 is not directly manufactured to the frame contour but requires a trimming step to adapt its contour to the frame.

[0085] The complementary optical element 25 has a body 26 provided with a first face 27, called the rear face, which is here pseudo-concave as well as a second face 28, called the front face, which is here convex.

[0086] It should be noted that the front and rear faces 28 and 27 also define two diopters which will characterize the complementary optical function (noted F 2 on the figure 7 ) of the complementary optical element 25 of the ophthalmic lens 12, which complementary optical function here presents in particular an addition.

[0087] The complementary optical element 25 comprises a peripheral edge 29 connecting the rear face 27 to the front face 28.

[0088] Here, the complementary optical element 25 was additively manufactured on the rear face 22 of the starting optical system 20 to form the ophthalmic lens 12. Thus, the front face 28 of the complementary optical element 25 is perfectly complementary to the rear face 22 of the starting optical system 20.

[0089] The complementary optical element 25 therefore forms here a single additional thickness added to the rear face 22 of the starting optical system 20.

[0090] It will be noted that for the additive manufacturing of the complementary optical element 25, the starting optical system 20 was introduced into the machine and positioned on the receiving support with the front face 23 of the starting optical system 20 resting on one face of the receiving support.

[0091] The complementary optical element 25 was manufactured to the frame contour so that its peripheral edge 29 is in the extension of the peripheral edge 24 of the starting optical system 20.

[0092] Alternatively, the complementary optical element 25 may have a peripheral edge forming a contour slightly different from that desired for the ophthalmic lens 12, for example slightly less significant or slightly larger than a contour configured to be introduced into the predetermined frame, or comprising extensions to allow gripping or which may have another function. In the case where the complementary optical element 25 has a peripheral edge forming a contour larger than a contour of the desired edge for the ophthalmic lens 12, then it will be understood that this complementary contour is part of the excess thickness produced during the additive manufacturing step and that it is defined during the step of determining the manufacturing instruction. In an even more particular case, the contour of the complementary optical element 25 is exactly that desired for the ophthalmic lens 12.

[0093] The term "useful surface" will subsequently be used for the initial optical system and / or the complementary optical element. IlThis is a surface included in a contour corresponding to the contour of the ophthalmic lens with a shape suitable for insertion into a predetermined frame. The ophthalmic lens may be shaped to be suitable for insertion into the predetermined frame before the process, when the starting optical system already has this contour, at the start of the process, for example by a step of prior trimming of the starting optical system before the process at the step of additive manufacturing of the complementary optical element, or by trimming following the step of additive manufacturing of the complementary optical element. In all these cases, a surface of the starting optical system and / or of the complementary optical element may be identified which is intended to be included in the contour of the ophthalmic lens with a shape suitable for insertion into a predetermined frame. This specific surface is defined as being the useful surface.

[0094] It should be noted that the possibility of manufacturing an additional optical element on a starting optical system which is already in the shape suitable for insertion into a predetermined frame can make it possible, on the one hand, to reduce the risks of misalignment of the lenses which could occur during a subsequent trimming step which can be carried out in the store, and on the other hand, to reduce the stocks of semi-finished products currently required.

[0095] The complementary optical element 25 is here formed by a plurality of predetermined volume elements which are juxtaposed and superimposed to form a plurality of superimposed layers of a material 60. This plurality of superimposed layers forms the body 26 together with the rear face 27 and the front face 23 of this complementary optical element 25.

[0096] These predetermined volume elements may have different geometry and be different in volume from each other, as permitted by the implementation of an additive manufacturing process. These volume elements may also be made of a single material, or alternatively they may be formed by at least two different materials, for example having distinct refractive indices, which makes it possible to have an excess thickness with a variable refractive index.

[0097] It will be noted that the use of at least two materials having different refractive indices for the additive manufacturing of the complementary optical element 25 makes it possible to provide optimized optical and functional properties to the ophthalmic lens 12.

[0098] It will be noted that the superimposed layers of the first material 60 here have different lengths so as to form the front and rear faces 27 and 28 of the complementary optical element 25.

[0099] It will be observed that certain additive manufacturing technologies have only a relative notion of "layers", a layer then being only a set of voxels artificially deposited during the same nozzle pass or the same masking. However, the teaching of the present invention is easily transposed to these technologies.

[0100] These layers each have a substantially constant thickness along the length and they all have substantially the same thickness. It will be observed that certain additive manufacturing technologies may provide layers with variable thicknesses along the length of the layer. However, the teaching of the present invention is easily transposed to these technologies.

[0101] It will be noted that this equal thickness is obtained here thanks to the controlled and commanded deposition, by the nozzle or the nozzle ramp 13 of the additive manufacturing machine 1, of a determined quantity of predetermined volume elements for each superimposed layer of the material 60.

[0102] The material 60 is here an acrylic polymer, and more precisely a photopolymer, for example a photopolymer such as the product marketed by the company OBJET Ltd, under the brand name VeroClear ™<.

[0103] The additive manufacturing of the complementary optical element 25 may require, in addition to the deposition of the plurality of successive and superimposed layers, one or more photopolymerization steps. The photopolymerization steps may take place at the deposition of each volume element, globally after the passage of the nozzle and / or the nozzle ramp or after the deposition of each layer of material. It will also be noted, as will be seen in more detail below, that the polymerization of the complementary optical element 25 may not be completely finished at the end of its additive manufacturing.

[0104] The ophthalmic lens 12 thus obtained has a body formed of the respective bodies 21 and 26 of the starting optical system 20 and of the complementary optical element 25, a front face formed by the front face 23 of the starting optical system 20, a rear face formed by the rear face 27 of the complementary optical element 25 as well as a peripheral edge formed by the respective peripheral edges 21 and 29 of the starting optical system 20 and of the complementary optical element 25; and has the optical function (denoted F 1 on the figure 7 ) which is prescribed for him.

[0105] There figure 3 shows, schematically, a first variant of the ophthalmic lens 12, obtained from a starting optical system 20 and a complementary optical element provided with two distinct extra thicknesses 30 and 35.

[0106] The starting optical system 20 has a geometry similar to that described with reference to the figure 2 , except that it has a peripheral edge 24 which is not adapted to the contour of a predetermined frame. Furthermore, this is a raw puck, that is to say without a so-called finished face, treated with value-added type treatments such as anti-reflective treatment or anti-scratch treatment or others.

[0107] The complementary optical element comprises a first extra thickness 30 added to the front face 23 of the starting optical system 20 and a second extra thickness 35 added to the rear face 22 of the starting optical system 20.

[0108] The first excess thickness 30 has a body 31 provided with a first face 32, called the rear face, which is here concave, as well as a second face 33, called the front face, which is here convex.

[0109] It will be noted that the front and rear faces 33 and 32 also define two diopters which will characterize a first sub-function of the complementary optical function of the complementary optical element.

[0110] The first excess thickness 30 comprises a peripheral edge 34 connecting the rear face 32 to the front face 33 and manufactured directly to the contour of a predetermined frame.

[0111] Here, the first extra thickness 30 was manufactured additively on the front face 23 of the starting optical system 20. The rear face 32 of the first extra thickness 30 is perfectly complementary to the useful surface of the front face 23 of the starting optical system 20 (the useful surface being the part of this face 23 which will remain once the system 20 has been cut out and the lens 12 obtained).

[0112] It will be noted that for the additive manufacturing of the first overthickness 30, the starting optical system 20 was introduced into the machine and positioned on the receiving support with the rear face 22 of the starting optical system 20 resting on one face of the receiving support.

[0113] The first excess thickness 30 is here formed by a plurality of predetermined volume elements which are juxtaposed and superimposed to form a plurality of superimposed layers of a material 60.

[0114] This plurality of superimposed layers forms the body 31 together with the rear face 32 and the front face 33 of this first extra thickness 30.

[0115] The second extra thickness 35 has a body 36 provided with a first face 37, called the rear face, which is here concave as well as a second face 38, called the front face, which is here convex.

[0116] It will be noted that the front and rear faces 37 and 38 also define two diopters which will characterize a second sub-function of the complementary optical function of the complementary optical element.

[0117] The second extra thickness 35 comprises a peripheral edge 39 connecting the rear face 37 to the front face 38 and manufactured directly to the contour of the predetermined frame.

[0118] Here, the second extra thickness 35 was manufactured additively on the rear face 22 of the starting optical system 20. The front face 38 of the second extra thickness 35 is perfectly complementary to only a part of the rear face 22 of the starting optical system 20 (the part of this face 22 which will remain once the system 20 has been cut out and the lens 12 obtained).

[0119] The second extra thickness 35 is here formed by a plurality of predetermined volume elements which are juxtaposed and superimposed to form a plurality of superimposed layers of another material 55 distinct from the material 60 used to manufacture the first extra thickness 30.

[0120] This plurality of superimposed layers forms the body 36 together with the rear face 37 and the front face 38 of this second extra thickness 35.

[0121] It will be noted that for the additive manufacturing of the second extra thickness 35, the starting optical system 20 and the first extra thickness 30 were lifted from the receiving support 10 then replaced on the latter in the machine and positioned on the receiving support with the front face 33 of this first extra thickness 30 0 and / or with the part of the front face 23 of the starting optical system 20 which is not covered by the first extra thickness 30, which rests on one face of the receiving support.

[0122] Alternatively, the starting optical system is introduced into the machine 1 and positioned on a receiving support different from that described above, having for example holding tabs configured to hold the starting optical system by its peripheral edge. Furthermore, these holding tabs can be articulated so as to additively manufacture first one of the two overthicknesses then the other after having turned over the starting optical system-overthickness assembly.

[0123] The starting optical system 20 is then cut out so as to provide it with a new peripheral edge, in the extension of the peripheral edges 34 and 39 respectively of the first and second extra thicknesses 30 and 35, and which is adapted to the contour of the predetermined frame.

[0124] Alternatively, at least one excess thickness 30, 35 may have a surface which does not correspond to the useful surface.

[0125] In particular, when the starting optical system 20 is trimmed following the additive manufacturing step, in order to provide the system with a new peripheral edge adapted to the contour of the predetermined frame, at least one of the peripheral edges 34 and 39 respectively of the first and second excess thicknesses 30 and 35 does not correspond to the new peripheral edge. In other words, when the starting optical system has a larger surface area than the useful surface area when the complementary optical element is manufactured, at least one excess thickness may have a surface area which does not correspond to the useful surface area.

[0126] In particular, according to one embodiment, at least one of the excess thicknesses can cover the entire surface 23, respectively 22, of the starting optical system 20 on which it is deposited. Alternatively, at least a portion of the useful surface of one of the surfaces 22, respectively 23, of the starting optical system 20 is not covered by the corresponding excess thickness 30, 35.

[0127] Alternatively or in a complementary manner, at least a part of the surface 23, respectively 22, of the starting optical system 20, outside the useful surface, is covered by the corresponding excess thickness 30, 35.

[0128] Preferably, the excess thickness(es) 30 (and 35) covers at least the entire area of ​​the corresponding face which is intended to be inside the peripheral edge of the ophthalmic lens having a contour adapted to the contour of the predetermined frame. In other words, the excess thickness 30, 35 covers at least the entire useful surface of the surface 22, respectively 23, of the face of the starting optical system 20 on which it is deposited during the additive manufacturing step.

[0129] It should be noted that if the complementary optical element requires a smaller outline than the outline of the ophthalmic lens so that the latter can be mounted in the frame, then it will be understood that the excess thickness covers the entire useful surface.

[0130] Even more preferably, at least one of the excess thicknesses 30 and 35 only covers the area of ​​their corresponding face which is intended to be inside the new peripheral area. In other words, the excess thickness 30, 35 only covers the useful surface of the surface 22, respectively 23, of the face of the starting optical system 20 on which it is deposited during the additive manufacturing step.

[0131] The ophthalmic lens 12 thus obtained has a body formed of the respective bodies 21, 31 and 36 of the starting optical system 20 and of the two extra thicknesses 30 and 35 of the complementary optical element, a front face formed by the front face 33 of the first extra thickness 30 of the complementary optical element, a rear face formed by the rear face 37 of the second extra thickness of the complementary optical element as well as a peripheral edge formed by the peripheral edges of the cut-out starting optical system 20 and of the extra thicknesses 30 and 35 of the complementary optical element; and has the optical function prescribed for it.

[0132] There figure 4 shows, schematically, two ophthalmic lenses 12 in accordance with a second embodiment variant, obtained from a starting optical system 40 and two complementary optical elements 47 manufactured additively.

[0133] Here, the starting optical system 40 is formed by an assembly comprising a spectacle frame having two branches 42 and a frame 43 to which the two branches 42 are connected, as well as two base lenses 41 mounted on the frame 43 of the frame.

[0134] Each base lens 41 has a body 44 provided with a first face 45, called the rear face, which is here concave as well as a second face 46, called the front face, which is here convex.

[0135] Each base lens 41 here corresponds to so-called presentation lenses that are generally found at opticians, already mounted on presentation frames.

[0136] Thus, it will be noted that the front and rear faces 45 and 46 define two curved surfaces which characterize a basic optical function, which is here zero, of each base lens 41.

[0137] Each base lens 41 has a peripheral edge connecting the rear face 45 to the front face 46.

[0138] Each base lens 41 has a contour adapted to a predetermined frame shape in which the ophthalmic lenses 12 are configured to be mounted, since it is initially, that is to say before starting the method according to the invention, already mounted in the predetermined frame.

[0139] Each complementary optical element 47 is here similar to the complementary optical element 25 described above with reference to the figure 2 .

[0140] In particular, each complementary optical element 47 has a body provided with a first face 48, called the rear face, which is here concave as well as a second face 49, called the front face, which is here convex.

[0141] It will be noted that the front and rear faces 48 and 49 define two diopters which will characterize the complementary optical function of each complementary optical element 47 of each ophthalmic lens 12.

[0142] Each complementary optical element 47 comprises a peripheral edge connecting the rear face 48 to the front face 49.

[0143] Here, each complementary optical element 47 has been additively manufactured on the back face 49 of a respective base lens 41 to form a respective ophthalmic lens 12. Thus, the front face 49 of each complementary optical element 47 is perfectly complementary to the back face 45 of the respective base lens 41 on which the complementary optical element 47 has been manufactured.

[0144] Each complementary optical element 47 therefore forms a single additional thickness added to the rear face 45 of a respective base lens 41.

[0145] It will be noted that for the additive manufacturing of the two complementary optical elements 47, the starting optical system 40 was introduced into the machine 1 and positioned on a receiving support configured to receive and hold this system for example by the branches 42 and the frame 43 of the mount.

[0146] Each complementary optical element 47 was manufactured directly to the contour of the frame so that its peripheral edge is in the extension of the peripheral edge of a respective base lens 41.

[0147] Each complementary optical element 47 is here formed by a plurality of predetermined volume elements which are juxtaposed and superimposed to form a plurality of superimposed layers of a material 60.

[0148] This plurality of superimposed layers forms the body together with the rear face 48 and the front face 49 of each complementary optical element 47.

[0149] The two ophthalmic lenses 12 thus obtained each have a body formed from the respective bodies of a base lens 41 and a complementary optical element 47, a front face formed by the front face 26 of the respective base lens 41, a rear face formed by the rear face 48 of the respective complementary optical element 47 as well as a peripheral edge formed by the respective peripheral edges of the base lens 41 and complementary optical element 47; and have the optical function prescribed for it.

[0150] There figure 5 shows, schematically, a third variant of the ophthalmic lens 12, obtained from a starting optical system 20 and a complementary optical element 50 manufactured additively in a machine separate from that illustrated in the figure 1 This is a stereolithography machine (not shown).

[0151] The starting optical system 20 is similar to that described with reference to the figure 3 .

[0152] The starting optical system 20 is here made of a material generally used for the manufacture of ophthalmic lenses such as the allylic polymer known as CR39.

[0153] The starting optical system 20 therefore has a predetermined refractive index, for example equal to approximately 1.5.

[0154] The complementary optical element 50 has a body 51 provided with a first face 52, called the rear face, which is here concave, as well as a second face 53, called the front face, which is here convex.

[0155] It will be noted that the front and rear faces 52 and 53 also define two diopters which will characterize the complementary optical function of the complementary optical element 50 of the ophthalmic lens 12.

[0156] The complementary optical element 50 is manufactured so that it does not have a peripheral edge but rather a peripheral edge coming flush with the peripheral edge 24 of the starting optical system 20.

[0157] Here, the complementary optical element 50 was additively manufactured on the front face 23 of the starting optical system 20 to form the ophthalmic lens 12. Thus, the rear face 52 of the complementary optical element 50 is perfectly complementary to the front face 23 of the starting optical system 20.

[0158] The complementary optical element 50 therefore forms a single additional thickness added to the front face 23 of the starting optical system 20.

[0159] It will be noted that for the additive manufacturing of the complementary optical element 50, the starting optical system 20 was introduced into the stereolithography machine and positioned on its receiving support with the rear face 22 of the starting optical system 20 resting on one face of the receiving support.

[0160] The complementary optical element 50 is here manufactured according to a stereolithography process and thus formed by a plurality of predetermined volume elements which are juxtaposed and superimposed to form a plurality of superimposed layers of a material 60.

[0161] In particular, the complementary optical element 50 is produced by depositing a plurality of at least one element of predetermined volume over the entire surface of the front face 23 of the starting optical system 20 in order to obtain the peripheral edge.

[0162] The plurality of superimposed layers forms the body 51 together with the rear face 52 and the front face 53 of this complementary optical element 50.

[0163] The ophthalmic lens 12 (formed from the starting optical system 20 and the complementary optical element 50) is then cut out so as to provide it with a peripheral edge referenced 54 on the figure 5 , which is adapted to the contour of a predetermined frame.

[0164] The ophthalmic lens 12 thus obtained has a body formed of the respective bodies 21 and 51 of the starting optical system 20 and of the complementary optical element 50, a front face formed by the front face 53 of the complementary optical element 50, a rear face formed by the rear face 22 of the starting optical system 20 as well as a peripheral edge formed by the respective cut-out peripheral edges of the starting optical system 20 and of the complementary optical element 50; and has the optical function prescribed for it.

[0165] We will now describe in more detail, through the figure 6 and with reference for example to the figure 3 , a method of manufacturing an ophthalmic lens 12.

[0166] The manufacturing method comprises the step 200 of providing the starting optical system 20.

[0167] The starting optical system 20 is chosen according to the lens 12 to be manufactured and its geometry is therefore known, which geometry is characterized by a surface file which is stored or loaded into the control and command unit 2 of the additive manufacturing machine 1.

[0168] In the case where the starting optical system 20 has a non-zero basic optical function, the latter is also known and characterized directly in the surface file.

[0169] The method further comprises the step 300 of introducing the starting optical system 20 into the additive manufacturing machine 1 and of positioning it in this machine 1, in an initial position relative to a reference frame of this machine 1.

[0170] This initial position can be defined as a position in which at least one of the faces of the starting optical system must be accessible so that the complementary optical element can be manufactured there additively (the face being predetermined).

[0171] This initial position can be defined, alternatively or additionally, as being a position in which the starting optical system is centered (or at least in a predetermined position) relative to the machine reference frame.

[0172] This initial position can also be defined, alternatively or additionally, as being a position in which the starting optical system is angularly oriented, for example in the case where the latter has a non-circular contour and / or a complex optical function and / or a cylinder.

[0173] This initial position can be defined, alternatively or additionally, as being a position in which the starting optical system is inclined.

[0174] In particular, the optical departure system 20, 41 is positioned on the receiving support 10 of the machine 1.

[0175] The method optionally comprises the step 400 of checking the position of the starting optical system 20, 41 in the additive manufacturing machine 1 and the step of triggering a corrective action if there is a difference between the initial position of the starting optical system 20, 41 and a predetermined position in the reference frame of the machine 1.

[0176] This positioning check can be carried out manually or in an assisted manner. Thus, the detection system of the machine 1, formed for example by an optical reading device and / or an image capture device and / or a mechanical device, is configured to detect the position of the starting optical system 20, 41 on the receiving support and / or relative to the predetermined position in the reference frame of the machine 1.

[0177] The corrective action may be the manual or automated repositioning of the starting optical system 20, 41 on the receiving support 10 and / or of the receiving support 10 itself in the machine 1.

[0178] The corrective action may be, as a variant or in addition, the modification of the additive manufacturing instruction of the complementary optical element 25, 30, 35, 47 and 50 and / or of the ophthalmic lens 12 to adapt it to the initial position of the starting optical system.

[0179] The method further comprises the step 500 of additively manufacturing the complementary optical element 25, 30, 35, 47 and 50 with the additive manufacturing machine 1 or another additive manufacturing machine such as a stereolithography machine, directly on the starting optical system 20, 41 according to a determined geometry and according to a determined manufacturing instruction.

[0180] The method optionally comprises step 600 of irradiating the obtained ophthalmic lens 12. This step 600 consists of completing the polymerization of the complementary optical element 25, 30, 35, 47 and 50.

[0181] The method optionally comprises the step 700 of at least partially trimming the ophthalmic lens 12. This step 700 consists of creating a peripheral slice on the lens 12 which is adapted to a predetermined frame. This step 700 is only necessary if the starting optical system is not, before step 500, of manufacturing the complementary optical element already with the contour adapted to the predetermined frame.

[0182] The method optionally comprises step 800 of treating / varnishing at least one face of the ophthalmic lens 12. This step 800 consists of adding a coating having predetermined functional properties on at least one of the two faces of the lens 12. This may be, for example, an anti-fog and / or anti-reflective coating and / or a tint and / or a photochromic and / or anti-scratch coating and / or the deposition of a polarized film, etc. It may also be a varnish film chosen to compensate for surface irregularities (smoothing varnish configured to smooth out the roughness and residual surface roughness from additive manufacturing).In particular, reference is made here to layers of varnish such as those presented in the applicant's patent applications EP1896878, or JP 2002-182011 which are configured to allow a surface having a certain initial quality to reach an ophthalmic quality, the application of this layer of varnish not making it possible to modify the main curvatures of the surface of the lens, such as the main curvature or a pattern drawing the addition(s).

[0183] There figure 7 illustrates steps of the manufacturing process and more precisely steps for determining a manufacturing instruction for the complementary optical element 25, 30, 35, 47 and 50, and / or the ophthalmic lens 12, with a view to its additive manufacturing using the additive manufacturing machine 1 illustrated in the figure 1 .

[0184] The control and command unit 2 of the additive manufacturing machine 1 is configured to receive at step 100 a file comprising prescription values ​​of a wearer of the ophthalmic lens 12 to be manufactured.

[0185] These wearer prescription values ​​are generally expressed in diopters (D).

[0186] The unit 2 is further configured to receive at step 101 additional wearing and personalization data, including data relating to binocular vision, this data being linked both to the wearer, to a frame intended to receive the ophthalmic lens 12 and to the prescription.

[0187] It should be noted that these additional wearing and personalization data correspond, for example, to geometric values ​​which characterize in particular the frame and the visual behavior of the wearer. This may be, for example, a distance between the eye and the lens and / or a position of the center of rotation of the eye, and / or an eye-head coefficient, and / or a pantoscopic angle and / or a curve of the frame and / or the outline of the frame.

[0188] The unit 2 is configured to determine in step 102 a corrective optical function adapted to the wearer from the wearer prescription values ​​and the additional wearing and personalization data received in the respective steps 100 and 101, and as a function of the geometric positioning of the lens 12 relative to the wearer's eye.

[0189] This corrective optical function adapted to the wearer corresponds to the optical function, called target, of the ophthalmic lens 12 to be manufactured.

[0190] It should be noted that the determination of the corrective optical function adapted to the wearer can be carried out, for example, using ray tracing software, which makes it possible to determine the wearer power and the resulting astigmatism of the lens under the conditions in which the latter is worn. Optimization can be carried out by following well-known optical optimization methods.

[0191] It will also be noted that step 101 is optional and therefore that the corrective optical function adapted to the wearer can be determined by the unit 2 in step 102, only from the prescription values ​​received in step 101, and as a function of the geometric positioning of the lens 12 relative to the wearer's eye.

[0192] Unit 2 is configured to generate in step 103 a file called “optical function 1” which characterizes this corrective optical function adapted to the wearer, also noted F 1 , determined in step 102.

[0193] It will be noted that the corrective optical function adapted to the wearer can, instead of being determined by the unit 2 in step 102, be directly received by this unit 2 in the form of such a file.

[0194] Unit 2 is configured to receive at step 105 a file comprising characteristics of the basic optical function, denoted F 0 , of the starting optical system 20, 41. This optical function can be simple, complex or afocal (in other words zero).

[0195] This file is substantially similar to the “optical function 1” file except that it does not characterize the ophthalmic lens 12 to be manufactured but the starting optical system 20, 41 chosen.

[0196] It will be observed that this file includes characteristics which are here measured directly on this starting optical system 20, 41, at step 104. These characteristics could be predetermined and known, without requiring measurements.

[0197] Unit 2 is configured to determine, in step 106, a complementary optical function, denoted F 2 , of the complementary optical element 25, 30, 35, 47 and 50 that the latter presents after additive manufacturing.

[0198] IlThis is in fact the complementary optical function to be provided to this complementary optical element 25, 30, 35, 47 and 50, called “optical function 2”, taking into consideration that the latter is manufactured additively directly on the starting optical system 20, 41 (itself having a basic optical function), so that the ophthalmic lens 12, the result of this additive manufacturing of the complementary optical element 25, 30, 35, 47 and 50 directly on the starting optical system 20, 41, provides the wearer with the corrective optical function F 1 which is prescribed for him.

[0199] This determination step 106 is therefore carried out from the characteristics included in the file generated in step 103 and the file received (or generated) in step 105, respectively relating to the corrective optical function adapted to the wearer as well as to the basic optical function of the starting optical system 20, 41.

[0200] Unit 2 is configured to generate in step 107 a file called “optical function 2” which characterizes the complementary optical function of the complementary optical element 25, 30, 35, 47 and 50 determined in step 106.

[0201] Unit 2 is further configured to receive in step 109 a file comprising characteristics of the geometry of the starting optical system 20, 41.

[0202] It will be observed that this file includes geometric characteristics which are here measured directly on this starting optical system 20, 41, at step 108. These characteristics could be predetermined and known, without requiring measurements.

[0203] Among these geometric characteristics can be found in particular the outline of the starting optical system, the coordinates (x, y, z) of a finite number of points of each surface or a surface function for each surface as well as a thickness separating the two surfaces at any point... etc.

[0204] Unit 2 is further configured to receive in step 111 a file comprising characteristics linked to the refractive index of the starting optical system 20, 41.

[0205] It will be noted that the characteristics related to the refractive index of this starting optical system 20, 41 can be measured or predetermined and known, without requiring measurements, whether the index is constant at all points or not in the starting optical system.

[0206] The unit 2 is further configured to receive at step 112 a file comprising characteristics linked to the final refractive index of the material 55, 60 used for the additive manufacturing of the complementary optical element 25, 30, 35, 47 and 50. This index is said to be final because it is the index that this complementary optical element 25, 30, 35, 47 and 50 must have once the latter has been manufactured and polymerized on the starting optical system 20, 41, to form the ophthalmic lens 12.

[0207] The unit 2 is configured to determine, in step 113, geometric characteristics of the complementary optical element 25, 30, 35, 47 and 50 and / or of the ophthalmic lens 12 to be manufactured, from the files generated and / or received in steps 107, 109, 111 and 112, respectively relating to the complementary optical function of the complementary optical element 25, 30, 35, 47 and 50, to the geometry and index of the starting optical system 20, 41 as well as to the value of the final index of the manufacturing material of the complementary optical element 25, 30, 35, 47 and 50.

[0208] The unit 2 is further configured to generate in step 114 a file which characterizes the geometric characteristics of the complementary optical element 25, 30, 35, 47 and 50 and / or of the ophthalmic lens 12 to be manufactured, determined in step 113.

[0209] This file includes geometric characteristics of the complementary optical element 25, 30, 35, 47 and 50 and / or of the ophthalmic lens 12 representative of the desired geometry of this complementary optical element 25, 30, 35, 47 and 50 and / or of this ophthalmic lens 12 once this complementary optical element 25, 30, 35, 47 and 50 has been manufactured additively directly on the starting optical system 20, 41, with its final index (i.e. once polymerized or photo-polymerized).

[0210] It should be noted that this file is a so-called surface file which is provided for example with geometric characteristics in the form of coordinates x, y, z, θ, at a finite number of points, or a surface function z = f(x,y) defining each face, characteristics linked to a refractive index at any point, various distances and angles such as those mentioned above.

[0211] In other words, this surface file reflects a description of the desired geometry of this complementary optical element 25, 30, 35, 47 and 50 and / or of this ophthalmic lens 12 to be manufactured, with in practice, a determined arrangement of the predetermined volume elements of the material(s).

[0212] It will be noted that this surface file can be visualized in the form of 3D modeling data typically in a CAD design file in order to represent the ophthalmic lens 12 provided with its starting optical system 20, 41 and its complementary optical element 25, 30, 35, 47 and 50 as a digital object.

[0213] It will be noted that the geometry of the complementary optical element 25, 30, 35, 47 and 50 is determined so as to be directly adapted to the contour of the frame in which the lens 12 is configured to be mounted. A trimming step is then only necessary if the starting optical system 20, 41 does not itself have a contour adapted to this frame. As a variant, not covered by the invention as claimed, the contour of the element 25, 30, 35, 47 and 50 and / or of the lens 12 defined in this file does not correspond to the contour of the frame and a trimming operation is necessary, whatever the contour of the starting optical system 20, 41.

[0214] Unit 2 is configured to determine, optionally, in step 115, a dimensional shrinkage and / or a variation in index of the complementary optical element 25, 30, 35, 47 and 50. These are possible subsequent developments, on the one hand, of the refractive index of the material 55, 60 in which the complementary optical element 25, 30, 35, 47 and 50 is manufactured and on the other hand, of the geometry (dimensional shrinkage) of this complementary optical element 25, 30, 35, 47 and 50.

[0215] Unit 2 is further configured to determine in step 116 the manufacturing instruction for the complementary optical element 25, 30, 35, 47 and 50, and thus generate a manufacturing file called “manufacturing instruction”.

[0216] This step 116 of determining the instruction is carried out from the characteristics included in the file generated in step 114 relating to the geometry of the complementary optical element 25, 30, 35, 47 and 50 and / or of the ophthalmic lens 12 directly on the starting optical system 20, 41, with final index, and from the determination of the dimensional shrinkage and the variation in index in step 115.

[0217] The unit 2 is configured to generate in step 117 the manufacturing file corresponding to the manufacturing instruction of the complementary optical element 25, 30, 35, 47 and 50 and / or of the ophthalmic lens 12 directly on the starting optical system 20, 41, itself positioned on the receiving support 10 according to a determined position in a reference frame of the additive manufacturing machine 1.

[0218] This “setpoint” file is similar to the geometry file of the complementary optical element 25, 30, 35, 47 and 50 and / or of the ophthalmic lens 12 generated in step 114, except that it reflects a transcribed description of the desired geometry of this complementary optical element 25, 30, 35, 47 and 50 and / or of this ophthalmic lens 12 to be manufactured, with in practice, a modified arrangement of the predetermined volume elements of the material(s); including a determined angular orientation of the complementary optical element 25, 30, 35, 47 and 50 on the starting optical system 20, 41 and / or of the starting optical system 20, 41 on the receiving support 10 and / or of the receiving support 10 in the machine 1, for the manufacture of this complementary optical element 25, 30, 35, 47 and 50;and modifications linked for example to a possible dimensional shrinkage as well as to a possible variation in index of the complementary optical element 25, 30, 35, 47 and 50 determined in step 115.;

[0219] It is also from this “instruction” file which characterizes the geometry and the complementary optical function to be provided to the complementary optical element 25, 30, 35, 47 and 50 that the latter is manufactured additively.

[0220] For this, the unit 2 can also be configured to launch at step 118 the additive manufacturing of the complementary optical element 25, 30, 35, 47 and 50 directly on the starting optical system 20, 41 in the additive manufacturing machine 1, on the basis of the characteristics of the manufacturing file generated at step 117.

[0221] The control and command unit 2 is configured to execute software for implementing different steps of the manufacturing process of the ophthalmic lens 12, using the parameters received, in order to determine the manufacturing instruction for the complementary optical element 25, 30, 35, 47 and 50 and / or the ophthalmic lens 12, or even to produce this complementary optical element 25, 30, 35, 47 and 50 to obtain the ophthalmic lens 12.

[0222] In a variant not illustrated, a client-server communication interface comprises a so-called provider side and another so-called client side, these two sides communicating via a network, for example of the Internet type.

[0223] The supplier side has a server connected to a control and command unit of the same type as that of the figure 1 , but this time not integrated into an additive manufacturing machine, this server being configured to communicate with the internet interface.

[0224] The client side is configured to communicate with the internet interface, and is connected to a control and command unit of the same type as that on the supplier side.

[0225] In addition, the customer-side unit is connected to an additive manufacturing machine of the same type as the one on the figure 1 to manufacture the complementary optical element of the ophthalmic lens.

[0226] The unit is configured to receive, on the client side, the data files corresponding to steps 100, optionally 101, 105, 109, 111 and 112.

[0227] This unit sends this data via the internet interface and the server to the unit on the supplier side for determining the manufacturing instructions for the complementary optical element and / or the ophthalmic lens.

[0228] This unit executes via its data processing system the computer program it contains to implement the manufacturing process and thus deduce the manufacturing instruction for manufacturing the complementary optical element and / or the ophthalmic lens.

[0229] The unit sends, via the server and the network, a file representing the determined manufacturing instruction to the control and command unit on the client side.

[0230] This client-side unit is configured to execute software for implementing the ophthalmic lens manufacturing process, using the received parameters, in order to produce the complementary optical element to obtain the ophthalmic lens.

[0231] In a variant not illustrated, the method may comprise different steps relating to the optimization of additive manufacturing and in particular to the deposition of at least one material on the starting optical system to manufacture the complementary optical element.

[0232] The method may comprise, for example either during the execution of the instruction file or during the establishment of said file, a step of determining a preferential orientation of the starting optical system in the additive manufacturing machine according to at least one criterion.

[0233] For example, in the case of an additive manufacturing machine comprising scanning by a series of nozzles, a scanning direction of the series of nozzles can be identified so as to minimize, for the entire additive manufacturing step of the complementary optical element, a distribution of distances between each nozzle of the series of nozzles and the surface of the starting optical system. Indeed, when the surface of the starting optical system is pseudo-spherical, and a series of nozzles is positioned above the surface, it is possible, taking into account the altitude profile of each of the nozzles of the series of nozzles, to define a value expressing the variations in distance between each nozzle and a point of the target surface for this nozzle. This value can be a standard deviation, an average, a difference between a maximum distance and a minimum distance or any other parameter.

[0234] It will be noted that by taking into account the radii of curvature defining the surface of the starting optical system and the contour of the complementary optical element to be deposited on the surface, it is possible to find an orientation of the series of nozzles relative to the starting optical system which, for each position of the series of nozzles during the additive manufacturing step, minimizes the value expressed above so as to minimize the variations in distance between the nozzle and the starting optical element.

[0235] For example, if the complementary optical element to be manufactured includes one dimension larger than another, it is common for the height variation to be greater along the path along the larger dimension. An inverse situation may occur for certain toric, a-toric, aspheric and / or addition lenses, depending on the orientation of the torus axes and / or the positioning of the addition.

[0236] The more uniform the distance between the surface to be covered and each nozzle is for the entire series of nozzles, the easier it is to control the deposition precision when projecting material through the nozzles.

[0237] Alternatively, if the series of nozzles has a given length and there is a rectangle containing the contour of the complementary optical element and tangent to this contour at at least one point on each of the sides of this rectangle, the length of the smallest of the sides of which is less than the length of the series of nozzles, the starting optical system can be positioned so that the entire contour of the complementary optical element is covered by the series of nozzles in a single pass.

[0238] It will be noted that the steps relating to the optimization of additive manufacturing, described above, can be implemented both in a method for manufacturing an ophthalmic lens such as that described above, that is to say comprising a step of additive manufacturing of a complementary optical element on a starting optical system, and in other methods for manufacturing an ophthalmic lens, for example comprising a step of additive manufacturing of the ophthalmic lens (in one piece), or a step of additive manufacturing of a complementary optical element on a manufacturing support of the additive manufacturing machine followed by a step of transferring this complementary optical element (or even this element together with the manufacturing support) to a starting optical system having an optical function.

[0239] In variants not shown: the plurality of predetermined volume elements juxtaposed and superimposed form superimposed layers which each have a constant or variable thickness along the length and / or which all have the same thickness or not; the material is a photopolymerizable composition comprising one or more families of molecules having one or more acrylic, methacrylic, acrylate, methacrylate functions, a family of molecules having one or more epoxy, thioepoxy, thiol-ene functions, a family of molecules having one or more vinyl ether, vinyl caprolactam, vinylpyrolidone functions, a family of hyperbranched type material, of organic / inorganic hybrid type, or a combination of these functions; the chemical functions mentioned can be carried by monomers or oligomers or a combination of monomers and oligomers; the material can comprise at least one photoinitiator;the material may comprise colloids, in particular colloidal particles having dimensions for example smaller than visible wavelengths, such as for example colloidal particles of silica oxide SiO2 or colloidal particles of zirconia oxide ZrO2; the material may comprise, in at least some of the predetermined volume elements, a pigment or a dye, for example a dye which belongs to the families of azo, or rhodamines, or cyanines, or polymethines, or merocyanines, or fluoresceins, or pyrylium, or phthalocyanines, or perylenes, or benzanthrones, or anthrapyrimidines, or anthrapyridones, or a dye provided with metal complexes such as rare earth chelates or cryptates;the starting optical system is made of other materials such as polycarbonate, polymethyl(meth)acylate, polyamide or thiourethane, allyl-carbonate, acrylic, urethane and / or episulfide polymers, these materials being well known to those skilled in the art in the field of ophthalmic lenses; the starting optical system may comprise on at least one face one or more treatments among an anti-reflection treatment, an anti-fouling treatment, an anti-scratch treatment, an anti-shock treatment, a polarized filter; the starting optical system may comprise one or more treatments such as those mentioned above on both surfaces, or the starting optical system may comprise a bonding layer and / or may comprise at least one layer making it possible to carry out an optical impedance adaptation between the starting optical system and the complementary optical element when these have different refractive indices;the treatments mentioned above can for example be carried out by transfer or by lamination, in other words by bonding, of a functional film; the starting optical system can comprise an active element such as a waveguide or a network of cells comprising one or more materials having a variable index or absorption depending on an external stimuli such as an electrochromic composition or liquid crystals or a photochromic composition; when the starting optical system comprises ophthalmic lenses already mounted in a frame, the method can comprise a step of dismantling the ophthalmic lenses before positioning them in the additive manufacturing machine; the method further comprises one or more other manufacturing steps, for example a trimming step and / or a marking step to form so-called temporary marks;the additive manufacturing process comprises an additional step of thermal irradiation to polymerize or harden the entire additively manufactured structure; the manufacturing process comprises a step where the variation in index of the material of the complementary optical element can be taken into account in the form of an iterative optimization loop according to known optimization procedures; the material of the complementary optical element optionally comprises one or more dyes, and / or nanoparticles configured to modify its optical transmission and / or its appearance, and / or nanoparticles or additives configured to modify its mechanical properties; the additive manufacturing machine is not a three-dimensional printing machine but rather a stereolithography machine (SLA for “Stereolithography; Apparatus » in English) or a thermoplastic wire extrusion machine, also called a stretched wire deposition model (FDM for " Fused Deposition Modeling» in English); at least one control and command unit comprises a microcontroller in place of the microprocessor; the client-server communication interface comprises devices configured to transfer the manufacturing instruction of the complementary optical element and / or the ophthalmic lens determined by a computer program, which comprises instructions configured to implement each of the steps of the manufacturing method described above when this computer program is executed in at least one control and command unit which comprises systemic elements configured to execute said computer program; the communication interface allows communication via means other than the internet network, for example via an intranet network or a secure private network;and / or the communication interface allows the entire computer program to be transferred to a remote data processing system for implementing the manufacturing process in another manufacturing system provided with an additive manufacturing machine and optionally at least one trimming machine and / or one or more other processing machines.;

[0240] It is recalled more generally that the invention is not limited to the examples described and represented. The invention as claimed is defined in the set of claims below.

Claims

1. Process for manufacturing at least one ophthalmic lens (12) having at least one optical function, characterized in that it comprises: - the step (200) of providing a starting optical system (20; 41) of said at least one ophthalmic lens (12), said starting optical system (20; 41) having been manufactured with an outline adapted to a shape of a predetermined frame and having a base optical function delivered by a front face (23; 46) and a back face (22; 45) of said starting optical system (20; 41); and - the step (500) of additively manufacturing an optical element (25; 30, 35; 47; 50) which is complementary to said at least one ophthalmic lens (12), by depositing a plurality of predetermined volume elements of at least one material having a predetermined refractive index, directly on at least one of said front face (23; 46) and back face (22; 45) of said starting optical system (20; 41); with said additive manufacturing step (500) which comprises the step (116) of determining manufacturing settings for said complementary optical element (25; 30, 35; 47; 50) from characteristics of said at least one optical function to be provided to said at least one ophthalmic lens (12), from characteristics of said at least one base optical function of said starting optical system (20; 41), from geometric characteristics of said starting optical system (20; 41) and from said predetermined refractive index of said at least one material; and with the complementary optical element (25, 30, 35, 47 and 50) which has a geometry which is determined so as to be directly adapted to the outline of the frame in which the ophthalmic lens (12) is configured to be fitted.

2. Process according to Claim 1, characterized in that said additive manufacturing step (500) comprises the step (113) of determining geometric characteristics of said complementary optical element (25; 30, 35; 47; 50) and / or of said at least one ophthalmic lens (12) from characteristics of at least one complementary optical function to be provided to said complementary optical element (25; 30, 35; 47; 50), from said geometric characteristics of said starting optical system (20; 41) and from said predetermined refractive index of said at least one material.

3. Process according to one of Claims 1 and 2, characterized in that said additive manufacturing step (500) comprises the step (106) of determining at least one complementary optical function to be provided to said complementary optical element (25; 30, 35; 47; 50) from said characteristics of said at least one optical function to be provided to said at least one ophthalmic lens (12) and from said characteristics of said at least one base optical function of said starting optical system (20; 41).

4. Process according to any one of Claims 1 to 3, characterized in that said additive manufacturing step (500) comprises the step (102) of determining said at least one optical function to be delivered to said at least one ophthalmic lens (12) from prescription values associated with a wearer of said at least one ophthalmic lens (12) and from complementary fitting data of said predetermined frame and / or shape data of said frame.

5. Process according to Claim 4, characterized in that said at least one optical function to be delivered to said at least one ophthalmic lens (12) is furthermore determined from complementary fitting data of said predetermined frame and / or personalization data, which correspond to geometric values which characterize the frame and the visual behaviour of the wearer, including a distance between the eye and the ophthalmic lens and / or a position of the centre of rotation of the eye and / or an eye-head coefficient and / or a pantoscopic angle and / or a curve of the frame and / or an outline of the frame.

6. Process according to any one of Claims 1 to 5, characterized in that said additive manufacturing step (500) comprises the step (104) of measuring said characteristics of said at least one base optical function of said starting optical system (20; 41) and / or the step (108) of measuring said geometric characteristics of said starting optical system (20; 41).

7. Process according to any one of Claims 1 to 6, characterized in that said at least one material from which said complementary optical element (25; 30, 35; 47; 50) is additively manufactured is different from the constituent material of said starting optical system (20; 41).

8. Process according to any one of Claims 1 to 7, characterized in that said starting optical system is formed by an assembly (40) comprising said frame (42, 43) and two initial ophthalmic lenses (41) fitted in said frame (42, 43), and said process comprises a step of additively manufacturing two said complementary optical elements (25; 30, 35; 47; 50), one on each of said initial ophthalmic lenses used as starting optical system (41), in order to form two said ophthalmic lenses, with said manufacturing settings which are furthermore determined from characteristics related to the binocular vision of a wearer of said two ophthalmic lenses.

9. Process according to any one of Claims 1 to 8, characterized in that said additive manufacturing step (500) is carried out by depositing a plurality of at least one predetermined volume element of said at least one material on at least all the work area of at least one of said front face (23; 46) and back face (22; 45) of said starting optical system (20; 41).

10. Process according to any one of Claims 1 to 9, characterized in that it comprises, before said additive manufacturing step (500), the step (300) of placing and positioning said starting optical system (20; 41) on a receiving holder (10) in an additive manufacturing machine (1).

11. Process according to Claim 10, characterized in that it comprises, after said step (300) of positioning said starting optical system (20; 41) and before said additive manufacturing step (500), the step (400) of checking the position of said starting optical system (20; 41) in said additive manufacturing machine (1) and the step of triggering a corrective action if there is a discrepancy between the actual position of said starting optical system (20; 41) and a predetermined position.

12. Process according to any one of Claims 1 to 11, characterized in that, after said additive manufacturing step (500), said complementary optical element (25; 30, 35; 47; 50) has an outline substantially equal to that of said starting optical system (20; 41) and configured to be inserted into said predetermined frame.

13. Process according to any one of Claims 1 to 12, characterized in that said starting optical system (41) corresponds to a lens referred to as a demonstration lens fitted in said predetermined frame referred to as a demonstration frame, and said base optical function is zero.

14. Additive manufacturing machine configured to manufacture an ophthalmic lens (12) and comprising a command / control unit (2) provided with system elements (3, 4, 5) configured to run a computer program comprising instructions configured to implement each of the steps of the process according to any one of Claims 1 to 13.

15. Machine according to Claim 14, characterized in that it comprises a receiving holder (10) configured to receive said starting optical system (20; 41), with said receiving holder (10) and / or said starting optical system (20; 41) which are configured so that the latter is positioned in a predetermined position relative to a coordinate system of said machine (1) and / or a detecting system, for example formed by an optical reading device and / or an image-capturing device, configured to detect the position of said starting optical system (20; 41) on said receiving holder (10) and / or relative to said predetermined position in said coordinate system of said machine (1).