Method for polishing surface
By providing protective cover on the non-polished area of the ophthalmic lens, the optical function attenuation problem caused by surface irregularity is solved, and higher lens accuracy and optical performance are achieved.
Patent Information
- Application Number
- CN202411201242.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2023-08-31
- Filing Date
- 2024-08-29
- Publication Date
- 2025-02-28
AI Technical Summary
In the prior art, when manufacturing ophthalmic lenses, it is difficult to effectively reduce surface irregularities, resulting in optical function attenuation and undesired color effects.
Deterioration of the non-polished area is avoided by providing a protective covering on the non-polished area that needs protection, covering at least one non-polished area and polishing the surface outside the cover in the polishing step.
It effectively avoids deterioration of the non-polished area, reduces surface irregularities, and improves the optical function and accuracy of the lens.
Smart Images
Figure CN119526130A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of ophthalmology and relates to a method for manufacturing an ophthalmic device, comprising a polishing step for the surface of a mold or an ophthalmic lens or a semi-finished lens. The invention also relates to an intermediate mold intended for molding an ophthalmic lens. The invention also relates to a finished ophthalmic lens or a semi-finished ophthalmic lens. Background Art
[0002] Typically, spectacle lenses are specifically manufactured according to the needs of each wearer, which spectacle lenses may take the form of specifications defined in a prescription drawn up by an ophthalmologist or optometrist.
[0003] To manufacture a lens, a lens blank undergoes various steps (particularly a surfacing step, also called a cutting step) to form the desired lens, during which the shape of the lens blank is processed to produce what may be called a surface-processed lens, so that the surface-processed lens exhibits the desired optical properties. The shape of the surface of the lens or lens blank may be obtained by direct cutting of the surface, or may be obtained by molding through a mold previously cut according to the desired optical properties.
[0004] In practice, the operation may be performed, for example, on a blank or semi-finished lens blank whose front surface has been previously machined, the surface machining operation essentially affecting one of the surfaces of the lens blank, typically the back surface, according to the prescription.
[0005] In addition to the desired desired optical properties, the surface quality obtained must be such that no irregularities occur which would be transmitted to the resulting product and cause deviations from the desired desired optical properties. In fact, the resulting product may be very sensitive to these surface irregularities. Therefore, a method is needed that enables these surface irregularities to be reduced.
[0006] Irregularities can have various origins. In particular, when the cutting step is done by diamond turning, these irregularities can appear at the edge or in the center due to cutting instabilities. Even if the overall form may be fine and the roughness very close to the optical element specifications, irregularities can cause undesirable color effects on the surface, such as CD or rainbow effects or subtle rings.
[0007] A way to limit these irregularities is to polish the surface of the lens or lens blank after the cutting step. However, in the case of surface discontinuities (such as protrusions, microstructures, patterns...), the polishing step may result in an undesirable reduction in sharpness, thereby attenuating the desired optical function.
[0008] Therefore, one option is to polish the protrusions but reduce the quality. Another solution is to keep the cut surface unpolished but with some color effect.
[0009] To demonstrate the undesirable effect, Figure 1 1 shows a side view of an ophthalmic device manufactured by a method according to the prior art. Specifically, Figure 1 2 represents a protrusion of an ophthalmic device. The dotted line 20 is the protrusion cut by diamond turning before polishing, and the line 22 is the protrusion after polishing. The protrusion after polishing does not maintain the desired shape obtained by cutting before polishing, and therefore does not have the desired optical function.
[0010] What is needed is a method and system for directly addressing irregularities introduced by surface machining tools to improve the accuracy of the final lens and reduce rejected lenses. Summary of the invention
[0011] This object is achieved according to the present disclosure by a method for manufacturing an ophthalmic device, the method comprising a polishing step to polish a surface of the ophthalmic device comprising at least one non-polished area. The at least one non-polished area is an area that is intended not to be polished. The polishing step comprises:
[0012] - covering, during which a protective covering is placed on the surface to cover at least one non-polished area;
[0013] - polishing at least a portion of the surface; and
[0014] -Remove protective covering.
[0015] Due to the present disclosure, degradation of the non-polishing area may be avoided by covering at least one non-polishing area.
[0016] The ophthalmic device may be a mold or an insert intended for manufacturing an ophthalmic lens or a semi-finished ophthalmic lens. The ophthalmic device may be an ophthalmic lens.
[0017] Ophthalmic lenses can be progressive addition lenses (PAL) or lenses for myopia reduction or plano lenses (no correction).
[0018] The at least one non-polished area may be a microelement, a protrusion, a microlens, an engraving, a groove, a discontinuity, a pattern, a figure, a scattering element, a shape.
[0019] At least one non-polished area can be at least one cavity or at least one concave microelement of an ophthalmic lens or a mold for manufacturing an ophthalmic lens. In this embodiment, the protective cover can fill the cavity or the concave microelement, in other words, the material of the protective cover can fill the cavity or the concave microelement.
[0020] The microelements can be convex or concave, spherical or aspherical, bifocal or monofocal, or pi-Fresnel.
[0021] For example, due to the present disclosure, when the non-polished areas are protrusions, degradation of the protrusions and thus, for example, color effects may be avoided by covering at least one non-polished area. Advantageous and convenient features of the manufacturing method are described below.
[0022] The covering may be a tape application. The protective covering may be a protective tape.
[0023] The protective covering may be a film deposited on the surface so as to cover at least one non-polished area.
[0024] The protective covering may be at least a layer made by an additive manufacturing process such as fused deposition modeling (FDM), SLS selective laser sintering, particle FDM, multi jet fusion (MJF), material jetting (MJ).
[0025] The coating can be applied by inkjet or spin coating.
[0026] The covering can be made by additive manufacturing processes such as fused deposition modeling (FDM), SLS selective laser sintering, particle FDM, multi jet fusion (MJF), material jetting (MJ).
[0027] At least a portion of the polishing surface may be a portion of the polishing surface not covered by the protective covering.
[0028] At least a portion of the polishing surface may polish a portion of the surface not covered by the protective covering. The polishing may be uniform over the portion of the surface not covered by the protective covering. In other words, the material stock removal by the polishing process may be uniform over the uncovered surface.
[0029] During polishing, material from the surface may be removed.
[0030] During polishing, material not covered by the protective covering may be removed.
[0031] The thickness of the removed material may be less than 20 μm, less than 1 μm, preferably less than 0.1 μm.
[0032] The surface comprising at least one non-polished area may be the surface of a mold intended for molding an ophthalmic lens.
[0033] Prior to the polishing step, the surface of the mold may be coated with NiP or a ferrous material.
[0034] The surface including at least one non-polished area may be the surface of a semi-finished lens or a finished lens.
[0035] Prior to the polishing step, a surface machining step may be included during the manufacturing method. The surface machining step uses a tool to surface the surface of the ophthalmic device. The tool is made of a first material and is fixed by a carrier element made of a second material. The first material has a higher hardness than the second element.
[0036] For example, the tool may be a diamond tool.
[0037] The thickness of the protective covering may be greater than 10 μm. The thickness of the protective covering may be greater than 20 μm. The thickness of the protective covering may be between 10 μm and 350 μm.
[0038] The thickness of the protective cover is greater than 10 μm, which allows avoiding the removal of all the protective cover during the polishing step. In practice, in the field of polishing of ophthalmic elements, at least 10 μm of material are removed during polishing.
[0039] The thickness of the protective cover on the edges may be less than 200 μm.
[0040] The thickness of the protective cover on the edges may be less than 100 μm.
[0041] The thickness of the protective cover on the edges may be less than 5 μm.
[0042] The thickness of the protective cover on the edges may be as thin as possible to ensure surface continuity between the polished surface and the non-polished area.
[0043] The non-polished area can be defined by a mask. The mask can have different types of geometries, like cylindrical or semi-cylindrical or any type of shape.
[0044] According to a second aspect, the present disclosure also provides an intermediate mold intended for manufacturing an ophthalmic lens. The intermediate mold may include: a metal block; a surface of the metal block, the surface including at least one non-polished area; and a protective cover disposed on a portion or all of the at least one non-polished area.
[0045] An intermediate mold comprising a metal block may include a coating having at least one discontinuity.
[0046] According to a third aspect, the present disclosure also provides an ophthalmic lens. The ophthalmic lens comprises: a surface comprising at least one non-polished area; and a protective cover disposed on a portion or all of the at least one non-polished area.
[0047] According to a fourth aspect, the present disclosure also provides a semi-finished ophthalmic lens. The semi-finished ophthalmic lens comprises: a surface comprising at least one non-polished area; and a protective cover disposed on a portion or all of the at least one non-polished area. BRIEF DESCRIPTION OF THE DRAWINGS
[0048] The description of the present disclosure now continues with a detailed description of advantageous embodiments presented below, by way of non-limiting examples and with reference to the accompanying drawings.
[0049] Figure 1 An ophthalmic device manufactured by a method according to the prior art is represented.
[0050] Figure 2A and Figure 2B is a flow chart illustrating methods according to two embodiments of the present disclosure.
[0051] Figure 3A , Figure 3B and Figure 3C Shown are top and side views, respectively, of an ophthalmic device with a protective cover according to two embodiments of the present disclosure. DETAILED DESCRIPTION
[0052] In the following description, the drawings are not necessarily drawn to scale and certain features may be shown in generalized or schematic form for the purposes of clarity and simplicity or for information purposes. In addition, although making and using various embodiments are discussed in detail below, it should be understood that many inventive concepts are provided as described herein that can be implemented in a wide variety of contexts.
[0053] The embodiments discussed herein are merely representative and do not limit the scope of the present invention. It is also obvious to those skilled in the art that all technical features defined relative to the method can be transposed to the device individually or in combination, and conversely, all technical features relative to the device can be transposed to the method individually or in combination.
[0054] To avoid detail not necessary to practice the invention, the description may omit certain information known to those skilled in the art.
[0055] The present disclosure relates to a method for manufacturing an ophthalmic device, the method comprising a polishing step to polish a surface of the ophthalmic device, the surface comprising at least one non-polished area, the at least one non-polished area being an area that is intended not to be polished.
[0056] The ophthalmic device can be a lens, a single-vision lens, a bifocal lens, a progressive lens, a semi-finished lens, a mold or an insert, which is intended for manufacturing a lens, a single-vision lens, a bifocal lens, a progressive lens, a semi-finished lens. The ophthalmic device can be used in the field of single vision, bifocal lens, progressive lens, plano lens or myopia reduction.
[0057] The at least one non-polished area may be a microelement, a protrusion, a microlens, an engraving, a groove, a discontinuity, a pattern, a figure, a scattering element, a shape.
[0058] At least one non-polished area can be a cavity or a concave microelement. It can be at least one cavity or at least one concave microelement of an ophthalmic lens or a mold for making an ophthalmic lens.
[0059] The protective covering may fill the cavities or the concave microelements, in other words, the material of the protective covering may fill the cavities or the concave microelements.
[0060] The microelements can be convex or concave, spherical or aspherical, bifocal or monofocal, or pi-Fresnel.
[0061] The non-polished area can be an aesthetic feature or a technical feature for alleviating myopia or a technical feature for correcting visual defects.
[0062] Figure 2A The steps of the method of the present disclosure are shown.
[0063] Polishing steps include:
[0064] - Covering 10, during which a protective covering is provided on the surface to cover at least one non-polished area;
[0065] - polishing 12 at least a portion of the surface; and
[0066] - Remove 14 protective coverings.
[0067] Due to the present disclosure, degradation of the non-polishing area may be avoided by covering at least one non-polishing area.
[0068] For example, due to the present disclosure, when the non-polished areas are protrusions, degradation of the protrusions and thus, for example, color effects may be avoided by covering at least one non-polished area. Advantageous and convenient features of the manufacturing method are described below.
[0069] The covering may be a tape. The protective covering may be a protective tape, such as an adhesive film.
[0070] The protective covering may be a film deposited on the surface so as to cover at least one non-polished area.
[0071] The protective cover may be at least a layer made by an additive manufacturing process such as fused deposition modeling (FDM), SLS selective laser sintering, particle FDM, multi jet fusion (MJF), material jetting (MJ). The cover may be applied by inkjet, spin coating or aerosol.
[0072] The covering can be made by additive manufacturing processes such as fused deposition modeling (FDM), SLS selective laser sintering, particle FDM, multi jet fusion (MJF), material jetting (MJ).
[0073] A coating may be a material that changes state after application, for example from a gas or liquid to a solid.
[0074] For coverage, a mask may be used to define non-polished areas while leaving the rest of the ophthalmic device uncovered.
[0075] The protective covering can be a pressure sensitive adhesive tape or polycarbonate or glue or ink or any kind of material that can have the desired characteristics.
[0076] Desired characteristics of the protective covering may be thickness or adhesion criteria.
[0077] The thickness of the protective cover on the edges may be less than 200 μm.
[0078] The thickness of the protective cover on the edges may be less than 100 μm.
[0079] The thickness of the protective cover on the edges may be less than 5 μm.
[0080] The thickness of the protective cover on the edges may be as thin as possible to ensure surface continuity between the polished surface and the non-polished area.
[0081] The adhesion criteria of the protective covering can be determined by considering at least one of the following parameters:
[0082] - parameters of the polishing step (such as polishing material, polishing duration, ...),
[0083] -Polished materials, such as metal or glass or polymers...
[0084] - adhesion to the polished material so that the protective sequence is not removed during the polishing step,
[0085] - adhesion to the polished material so that the protective sequence can be easily and properly removed during the removal step,
[0086] - A compromise between not removing during the polishing step and being easily and properly removed during the removal step
[0087] The thickness of the protective covering can be determined by considering at least one of the following parameters:
[0088] -Polished materials, such as metal or glass or polymers...
[0089] - Protective covering material, such as polycarbonate...
[0090] - Parameters of the polishing step: polishing material, polishing duration, ...
[0091] - Type of non-polished area
[0092] According to one embodiment, the thickness of the protective cover may be greater than 10 μm.
[0093] According to one embodiment, the thickness of the protective cover may be greater than 20 μm.
[0094] According to one embodiment, the thickness of the protective cover may be between 10 μm and 350 μm.
[0095] The thickness of the protective cover is greater than 10 μm, which allows avoiding the removal of all the protective cover during the polishing step. In practice, in the field of polishing of ophthalmic elements, at least 10 μm of material are removed during polishing.
[0096] The thickness of the protective cover on the edges may be less than 200 μm.
[0097] The thickness of the protective cover on the edges may be less than 100 μm.
[0098] The thickness of the protective cover on the edges may be less than 5 μm.
[0099] The thickness of the protective cover on the edges may be as thin as possible to ensure surface continuity between the polished surface and the non-polished area.
[0100] At least a portion of the polishing surface may be a portion of the polishing surface not covered by the protective covering.
[0101] At least a portion of the polishing surface may polish a portion of the surface not covered by the protective covering. The polishing may be uniform over the portion of the surface not covered by the protective covering. In other words, the material stock removal by the polishing process may be uniform over the uncovered surface.
[0102] During polishing, material from the surface may be removed.
[0103] During polishing, material not covered by the protective covering may be removed.
[0104] The thickness of the removed material may be less than 20 μm, less than 1 μm, preferably less than 0.1 μm.
[0105] Removal can be chemical (such as solvents or alcohol) and / or mechanical (such as manual methods, ultrasonic baths or wiping with a cloth).
[0106] The surface comprising at least one non-polished area may be the surface of a mold intended for molding an ophthalmic lens.
[0107] Prior to the polishing step, the surface of the mold may be coated with NiP or a ferrous material.
[0108] The surface including at least one non-polished area may be the surface of a semi-finished lens or a finished lens.
[0109] The present disclosure relates to a method for manufacturing an ophthalmic device, the method comprising a machining step to obtain a desired surface of the ophthalmic device. The machining step may be a cutting step, also referred to as a surface machining step. The machining step may be a molding step or a replication step.
[0110] Figure 2B A method according to an embodiment of the present disclosure, alone or in combination, is shown, the method comprising a surface processing 16 step.
[0111] Therefore, according to this embodiment, alone or in combination, a surface processing 16 step can be included during the manufacturing method before the polishing step. The surface processing step uses a tool to surface process the surface of the ophthalmic device. The tool is made of a first material and is fixed by a carrier element made of a second material. The first material has a higher hardness than the second element.
[0112] For example, the tool may be a diamond tool.
[0113] According to a second aspect, the present disclosure also provides an intermediate mold intended for manufacturing an ophthalmic lens. The intermediate mold may include: a metal block; a surface of the metal block, the surface including at least one non-polished area; and a protective cover disposed on a portion or all of the at least one non-polished area.
[0114] An intermediate mold comprising a metal block may include a coating having at least one discontinuity.
[0115] According to a third aspect, the present disclosure also provides an ophthalmic lens. The ophthalmic lens comprises: a surface comprising at least one non-polished area; and a protective cover disposed on a portion or all of the at least one non-polished area.
[0116] Figure 3A , Figure 3B and Figure 3C Shown are top and side views, respectively, of an ophthalmic device with a protective cover according to two embodiments of the present disclosure.
[0117] exist Figure 3A , the ophthalmic device 30 includes a base 36. As illustrated, the ophthalmic device 30 may include additional micro-elements 32 concentrically arranged on a portion of the base. Figure 3A The side view is based on Figure 3B and Figure 3C The two embodiments shown in Figure 3 are respectively shown, where the micro-components are convex and concave. The base can be flat or curved (spherical or aspherical, symmetrical or asymmetrical). As shown, the micro-components can be partially covered with a protective cover 32. The covered micro-components are non-polished areas.
[0118] When the ophthalmic device is an ophthalmic lens, the base may be "plano" (ie, no optical power) or have optical power (monofocal, bifocal, progressive focus).
[0119] The ophthalmic lens 30 may include an additional microlens 32 arranged concentrically on a portion of the base. The microlens 32 may be a non-polished area. The microlens 32 may be covered by a tape 34 to protect it during the polishing step.
[0120] According to a fourth aspect, the present disclosure also provides a semi-finished ophthalmic lens. The semi-finished ophthalmic lens comprises: a surface comprising at least one non-polished area; and a protective cover disposed on a portion or all of the at least one non-polished area.
[0121] Numerous additional modifications and variations will occur to those skilled in the art upon reference to the foregoing illustrative embodiments, which are presented by way of example only and are not intended to limit the scope of the invention, which is determined solely by the appended claims.
[0122] In the claims, the word "comprising" does not exclude other elements or steps and the indefinite article "a or an" does not exclude a plurality. The mere fact that different features are recited in mutually different dependent claims does not indicate that a combination of these features cannot be used to advantage. Any reference signs in the claims shall not be construed as limiting the scope of the invention as defined in the set of claims.
Claims
1. A method for manufacturing an ophthalmic device, the method comprising a polishing step to polish a surface of the ophthalmic device including at least one non-polished area, the at least one non-polished area being an area intended not to be polished, the polishing step comprising - covering (10), during which a protective covering is provided on the surface to cover the at least one non-polished area; - polishing (12) at least a portion of said surface; - Removing (14) the protective covering.
2. The method according to claim 1, wherein: The cover (10) is an adhesive tape and the protective cover is a protective tape.
3. The method according to claim 1, wherein: The cover (10) is applied by inkjet or spin coating.
4. The method according to any one of the preceding claims, wherein: The polishing (12) of at least a portion of the surface polishes a portion of the surface not covered by the protective covering.
5. The method according to any one of claims 1 to 4, wherein: Said surface comprising said at least one non-polished area is a surface of a mold intended for the manufacture of an ophthalmic lens.
6. The method according to claim 5, wherein: Before the polishing (12) step, the surface of the mold is coated with NiP or a ferrous material.
7. The method according to any one of claims 1 to 4, wherein: The surface comprising the at least one non-polished area is a surface of a semi-finished lens or a finished lens.
8. The method according to any one of the preceding claims, comprising, before the polishing (12) step, a surface machining (16) step by using a tool, The tool is made of a first material and is fixed by a carrier element made of a second material, The first material has a higher hardness than the second member.
9. The method according to claim 8, wherein: The tool is a diamond tool.
10. The method according to any of the preceding claims, wherein: The at least one non-polished area is a microelement, a protrusion, a microlens, an engraving, a groove, a discontinuity, a pattern, a figure, a scattering element, a shape.
11. A method according to any one of the preceding claims, wherein: The protective cover has a thickness greater than 10 μm.
12. A method according to any one of the preceding claims, wherein: The non-polishing area is defined by a mask.
13. An intermediate mold intended for use in the manufacture of an ophthalmic lens, said intermediate mold comprising - Metal blocks; - a surface of said metal block, said surface comprising said at least one non-polished area; - a protective covering disposed over a portion or the entirety of the at least one non-polishing area.
14. An ophthalmic lens comprising - a surface comprising at least one non-polished area; - a protective covering disposed over a portion or the entirety of the at least one non-polishing area.
15. A semi-finished ophthalmic lens comprising - a surface comprising at least one non-polished area; - a protective covering disposed over a portion or the entirety of the at least one non-polishing area.