Method of manufacturing a contact lens

Abstract

The invention relates to a method for producing an individually adapted contact lens and a contact lens produced according to the method. The invention also relates to a corresponding method for producing universally usable contact lenses by a molding method and a method for producing a mold used in this method. According to the invention, a contact lens blank having a back side and a front side is provided, and topography data describing an inverse representation of the three-dimensional topography of the user's eye. A wearing zone arranged on the back side surface of the contact lens is shaped on the basis of the topography data, and an additional three-dimensional surface structure is formed on the wearing zone. In this way, when the contact lens is worn, the wearing zone rests on the user's eye in the form of a surface defined by the inverse representation of the three-dimensional topography of the eye superimposed with the three-dimensional surface structure.

Description

Technical Background

[0001] This invention generally relates to a method for manufacturing an individually fitting contact lens and the contact lens manufactured by this method. Furthermore, this invention relates to a corresponding method for manufacturing a universally usable contact lens by molding, or a method for manufacturing a mold used in this method.

[0002] According to the present invention, in this case, both the visual correction of the eye with aberrations achieved by the contact lens and the detailed morphology of the cornea are taken into consideration, while ensuring daily comfort and tolerability.

[0003] The optical effects of contact lenses are particularly limited by the corresponding eye defect and / or the intended use of the contact lens, such as progressive vision contact lenses or multifocal lenses, in which different refractive power regions are imaged. In this case, influencing factors can also be the specific morphology of the lens, the specific morphology / physiology of the cornea, and the specific geometry of the eyeball. In this respect, the specific geometry of the eyeball can also be affected by orthokeratology lenses to correct defective vision. These are shape-stable, highly oxygen-permeable lenses specifically designed to reshape the cornea overnight.

[0004] The optical effects of a contact lens can be achieved by appropriately selecting the front geometry, the rear geometry, or a combination of both. The correspondingly defined optical zone is mostly but not exclusively arranged around the geometric center of the lens, but this zone only forms a sub-region of the entire contact lens.

[0005] Other sub-regions of the contact lens, typically arranged in a ring around the optically active area at least in segments, have different functions, such as positioning the lens on the eye (rotation, basic position, etc.), providing orientation or positioning assistance (prism / thinning (slab off), weighting, alignment edge, etc.), ensuring sufficient support area (hereinafter also referred to as "landing area"), or "bypassing" particularly sensitive areas of the eye (high nerve density areas (limbus area), scars, etc.).

[0006] Although the support area typically has no optical effect, it is extremely relevant to the use of the lens because it represents the area where the lens rests directly on the eye. Therefore, a poorly designed support area can lead to serious damage, such as loss of the desired position of the contact lens on the eye and a corresponding reduction in corrective effect, interaction with the eyelids that may cause the lens to shift unintentionally, eye irritation caused by, for example, "pressure points," or inhibition of the tear film on the ocular surface and thus impaired oxygen supply to the eye.

[0007] In current methods for manufacturing contact lenses, the support area is basically achieved by three geometric variants: a spherical basic shape, a torus basic shape, or a quadrant-symmetric "Quadsim" shape, where the geometry is typically defined by four meridians spaced 90° apart.

[0008] The final shape used for the patient / wearer is determined by the appropriate optometrist / optician. The spherical basic shape is typically used for eyes with a high degree of rotational symmetry, while the toroidal or quadrant-symmetrical basic shapes are used for eyes with a sufficiently large deviation from rotational symmetry (e.g., in the case of corneal curvature).

[0009] The eye measurements required for lens fitting can be performed using different methods in this case. According to current methods, qualitative measurements of lens support on the eye are performed, for example, using fluorescence imaging and a test lens. In this case, the fluorescence image shows the placement of the test lens, and the optometrist assesses the fit and iteratively refines the lens design. The actual morphology / geometry of the user's eye can be determined through quantitative measurements of the three-dimensional eye morphology, thereby significantly reducing the number of iterations.

[0010] In this quantitative measurement context, torus compensation is partly provided by the accompanying software.

[0011] In addition to the basic shape of the support area, the latter is essentially defined by its (radial) starting and ending points—hereinafter also referred to as the starting / ending diameter—and its edge shape, which is specified by conventional parameters such as bevel radius, edge uplift, non-rotationally symmetric edges, etc.

[0012] Therefore, in the currently used methods, the support zone is defined by selecting its basic shape (spherical, torus, etc.), start and end diameters, and edge shape. In this case, it should be taken into account that the support zone typically does not form a perfect inverse of the actual shape of a given eye. Instead, a “gap” or distance exists between the contact lens and the eye, at least in some areas, which is bridged by the tear film located on the surface of the eye.

[0013] The tear film performs two tasks in this situation. On the one hand, it avoids optical aberrations. Because the tear film itself has optical effects due to its refractive index, it can avoid or compensate for optical aberrations caused by the lens "lifting" away from the cornea. On the other hand, the tear film allows for the exchange of the liquid film under the lens, so as to allow for a good oxygen supply to the surface of the eye on the one hand, and remove any debris / cells that may be generated on the other.

[0014] In general, it should be noted that the better the support area of ​​the lens is formed, the better the wearing comfort, local positioning, oxygen supply, and removal of abrasive / cell debris. Summary of the Invention

[0015] Therefore, the object of the present invention is to optimize the support area of ​​the lens to the greatest extent possible in respect of the above-mentioned points.

[0016] According to the present invention, the support region is therefore constructed in a different manner. In particular, the present invention aims to optimize the support region by superimposition of different surfaces.

[0017] By using measuring instruments for measuring the geometry of a three-dimensional eye, the actual morphology of the user's eye can first be measured, at least in those areas intended to serve as support zones. An "ideally fit" support zone can be defined by forming a surface with an inverse shape. This inverse shape can be formed by creating a corresponding point cloud and by mathematically describing both, for example, using methods commonly used in this context (B-spline NURBS, Zernike polynomials, etc.). However, it should be considered that a "perfect inverse shape" could lead to negative properties, as the lens might adhere to the eye, resulting in an uncomfortable wearing experience. Tear film flow may also stagnate in this case, preventing tear exchange, which adversely affects oxygen supply or cell / debris removal. To prevent this, according to the invention, a three-dimensional surface structure is added to the "perfect inverse shape." In this case, the three-dimensional surface structure may be selected from a corresponding library of existing and predefined morphologies and mathematically integrated with the "perfect inverse shape," for example, by overlay.

[0018] As a result of the three-dimensional surface structure, the lens in the support area is made to fit the actual shape of the user's eye as best as possible, but there is no planar placement of the lens in the entire support area.

[0019] Therefore, one advantage of the method according to the invention is that a significantly wider support zone can be provided by using an additional three-dimensional surface structure combined with a perfectly inverted surface. This avoids, on the one hand, the negative effects of lens adhesion to the eye and associated poor wearing comfort that are commonly present today, and on the other hand, the negative effects of reduced tear exchange and consequently insufficient oxygen supply to the eye region located below the lens when the support zone is completely planar. The wider support zone also significantly improves and stabilizes the lens positioning on the eye.

[0020] Even though the method according to the invention can first be used in conjunction with individually adapted contact lenses, it can be readily transferred to the manufacture of universally available contact lenses. In this sense, for the molding method used in this case, the mold will be designed accordingly (i.e., at least in the area of ​​the support region of the contact lens to be molded), and a "reverse" three-dimensional surface structure will be applied to the given surface in the mold, so that the contact lens molded with this mold will again have the corresponding desired three-dimensional surface structure in the support region.

[0021] Therefore, according to a first aspect, the present invention relates to a method for forming a support area for a contact lens adapted to an individual user, wherein the support area of ​​the contact lens is the region where the contact lens rests on the user's eye when the contact lens is worn. The method first includes providing a contact lens blank having a rear side and a front side, the rear side facing the user's eye when the contact lens is worn, and the front side facing away from the eye when the contact lens is worn. Furthermore, topographic data is provided, which substantially represents an inverse image of the three-dimensional topography of the user's eye, at least in the area covered by the support area of ​​the contact lens when the contact lens is worn. Based on this topographic data, a support area is formed disposed on the rear surface of the contact lens. Furthermore, an additional three-dimensional surface structure is formed on the support area of ​​the contact lens such that, when the contact lens is worn, the support area of ​​the contact lens rests on the user's eye in the form of a surface defined by an inverse image of the three-dimensional topography of the eye superimposed with the three-dimensional surface structure.

[0022] In this context, the topographic data used in the present invention can be determined by measuring the contact lens user in a well-known manner. Of course, in this case, the topographic data can capture not only the area covered by the support area of ​​the lens when the contact lens is worn, but also the remaining area covered by the contact lens, i.e., the area including the optically active area of ​​the contact lens. In this case, the topographic data can then also be used to define the optical zone to be formed accordingly for correcting visual impairment, since the actual shape of the user's eye can also play a relevant role here.

[0023] According to a preferred embodiment of the invention, the formation of the support region and / or the formation of the three-dimensional surface structure can be achieved by material removal processing following a substantially helical path. In this case, multiple separate processing steps can be performed using different tools in the sense of roughing / finishing.

[0024] Preferably, before forming the support region, the method further includes providing data on the three-dimensional surface structure and generating a fused dataset by overlaying the topographic data with the three-dimensional surface structure data. In this case, the support region is then formed based on the fused dataset. In this way, the formation of the support region disposed on the rear surface of the contact lens can be based on the topographic data, and the formation of the additional three-dimensional surface structure on the support region of the contact lens can be carried out in a common processing step.

[0025] In this embodiment, the generation of the fused dataset may include a spatial overlay of topographic data and three-dimensional surface structure data. This can be done in a known manner within the context of corresponding mathematical overlay and dataset processing.

[0026] When using a fused dataset, the formation of the support zone can also preferably be achieved through material removal processing that essentially follows a spiral path. Here, again, multiple separate processing steps can be performed using different tools in the sense of roughing / finishing. In this case, the proportion of the 3D surface structure data in the fused dataset can be mapped by the movement variations of the processing tools with respect to their engagement angle and / or engagement depth.

[0027] As an alternative to combining the fused dataset with the formation of a support region, including a three-dimensional surface structure, in a single working step, the formation of the support region arranged on the rear surface of the contact lens based on topographic data, and the formation of the additional three-dimensional surface structure on the support region of the contact lens, can also be performed in two separate working steps. In this case, the two formation steps can be performed using the same processing method, such as a material removal process. However, it is also conceivable that the two formation steps can be performed using different processing methods. Thus, for example, in the first step, the support region can first be formed based on the topographic data using a material removal process. Then, in the second step, the additional three-dimensional surface structure can be introduced into the support region by means of surface processing performed by a laser.

[0028] According to another aspect, the present invention also relates to a method for producing a contact lens, wherein a contact lens blank having a rear side and a front side is provided, the rear side facing the user's eye when the contact lens is worn, and the front side facing away from the eye when the contact lens is worn. Based on provided optical data representing the aberrations of the user's eye to be corrected by the contact lens, an optically active area is formed on the front side of the contact lens and / or on the rear side of the contact lens. Furthermore, a contact lens support area having a corresponding three-dimensional surface structure is formed according to one of the above methods.

[0029] The formation of the optical active area and the support area on the rear side of the contact lens is preferably carried out in one processing step.

[0030] In this case, the formation of both the optically active region and the support region is preferably carried out by a material removal process following a spiral path.

[0031] The present invention also relates to a contact lens adapted to an individual user, the contact lens having a support area formed by one of the above methods and having a corresponding three-dimensional surface structure.

[0032] According to another aspect, the present invention also relates to a method for generating a mold for manufacturing a contact lens using a molding method. According to the invention, the method includes forming a portion of the mold corresponding to a support area disposed on the rear surface of the contact lens to be manufactured, facing the user's eye. In this case, the support area of ​​the contact lens to be manufactured is the area where the contact lens rests on the user's eye when worn. In this case, the forming is performed using a fusion dataset generated by overlaying topographic data with data of a three-dimensional surface structure, the topographic data representing an inverse image of the three-dimensional topography of the user's eye, at least in the area covered by the support area of ​​the contact lens when worn.

[0033] In this way, it is possible to achieve, even in the case of commonly available contact lenses manufactured by molding methods, that the support area has the advantages of the invention in terms of wearing comfort and tear exchange.

[0034] In all the methods described above according to the invention, it should be considered that the formation of the support area should be carried out in a manner that takes into account the economics of manufacturing. In this sense, especially when considering morphological data, it may be necessary to make a trade-off between the working time / complexity required to process the contact lens blank and the final achievable wearing comfort, since even if it were possible to obtain an image that is exactly the same as the user's eye morphology, it would only be possible with a significant increase in manufacturing expenditure. In this case, it is sufficient for the invention to approximately adapt the support area to the actual three-dimensional morphology of the user's eye, which can typically be done by predefining different reference points of the morphology during blank processing, which are then further processed mathematically and used as the basis for machining.

[0035] According to the present invention, the three-dimensional surface structure to be applied to the support area preferably has an amplitude in the range of 0.01-0.5 mm, more preferably in the range of 0.05-0.3 mm, when viewed from the rear side to the front side of the contact lens. In other words, there is a corresponding distance between the "highest point" and the "lowest point" of the three-dimensional surface structure. Therefore, with the conventional tear film thickness in the range of 0.005 mm-0.01 mm, the three-dimensional surface structure can ensure a certain storage function while ensuring sufficient tear exchange. It should be noted here that the three-dimensional surface structure does not need to have a constant amplitude on the support area or even only in some of its regions. It can vary between a predefined maximum and minimum value. The three-dimensional surface structure can also have a partial amplitude of 0, i.e., it can be flat.

[0036] In a preferred embodiment, the three-dimensional surface structure can be formed such that the support surface resting on the user's eye in the support area accounts for at most 70%, preferably at most 50%, and particularly preferably at most 30% of the total area of ​​the support area. By limiting the area of ​​the effective support surface accordingly, wearing comfort and lens removability from the eye can be increased, while ensuring sufficient tear exchange.

[0037] The three-dimensional surface structure, viewed in the circumferential direction of the contact mirror, preferably exhibits a periodicity of approximately 2π / n, where n is a natural number. In other words, the three-dimensional surface structure is periodically repeating in the circumferential direction, meaning that the same structure is found again at intervals of 360° / n in the circumferential direction. The use of a three-dimensional surface structure with corresponding periodicity is particularly advantageous in the case of rotational manufacturing methods.

[0038] Furthermore, the three-dimensional surface structure can preferably correspond substantially to a random distribution. This means that the structure does not have a clearly identifiable periodicity in space, but rather corresponds substantially to random noise, wherein, in particular, the amplitude of the three-dimensional surface structure does not correspond to a regular, predefined distribution. The corresponding random distribution need not be generated for each individual support area to be manufactured; rather, it can be based on a pre-generated and stored random distribution. In addition, the term "random distribution" is also intended to cover "artificially generated" or "quasi-random distribution" in the context of this invention.

[0039] The three-dimensional surface structure can preferably correspond to at least a single-level continuous, preferably a triple-level continuous, three-dimensional function on the support region. In this case, a multi-level continuous function is understood as a function whose corresponding derivative is also a continuous function. In this sense, for example, a triple-level continuous function is understood as a function whose first and second derivatives also form a continuous function. In some preferred embodiments, the three-dimensional surface structure can be twice or even three times continuously differentiable.

[0040] In a further embodiment, the three-dimensional surface structure can be formed in such a way that, at least in the circumferential direction, it substantially corresponds to at least one, preferably three, continuous function. In the radial direction, the three-dimensional surface structure should preferably correspond to at least one, one, continuous function.

[0041] The aforementioned (multiple) continuity of the three-dimensional surface structure prevents the formation of edges or other discontinuous transitions between the various structures of the three-dimensional surface structure, which could negatively impact the daily comfort and durability of the contact lens. This continuity also primarily allows for the economical manufacturing of the contact lens, or even material removal processing.

[0042] In principle, and preferably preferably with respect to the entire shape of the support area after formation (i.e., based on both morphological data and three-dimensional surface structure), continuity should be provided to ensure the desired wearing comfort. C2 continuity should preferably be provided in the final result on the support area.

[0043] However, here, particularly the transitions between sub-regions (e.g., radially), may be discontinuous in the original definition / calculation of the surface. Since it is impossible to operate discontinuously during material removal processing, the surface must be modified in such processing methods to force continuity from this discontinuity. In this sense, at least in the transition regions of sub-regions, the desired C2 continuity is not always necessarily achievable.

[0044] In a further embodiment, the three-dimensional surface structure may include at least one annular surface modulated circumferentially by a sine function. By appropriately selecting the sine frequency (periodity) and amplitude, the corresponding effective support surface of the support region can be set in a simple manner as needed. In this case, the three-dimensional surface structure may also have multiple annular surfaces with different sine modulations in terms of periodicity and / or amplitude.

[0045] In various embodiments, the three-dimensional surface structure may also comprise a plurality of concentric annular surfaces, which are preferably separated from each other by annular grooves. The three-dimensional surface structure may be formed differently on each annular surface. If the annular surfaces are separated from each other by corresponding annular grooves, they may preferably have dimensions significantly larger than the depth and width of the surface structure given in the annular surface. This advantageously allows for further improvement of tear exchange in the support region.

[0046] In one embodiment, viewed from the center of the lens, the three-dimensional surface structure may correspond to a superposition of a first sine function along the radial direction and a second sine function along the circumferential direction. In this case, the periodicity and amplitude of the two sine functions may be different.

[0047] The three-dimensional surface structure can preferably be selected from a library of predefined surface structures based on morphological data. This has the advantage that the three-dimensional surface structure does not need to be recalculated / generated for each individual manufacturing operation. In this case, individual three-dimensional surface structures particularly suitable for a specific eye type or eye morphology can also be predefined. For example, it is conceivable to classify the various basic shapes of the eye morphology into different groups, and then assign specific three-dimensional surface structures or multiple different three-dimensional surface structures to each of these groups. Example

[0048] The present invention will be explained in more detail below with reference to various embodiments and the accompanying drawings. In the drawings:

[0049] Figure 1 A schematic cross-sectional view depicting the basic structure of the contact mirror is shown;

[0050] Figure 2 Show Figure 1 The diagram depicts a plan view of the rear side of a contact mirror, which is a schematic depiction of various embodiments of the surface structure according to the invention on the support area;

[0051] Figure 3 A schematic illustration of a manufacturing method used in a preferred embodiment of the invention is shown, which is carried out by material removal processing following a substantially spiral path;

[0052] Figure 4a -c indicates that Figure 3 An exemplary unfolded diagram of a spiral traversed by a machining tool in a manufacturing method depicted herein, which has various stacked structures;

[0053] Figure 5a A block diagram illustrating the method according to the present invention is shown;

[0054] Figure 5b A block diagram illustrating a preferred embodiment of the method according to the present invention; and

[0055] Figure 6 A schematic depiction of a molding method for producing a contact lens using a mold constructed according to the invention is shown, having schematic depictions of various embodiments of the surface structure according to the invention on the contact lens support area produced by the method. Attached Figure Description

[0056] Figure 1A schematic cross-sectional view of a conventional contact lens 10 is shown, which in this example is formed substantially rotationally symmetrically about its center 13. The contact lens 10 has a front side 11 and a rear side 12. The rear side 12 faces the user's eye when the contact lens 10 is worn. At its center point 13, the lens 10 has a center thickness, clt. On the front side 11 of the lens 10, a front optical active area 14 with a diameter df is formed, while on the rear side 12 of the lens 10, a rear optical active area 15 with a diameter db is formed. The two optical active areas 14 and 15 work together to correct aberrations in the user's eye. In the depicted example, the diameter df of the front optical active area 14 is larger than the diameter db of the rear optical active area 15.

[0057] Concentrically with the rear optical active region 15, the transition region 16 is adjacent to the rear side 12 of the contact lens 10 in a ring manner, and the support region 17 is adjacent to the transition region 16 in a ring manner.

[0058] In the support area 17, the contact lens 10 rests on the user's eye when worn. To adapt the contact lens 10 to the geometry of the eye at its periphery, the shape of the lens in this area deviates from the central radius defined by the rear optical area 15 by a so-called "edge lift" (el). Furthermore, in its edge region, the lens 10 has a thickness, namely the edge lens thickness (elt), which may differ from the thickness in the central region, namely the central lens thickness (clt).

[0059] Figure 2 Show Figure 1 The schematic rear view of the lens 10 depicted in the figure shows a rear optical region 15, a transition region 16 adjacent to it in a ring shape, and a support region 17.

[0060] According to the present invention, a three-dimensional surface structure has been formed in the support region 17, wherein in Figure 2 Various embodiments of the three-dimensional surface structures 17a-17e are illustrated in the illustration.

[0061] As mentioned above, the three-dimensional surface structure formed in the support area 17 is used to prevent the lens 10 from resting on the user's eye on the entire surface of the support area 17, which has been formed according to the shape data of the user's eye, and to achieve sufficient tear exchange.

[0062] The three-dimensional surface structure 17a shows a completely irregular structure, which can be generated, for example, by mapping random noise.

[0063] The three-dimensional surface structure 17b shows a regular structure based on a two-dimensional superposition of sine functions.

[0064] Three-dimensional surface structure 17b also shows a regular structure based on a two-dimensional superposition of sine functions, which is achieved through the function sin(x) 2 +y 2 ) Detailed limitations.

[0065] The three-dimensional surface structure 17d shows a structure in which irregular wavy channels have been introduced into the surface of the support region 17 of the lens 10.

[0066] The three-dimensional surface structure 17e shows a structure in which regular linear channels have been introduced into the surface of the support region 17 of the lens 10.

[0067] By arranging the channels in the three-dimensional surface structures 17d and 17e in a substantially radial manner, tear exchange between the transition region 16 or optical region 15 and the area of ​​the user's eye not covered by the contact lens 10 can be further improved.

[0068] Figure 2 The three-dimensional surface structures 17a-17e depicted are, of course, merely examples, and in principle, any three-dimensional surface structure can be used according to the invention, which on the one hand can be produced using the selected manufacturing method for the support region 17 or the contact mirror 10, and on the other hand achieves the effects desired according to the invention.

[0069] Figure 3 An overview depiction of a preferred embodiment of the method according to the invention is shown schematically, wherein the rear side 14 of the contact lens 10 is formed by material removal processing using a machining tool. In this case, the lens blank is clamped, and the machining tool follows a substantially helical path 30 during processing. Figure 3 A schematic enlarged depiction 31 of the spiral path 30 is also shown.

[0070] In this case, it should be noted that Figure 3 The path 30 depicted does not necessarily extend over the entire rear side 14 of the lens 10. Rather, it is conceivable that, for example, only the support region 17 is formed by material removal processing. The material removal processing of the rear optical region 15 and / or the transition region 16 and / or the support region can also be performed in multiple separate steps, thus avoiding the creation of a continuous spiral path 30.

[0071] In addition, it should be noted that the track gauge width of path 30, i.e., the radial distance between two consecutive paths, can be less than the effective radius of the machining tool, so that when path 30 is traversed, the same point on the rear side 14 of the contact mirror is engaged multiple times by the machining tool.

[0072] As described above, in a preferred embodiment of the method according to the invention, a fusion dataset is used, which is generated by overlaying the topographic data of the user's eye with the data of the desired three-dimensional surface structure, wherein the support region according to the invention is then formed based on the fusion dataset.

[0073] exist Figure 3 In the material removal process illustrated in the diagram, the machining tool can then be guided on the engagement depth or engagement angle of the machining tool during the traversal path 30, so that the proportion of the three-dimensional surface structure data in the fused dataset is mapped by the movement of the machining tool with respect to its engagement angle and / or engagement depth.

[0074] Figures 4a-4c Examples are provided to depict various shapes that may be achieved by simply superimposing topographic data with data of various three-dimensional structures to be realized.

[0075] In this case, Figures 4a-4c Each of them depicts Figure 3 The spiral path depicted in the figure unfolds at 720°. For simplicity, in the example depicted, it is assumed that the basic paths 40a, 40b, and 40c of the machining tool generated from the topographic data each correspond to a sine function.

[0076] exist Figure 4a In this process, the basic path 40a is superimposed on another sine function 41a with a significantly smaller amplitude and a shorter period, thus obtaining the superimposed function 42a.

[0077] exist Figure 4b and Figure 4c In the above, the basic paths 40b and 40c are superimposed by the simple trigonometric function 41b and the simple rectangular function 41c, respectively. The trigonometric function 41b and the rectangular function 41c also have significantly smaller amplitudes and shorter periods than the basic paths 40b and c, resulting in the superimposed functions 42b and 42c.

[0078] Figure 5a and Figure 5b A flowchart illustrating a preferred embodiment of the method according to the present invention is provided.

[0079] according to Figure 5a The method described herein, in step 610, firstly provides a contact lens blank having a front side and a rear side. Then, in step 620, it provides morphological data describing the shape of the user's eye.

[0080] Then, based on the topographic data, a support region for the contact mirror is formed in step 650, and then an additional three-dimensional surface structure is formed on the support region in step 660.

[0081] Optionally, optical data may be provided in step 630 for correcting the user's optical defect vision by forming the optically active area of ​​the contact lens in step 640.

[0082] It should be noted that, to the extent technically possible, the steps performed in the method according to the invention need not necessarily be... Figure 5a The sequence of execution is described in the text.

[0083] Therefore, when optical data is additionally used, it is conceivable that steps 630 and 640 have been performed before the topography data is provided in step 620. Alternatively, steps 630 and 640 may also be performed after step 650 or after step 660.

[0084] It is also conceivable that the formation of the optically active region on the rear side of the lens, performed in step 640, and the formation of the support region and / or additional three-dimensional surface structures according to step 650, are carried out in a single processing step.

[0085] Figure 5b The methods of depiction in the middle and Figure 5a The difference in the method described in the previous section is that, after providing topographic data in step 620, three-dimensional surface structure data is provided in step 670, and then in step 680, this data is overlaid with the topographic data to generate a fused dataset. Then, in step 690, a support region is formed based on the fused dataset.

[0086] Optionally, optical data may be provided in step 630 for correcting the user's optical defect vision by forming the optically active area of ​​the contact lens in step 640.

[0087] about Figure 5b It should also be noted that, to the extent technically possible, the steps performed in the method according to the invention need not necessarily be... Figure 5b The sequence of execution is described in the text.

[0088] Therefore, when optical data is used additionally, it is conceivable that steps 630 and 640 have been performed before the topography data is provided in step 620. Alternatively, steps 630 and 640 may also be performed after step 670, after step 680, or after step 690.

[0089] Furthermore, the formation of the optically active region on the rear side of the lens, performed in step 640, can be carried out in a single processing step along with the formation of the support region based on the fusion dataset according to step 690.

[0090] Figure 6A schematic depiction of a molding method 600-640 for producing a contact lens 63 using a mold constructed according to the invention is shown, having schematic depictions of various embodiments of surface structures 17a-17e on the support region 63a of the contact lens 63 produced by the method.

[0091] In step 600, a concave mold half 60 is provided, the surface 60a of which is used to form the front side of the contact lens 63. In step 610, starting material for producing the lens 63 is then introduced into the concave mold half 60 and distributed in the concave mold half 60 in step 620. In step 630, a convex mold half 61 having surface 61a is introduced into the concave mold half 60 and pressed against it, thereby shaping the starting material 65 disposed between the mold halves 60 and 61 into the shape of the contact lens 63. The mold halves 60 and 61 are then separated from each other, and the formed contact lens 63 can be removed, see step 640.

[0092] In this case, according to the invention, the edge region 61b of the surface 61a of the punch half 61 has been formed using a fusion dataset, which has been generated by overlaying topographic data with data of a three-dimensional surface structure, the topographic data representing an inverse image of the three-dimensional topography of the user's eye in at least the area covered by the support region 63a of the contact lens 63 when the contact lens 63 is worn.

[0093] In this way, when Figure 6 In step 630 of the outlined molding method, when forming the support region 63a of the contact mirror 63, the desired three-dimensional surface structure is then formed in the support region. Figure 6 In, as previously in Figure 2 As in the example, various examples of three-dimensional surface structures 17a-17e are reproduced.

Claims

1. A method for forming a support area (17) of a contact lens (10) adapted to an individual user, wherein the support area (17) of the contact lens (10) is the area where the contact lens (10) rests on the user's eye when the contact lens (10) is worn, the method comprising: Provided (610) a contact lens blank having a rear side (12) and a front side (11), the rear side (12) facing the user's eyes when the contact lens (10) is worn, and the front side (11) facing away from the eyes when the contact lens (10) is worn. Provides (620) topographic data, the topographic data representing an inverse image of the three-dimensional topography of the user's eye in at least the area covered by the support area (17) of the contact lens (10) when the contact lens (10) is worn. Based on the topographic data, a support area (17) is formed (650) on the surface of the rear side (12) of the contact mirror (10), and An additional three-dimensional surface structure (17a-17e) is formed (660) on the support area (17) of the contact mirror (10). When the contact lens (10) is worn, the support area (17) of the contact lens (10) rests on the user's eye in the form of a surface defined by an inverse image of the three-dimensional topography of the eye superimposed with the three-dimensional surface structure (17a-17e).

2. The method according to claim 1, Its features are, The formation (650) of the support region (17) and / or the formation (660) of the three-dimensional surface structure (17a-17e) are carried out by material removal processing following a substantially spiral path (30).

3. The method according to claim 1, wherein, Prior to the formation (650) of the support region, the method further includes: Provide data on the three-dimensional surface structures (17a-17e) described in (670), and A fused dataset (680) is generated by overlaying the topographic data with the data of the three-dimensional surface structure (17a-17e). The formation of the support region (690) is based on the fused dataset.

4. The method according to claim 3, Its features are, The generation of the fused dataset (680) includes the spatial overlay of the topographic data and the data of the three-dimensional surface structure (17a-17e).

5. The method according to claim 3 or 4, Its features are, The formation (690) of the support region based on the fused dataset is carried out by a material removal process following a substantially spiral path (30).

6. The method according to claim 5, Its features are, The proportion of the data of the three-dimensional surface structures (17a-17e) in the fused dataset is mapped by the motion variation of the machining tool with respect to the joint angle and / or joint depth.

7. A method for manufacturing a contact lens (10), comprising: Provided (610) a contact lens blank having a rear side (612) and a front side (11), the rear side (612) facing the user's eyes when the contact lens (10) is worn, and the front side (11) facing away from the eyes when the contact lens (10) is worn. Provide (630) optical data representing the aberrations of the user's eye to be corrected by the contact lens (10). Based on the optical data, an optically active region (15) (640) is formed on the rear side (12) of the contact lens (10), and The support area (17) is formed using the method according to any one of claims 1 to 6.

8. The method according to claim 7, Its features are, The formation of the optically active region (12) (640) and the formation of the support region (17) are carried out in one processing step of the contact lens blank.

9. The method according to claim 7 or 8, Its features are, The formation of the optically active region (640) and the support region (17) is carried out by a material removal process following a spiral path (30).

10. A method for producing a mold (61) for manufacturing a contact lens (63) by means of molding methods (600-640), the method comprising: The portion (61b) of the mold (61) corresponding to the support area (63a) on the rear surface of the contact lens (63) to be manufactured, facing the user's eye, wherein the support area (63a) of the contact lens (63) to be manufactured is the area where the contact lens (63) rests on the user's eye when the contact lens (63) is worn. The formation is performed using a fusion dataset, which is generated by overlaying topographic data with data of three-dimensional surface structures (17a-17e), the topographic data representing an inverse image of the three-dimensional topography of the user's eye in at least the area covered by the support area (63a) of the contact lens (63) when the contact lens (63) is worn.

11. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structure (17a-17e) has an amplitude in the range of 0.01-0.5 mm, preferably in the range of 0.05-0.3 mm, when viewed from the rear side (12) of the contact lens (10, 63) to the front side (11) of the contact lens (10, 63).

12. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structure (17a-17e) is formed in such a way that the support surface resting on the user's eyes in the support area (17, 63a) is at most 70%, preferably at most 50%, and particularly preferably at most 30% of the total area of ​​the support area (17, 63a).

13. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structure (17a-17e) has a periodicity of approximately 2π / n when viewed in the circumferential direction of the contact mirror (10, 63), where n is a natural number.

14. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structures (17a-17e) essentially correspond to a random distribution (17a).

15. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structure (17a-17e) corresponds to at least a single continuous, preferably a triple continuous three-dimensional function on the support region (17, 63a).

16. The method according to any one of the preceding claims, Its features are, The support region (17, 63a) is essentially C2 continuous.

17. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structure (17a-17e) includes at least one annular surface, which is modulated by a sine function in the circumferential direction.

18. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structure (17a-17e) includes a plurality of concentric annular surfaces, which are preferably separated from each other by annular grooves.

19. The method according to any one of the preceding claims, Its features are, Viewed from the center (13) of the lens (10, 63), the three-dimensional surface structure (17b) corresponds to the superposition of a first sine function in the radial direction and a second sine function in the circumferential direction.

20. The method according to any one of the preceding claims, Its features are, The three-dimensional surface structures (17a-17e) are selected from a library of predefined surface structures (17a-17e) based on the morphological data.

21. A contact lens (10) adapted to individual users. Its features are, The contact lens has been produced by the method according to any one of the preceding claims.

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