Eyeglass lens manufacturing method, eyeglass lens, and eyeglasses

Abstract

Provided are a method for manufacturing a spectacle lens and technologies related thereto. The method for manufacturing a spectacle lens, in which marking for performing desired processing by laser irradiation is performed on one surface of a spectacle lens having an object-side surface and an eyeball-side surface on which antireflection films different from each other are respectively provided, comprises: a step for determining an applicable wavelength of a laser to be used; and a step for selecting a surface, on which an antireflection film having relatively low reflectance with respect to the applicable wavelength is provided, out of the object-side surface and the eyeball-side surface, and irradiating the selected surface with a laser using the applicable wavelength.

Description

[Technical Field]

[0001] The present invention relates to a method for manufacturing a spectacle lens, a spectacle lens, and spectacles. [Background technology]

[0002] Patent Document 1 discloses a plastic lens for spectacles characterized by having an antireflection coating consisting of seven layers, with low refractive index layers and high refractive index layers alternately laminated on a plastic substrate, the antireflection coating having a design dominant wavelength λ0 in the range of 480 nm to 550 nm, and numbering the layers in order outward, starting with the layer closest to the substrate as the first layer, with odd-numbered layers being SiO2 layers and even-numbered layers being TiO2 layers, the total film thickness of the first to third layers being set in the range of 180 nm to 250 nm, the physical film thickness ratio between the SiO2 layers and the TiO2 layers being in a specified relationship, and the optical film thicknesses of the layers being in a specified relationship. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 3988504 Summary of the Invention [Problem to be solved by the invention]

[0004] It is known that marks and letters relating to the type and prescription of spectacle lenses are engraved on the lens surface, etc. These are formed by a marking method that does not obstruct the wearer's vision.

[0005] On the other hand, in addition to the above purposes, it is also conceivable to provide design effects, identification effects, brand strategic effects, etc. by applying marks such as predetermined letters, symbols, and designs on the lenses.

[0006] One method for forming desired patterns such as letters on eyeglass lenses is to remove part of a film formed on the lens surface by irradiating it with laser light.

[0007] Many commercially available eyeglass lenses have an anti-reflection function for visible light on their surfaces (for example, Patent Document 1). Anti-reflection coatings are designed primarily to enable eyeglass wearers to obtain a clear field of vision.

[0008] On the other hand, anti-reflection coatings on eyeglass lenses do not necessarily have anti-reflection properties for wavelengths outside the visible light range, such as the short wavelength side (for example, the ultraviolet range with wavelengths of 400 nm or less) or the long wavelength side (for example, the infrared range with wavelengths of 800 nm or more), and many lenses have a reflectance of more than 10%.

[0009] On the other hand, when performing processing using a laser, if the wavelength of the processing laser is in the ultraviolet or infrared range, the energy from the irradiation may not sufficiently reach the target material to be removed, which can make precise processing difficult.

[0010] On the other hand, it was found that if the laser output is increased, the processing becomes uneven, damage occurs below the membrane that is being removed, and the damaged area obstructs the wearer's field of vision or causes the membrane to peel off.

[0011] The present disclosure aims to provide a technology that enables precise processing of eyeglass lenses that have anti-reflection coatings on both the object-side surface and the eyeball-side surface efficiently and under stable conditions. Another object of the present disclosure is to provide a spectacle lens that is provided with an anti-reflection coating on both the object-side surface and the eyeball-side surface and that is also decorated. [Means for solving the problem]

[0012] A first aspect of the present invention is A method for manufacturing a spectacle lens, the method comprising: irradiating one surface of the spectacle lens with a laser to perform marking for desired processing, the spectacle lens having anti-reflection films different from each other on the object-side surface and the eyeball-side surface, the method comprising: determining the applicable wavelength of the laser to be used; selecting a surface from the object-side surface and the eyeball-side surface on which an anti-reflection film having a relatively low reflectance at the applicable wavelength is to be provided; The method for manufacturing a spectacle lens includes irradiating the selected surface with a laser beam using the applicable wavelength.

[0013] A second aspect of the present invention is A method for manufacturing eyeglass lenses, in which a desired marking process is performed by irradiating one surface of an eyeglass lens, the object-side surface and the eyeball-side surface of which are provided with different anti-reflection films, with a laser, This is a method for manufacturing eyeglass lenses, which involves selecting one of the object-side surface and the eyeball-side surface that has a relatively low reflectance for light in a predetermined wavelength range, and applying laser light having a wavelength within the predetermined wavelength range to the selected surface to perform laser irradiation.

[0014] A third aspect of the present invention is In the method for manufacturing a spectacle lens according to the first or second aspect, the applicable wavelength or the wavelength within the predetermined wavelength range is within a range of 200 to 400 nm, or within a range of 800 to 1100 nm.

[0015] A fourth aspect of the present invention is This is a method for manufacturing a spectacle lens according to any one of the first to third aspects, wherein the anti-reflection film on the selected surface has a reflectance of 10% or less for the applicable wavelength or wavelengths within the predetermined wavelength range.

[0016] A fifth aspect of the present invention is This is a method for manufacturing a spectacle lens according to any one of the first to fourth aspects, wherein the anti-reflection film on the selected surface has a reflectance at the applicable wavelength or wavelengths within the predetermined wavelength range that is 10% or more lower than that of the other surface.

[0017] A sixth aspect of the present invention is a method for manufacturing a semiconductor device comprising: A method for manufacturing a spectacle lens, comprising: irradiating an antireflection coating having a multilayer structure including a stack of low refractive index layers and high refractive index layers, the antireflection coating being formed so as to cover an optical surface of a lens substrate, with an ultrashort pulse laser; and partially removing predetermined layers including an outermost layer of the multilayer structure, thereby performing desired laser processing; The method for manufacturing a spectacle lens described in any one of claims 1 to 5, wherein the antireflection film on the selected surface includes a reactive layer that is relatively more reactive to irradiation with the ultrashort pulse laser than other layers included in the multilayer structure, and the laser processing that can be seen with visible light is performed by performing a removal step in which the reactive layer is at least partially removed by the irradiation.

[0018] A seventh aspect of the present invention is A seventh aspect of the present invention is a method for manufacturing a spectacle lens according to the seventh aspect, wherein the ultrashort pulse laser has a pulse width of 10 femtoseconds or more and less than 100 picoseconds.

[0019] An eighth aspect of the present invention is A spectacle lens having different anti-reflection films on the object-side surface and the eyeball-side surface, and having laser marking on one surface of the spectacle lens, The spectacle lens has an anti-reflection film provided on one surface that has a lower reflectance for light with a wavelength of at least 200 to 400 nm than the anti-reflection film provided on the other surface.

[0020] A ninth aspect of the present invention is a method for manufacturing a semiconductor device comprising: A spectacle lens having different anti-reflection films on the object-side surface and the eyeball-side surface, and having laser marking on one surface of the spectacle lens, The spectacle lens has an anti-reflection film provided on one surface that has a lower reflectance for light with a wavelength of at least 800 to 1100 nm than the anti-reflection film provided on the other surface.

[0021] A tenth aspect of the present invention is a method for manufacturing a semiconductor device comprising: The eyeglass lens is a lens substrate having an optical surface; an anti-reflection film covering the optical surface of the lens substrate; the antireflection film has a multilayer structure including a stack of a low refractive index layer and a high refractive index layer, the antireflection film includes a reactive layer that is relatively more reactive to irradiation with an ultrashort pulsed laser than other layers included in the antireflection film; In the spectacle lens according to the eighth or ninth aspect, a marking is provided in a removed area formed by at least partially removing a predetermined layer including an outermost layer of the multilayer structure, so that the removed area can be seen with visible light by exposing the high refractive index layer below the reactive layer or a partially remaining reactive layer.

[0022] An eleventh aspect of the present invention is a pair of glasses in which a spectacle lens manufactured by the spectacle lens manufacturing method according to any one of the first to seventh aspects, or a spectacle lens according to any one of the eighth to tenth aspects, is fitted into a frame. [Effects of the Invention]

[0023] According to the present invention, it is possible to carry out precise processing efficiently under stable conditions on a spectacle lens having anti-reflection coatings on both the object-side surface and the eyeball-side surface. Furthermore, according to the present invention, it is possible to provide a spectacle lens in which an anti-reflection film is provided on both the object-side surface and the eyeball-side surface, and which is also decorated by laser processing. [Brief explanation of the drawings]

[0024] [Figure 1] FIG. 1 is a plan view showing an example of processing of a spectacle lens according to an embodiment of the present invention. [Figure 2] FIG. 2 is a flow chart showing an example of the procedure of a method for manufacturing a spectacle lens according to one embodiment of the present invention. [Figure 3] FIG. 3 is a side cross-sectional view showing an example of a laminated structure of thin films in a spectacle lens according to one embodiment of the present invention. [Figure 4A]FIG. 4A is an explanatory diagram showing an example of the schematic configuration of a laser processing device used in a method for manufacturing eyeglass lenses according to one embodiment of the present invention, and shows how the device is configured to include a laser light source unit, an AOM (Acousto Optics Modulator) system unit, a beam shaper unit, a galvanometer scanner unit, and an optical system, and to irradiate an AR film with laser light via each of these units. [Figure 4B] FIG. 4B is an explanatory diagram showing an example of the schematic configuration of a laser processing device used in a method for manufacturing eyeglass lenses according to one embodiment of the present invention, and shows how the device is configured so that irradiation of an AR film with laser light (i.e., an ultrashort pulse laser) via an optical system or the like can be performed in a defocused setting. [Figure 5A] FIG. 5A is an explanatory diagram showing an example of the configuration of the main parts of a spectacle lens according to one embodiment of the present invention, and is an explanatory diagram showing an example of the configuration of the main parts of a spectacle lens according to this embodiment. [Figure 5B] FIG. 5B is an explanatory diagram showing an example of the configuration of the main part of a spectacle lens according to one embodiment of the present invention, showing a specific example of the results of observation of a cross section of an AR film with an electron microscope. [Figure 6A] FIG. 6A is a photograph showing the result of processing the object-side surface of a specific example of a spectacle lens using pulsed laser light with a wavelength of 355 nm and a pulse width of 10 picoseconds or more and less than 20 picoseconds. [Figure 6B] FIG. 6B is a photograph showing the results of processing the eyeball side surface of one specific example of a spectacle lens using pulsed laser light with a wavelength of 355 nm and a pulse width of 10 picoseconds or more and less than 20 picoseconds. [Figure 6C] FIG. 6C shows the reflection characteristics (simulation data) of antireflection coating (1) (described later) and antireflection coating (2) (described later) of a specific example eyeglass lens, with the vertical axis representing reflectance (%) and the horizontal axis representing wavelength (nm). [Figure 7] FIG. 7 shows the results of determining a specific range of laser power that provides stable processing conditions when processing the antireflection coating (1) and the antireflection coating (2) in the same manner as in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0025] <Gist of this embodiment> Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0026] The spectacle lens according to this embodiment has, as optical surfaces, an object-side surface and an eyeball-side surface. The "object-side surface" is the surface that is located on the object side when spectacles equipped with the spectacle lens are worn by a wearer. The "eyeball-side surface" is the opposite, that is, the surface that faces the eyeball when spectacles equipped with the spectacle lenses are worn by a wearer. Generally, the surface on the object side is convex and the surface on the eyeball side is concave, that is, spectacle lenses are meniscus lenses. This also applies to eyeglass lenses (processed lenses) after edging, in which the periphery is cut to fit the shape of the eyeglass frame.

[0027] In other words, in this embodiment, when an eyeglass lens has an anti-reflection coating on both the object-side and eyeball-side surfaces, and the anti-reflection coating has different reflectances for light of wavelengths within a predetermined range on the object-side surface and the eyeball-side surface, this difference is utilized. Then, an optical surface with a lower reflectance for the wavelength of the applied laser is selected, and laser processing is performed from the optical surface side.

[0028] For example, when laser processing is performed using a wavelength in the ultraviolet region, processing is performed on a surface on which an anti-reflection film with a relatively low reflectance for ultraviolet wavelengths is formed. Alternatively, in a method for manufacturing an eyeglass lens in which a desired process is performed by irradiating one surface of an eyeglass lens, the object-side surface and the eyeball-side surface of which are provided with different anti-reflection films, with a laser to perform marking (or patterning, collectively referred to as "marking" in this application), the method may include selecting one of the object-side surface and the eyeball-side surface that has a relatively low reflectance to light in a predetermined wavelength range, and applying laser light having a wavelength within the predetermined range to the selected surface to perform laser irradiation.

[0029] The wavelength range applied to the laser irradiation is not particularly limited, but may be, for example, an ultraviolet wavelength in the range of 200 to 400 nm. Specifically, it may be 355 nm (THG) or 266 nm (FHG), which will be described later.

[0030] Furthermore, the reflectance of the lens surface for any laser light within the above wavelength range will differ depending on the optical properties of the antireflection film formed on the lens surface. For example, by forming different antireflection films on both surfaces as described above, the reflectance of one surface (e.g., the surface on the object side) minus the reflectance of the other surface (e.g., the surface on the eyeball side) for the wavelength applied to laser irradiation may be 10% or more (or 15% or more, or 20% or more).

[0031] The wavelength-dependent reflectance characteristics of the antireflection film can be adjusted by changing the composition and film thickness of each layer (high refractive index layer and low refractive index layer, described later) of the multilayer structure that makes up the antireflection film.

[0032] For example, when the applicable wavelength used for laser irradiation is in the ultraviolet range and the reflectance of the surface on the eyeball side for that wavelength is relatively low compared to that on the object side, laser processing can be performed on the surface on the eyeball side. The laser processing may be removal processing from the outermost surface using ablation, which will be described in detail below.

[0033] Furthermore, the spectacle lens according to this embodiment is a spectacle lens in which the reflectance of light with wavelengths of at least 330 to 400 nm is lower on the eyeball-side surface than on the object-side surface of the spectacle lens, and marking is performed on the eyeball-side surface using a laser with a wavelength within the above wavelength range.

[0034] By applying the manufacturing method for eyeglass lenses according to this embodiment, it is possible to provide eyeglass lenses in which different anti-reflection films are provided on the object-side surface and the eyeball-side surface, and the surface with a relatively low reflectance for light of a specified wavelength is decorated by laser marking.

[0035] Alternatively, when laser processing is performed using a wavelength in the infrared region, processing is performed on a surface on which an anti-reflection film with a relatively low reflectance at infrared wavelengths is formed. For example, the wavelength applied to laser irradiation can be a wavelength in the infrared region in the range of 800 to 1100 nm. Specifically, a 1064 nm laser can be used.

[0036] The spectacle lens may have a lower reflectance of light with wavelengths of at least 800 to 1100 nm on the surface facing the eyeball than on the surface facing the object, and may have markings on the surface facing the eyeball using a laser with a wavelength within the above wavelength range.

[0037] <One specific example of this embodiment> FIG. 1 is a plan view showing an example of processing of a spectacle lens according to this embodiment.

[0038] In this embodiment, a spectacle lens 1 having a circular shape in plan view (for example, an outer diameter of 60 to 80 mm) is subjected to edging (frame cutting) to cut the lens outer shape to fit the frame shape 2 of the spectacle frame worn by the wearer.

[0039] In this embodiment, prior to edging, marking may be performed within the area corresponding to the inside of the outline of the frame shape.

[0040] In this embodiment, a case will be exemplified in which a decorative pattern 3 representing a logo, house mark, letters, symbols, designs, etc. is marked on the optical surface so as to be positioned within the lens area after frame cutting.

[0041] Marking can be performed, for example, using laser irradiation processing, which allows precise control of the irradiation position based on digital data, but it is undesirable for the marking to result in a deterioration in lens quality or function.

[0042] Therefore, in this embodiment, the decorative pattern 3 is marked by the following processing procedure.

[0043] (1) Manufacturing method of eyeglass lenses Here, the processing procedure for the eyeglass lens including the marking of the decorative pattern, that is, the procedure for the method for manufacturing the eyeglass lens according to this embodiment will be specifically described.

[0044] FIG. 2 is a flow chart showing an example of the procedure of the method for manufacturing a spectacle lens according to this embodiment.

[0045] In manufacturing eyeglass lenses, first, a lens substrate, which is an optical base material, is prepared, and then the lens substrate is polished according to the prescription information of the eyeglass wearer to obtain a lens shape with predetermined optical performance, and dyed as necessary (step 101; hereinafter, step will be abbreviated as "S").

[0046] The lens substrate is made of a resin material with a refractive index (nD) of approximately 1.50 to 1.74, for example.

[0047] Specifically, examples of the resin material include allyl diglycol carbonate, urethane resin, polycarbonate, thiourethane resin, and episulfide resin.

[0048] However, instead of these resin materials, the lens may be made of other resin materials that can provide the desired refractive index, or may be made of inorganic glass.

[0049] The lens substrate also has optical surfaces for forming a predetermined lens shape on both the object side surface and the eyeball side surface.

[0050] The predetermined lens shape may be a single-focus lens, a multifocal lens, a progressive power lens, or the like, but in any case, each optical surface is formed by a curved surface specified based on the prescription information of the eyeglass wearer.

[0051] The optical surface is formed by, for example, a polishing process, but may also be a cast (molded) product that does not require polishing.

[0052] The polishing and dyeing of the lens substrate may be performed using known techniques, and detailed description thereof will be omitted here.

[0053] Thereafter, a hard coat film (HC film) is formed on at least one optical surface, preferably on both optical surfaces of the lens substrate (S102).

[0054] The HC film is made of a curable material containing, for example, a silicon compound, and is a film formed to a thickness of about 3 μm to 4 μm.

[0055] The refractive index (nD) of the HC film is close to the refractive index of the material of the lens substrate, for example, about 1.49 to 1.74, and the film configuration is selected depending on the material of the lens substrate.

[0056] Such an HC film coating can improve the durability of the eyeglass lens.

[0057] The HC film may be formed by, for example, a dipping method using a solution in which a curable material containing a silicon compound is dissolved.

[0058] After the HC film is formed, an anti-reflection film (AR film) is subsequently formed so as to overlap the HC film (S103).

[0059] The AR coating has a multi-layer structure in which films with different refractive indices are stacked, and prevents light reflection through interference.

[0060] Specifically, the AR film has a multi-layer structure in which a low refractive index layer and a high refractive index layer are stacked.

[0061] The low refractive index layer is made of, for example, silicon dioxide (SiO2) with a refractive index of about 1.43 to 1.47.

[0062] The high refractive index layer is made of a material having a higher refractive index than the low refractive index layer, such as zirconium oxide (ZrO2), tin oxide (SnO2), niobium oxide (Nb2O5), tantalum oxide (Ta2O5), titanium oxide (TiO2), yttrium oxide (Y2O3), aluminum oxide (Al2O3), or a mixture thereof (e.g., indium tin oxide (ITO)).

[0063] Among these, the high refractive index layer containing Sn and O functions as a reactive layer because it has a higher reactivity to the ultrashort pulse laser (described later) than other layers. Specifically, the above-mentioned SnO2 and ITO fall into this category.

[0064] In this specification, the term "reactive layer" refers to a layer that has low excitation energy when irradiated with a laser. In one embodiment of the present invention, the layer is irradiated with an ultrashort pulse laser.

[0065] The SnO layer, which can be a reactive layer, has extremely low excitation energy due to multiphoton absorption (e.g., two-photon absorption), making it highly reactive. The same is true for the ITO layer, and the ITO layer can also be a reactive layer in this specification.

[0066] As a result, in one embodiment of the present invention, at least a portion of the SnO2 layer (or ITO layer) sublimes or evaporates, and disappears from the irradiated area together with the overlying SiO2 layer.

[0067] In one embodiment of the present invention, the reactive layer having a higher reactivity than other layers included in the multilayer structure refers to a SnO2 layer or an ITO layer, and may be set as the most reactive layer compared to other layers included in the multilayer structure.

[0068] The outermost layer of the multi-layered AR film is configured to be a low refractive index layer (for example, an SiO2 layer).

[0069] As described above, only the portion of the surface layer of the multilayer structure that has been irradiated with laser is removed, forming a decorative pattern that represents desired characters, symbols, designs, etc. When illumination light or sunlight is incident on such a decorative pattern, the reflected light from that portion has different reflection characteristics from the other portions (other than the portion where part of the multilayer structure has been removed).

[0070] Therefore, when such decorated lenses are worn as spectacles, the decorated portions are perceived by others as having a different brightness and color tone from the remaining portions.

[0071] In addition, it is preferable that the bottom layer (on the substrate side) of the multilayer structure is also a low refractive index layer (e.g., an SiO2 layer), which makes it easier to see the pattern created by the laser processing from the side opposite the laser-processed surface, out of the two surfaces of the eyeglass lens.

[0072] Furthermore, depending on the materials selected for the outermost and innermost layers, the front and back of the lens may have different visibility (different color tones or brightness).

[0073] The above-mentioned films constituting the AR film may be formed by, for example, applying ion-assisted deposition.

[0074] A water-repellent film may be formed on the low refractive index layer, which is the outermost layer of the AR film. The water-repellent film may also be called an anti-fouling film.

[0075] The water-repellent film may be formed before or after the marking according to this embodiment.

[0076] The water-repellent film is a film that gives water repellency to the surface, and can be formed by applying a solution of a fluorine-based compound such as metaxylene hexafluoride.

[0077] The water-repellent film may be formed by applying, for example, ion-assisted deposition, in the same manner as in the case of the AR film.

[0078] In addition, other functional layers may be formed on the AR film. Such functional layers may or may not contain metal components, as long as the precise processing effect of laser irradiation is achieved. Furthermore, such functional layers may be uniform films or may be scattered on the surface.

[0079] Through the above-described film formation process, a thin film with a laminated structure as shown in FIG. 3 is formed on the optical surface of the lens substrate.

[0080] FIG. 3 is a cross-sectional side view showing an example of a laminated structure of thin films according to this embodiment.

[0081] The laminated structure shown in the figure is configured by laminating an HC film 12, an AR film 13, and a water-repellent film 14 in this order on the optical surface of a lens substrate 11.

[0082] The AR film 13 has a multilayer structure in which a low-refractive index SiO2 layer 13a is laminated with high-refractive index SnO2 layer 13b and ZrO2 layer 13c, with the SiO2 layer 13a being the outermost layer (i.e., the surface layer on the water-repellent film 14 side). Here, the SnO2 layer is both a high-refractive index layer and a reactive layer.

[0083] After the thin film is formed, as shown in FIG. 2, the eyeglass lens on which the thin film is formed is subjected to frame cutting processing and decorative pattern marking.

[0084] First, marking is performed on the eyeglass lens after the thin film has been formed. If the decorative processing is performed after the frame cutting (S104: After Cutting), first, one optical surface of the eyeglass lens to be processed (specifically, the optical surface that will not be subjected to the decorative processing described later) is attached to a dedicated jig (jig blocking) (S105). Then, the blocked eyeglass lens is set in an edge processing machine, and edge processing (frame cutting) is performed on the eyeglass lens, and the outer shape of the eyeglass lens is cut into the frame shape (S106). Jig blocking and frame cutting can be performed using known techniques, so detailed explanations will be omitted here.

[0085] Next, while the lens is still blocked by the jig, the lens height of the processing area (i.e., the three-dimensional shape of the processing area on the processing surface) is measured for the processing surface of the eyeglass lens to be processed (specifically, the optical surface on the unblocked side) (S107). The measurement method is not particularly limited, but it is possible to use, for example, a non-contact or contact three-dimensional measuring machine. The processing area is an area that includes the laser scan area described below.

[0086] After measuring the lens height in the processing area, laser processing is performed. That is, laser processing is performed by irradiating while performing raster scanning, which moves the laser light, based on pattern data prepared in advance (S108). More preferably, the scan head can be simultaneously controlled in the height direction based on the three-dimensional shape data obtained above, and focus control (or defocus control) of the laser irradiation can be performed according to the curved surface of the lens optical surface. Vector scanning may be used instead of raster scanning. This results in markings being made in the processing area on the processing surface of the eyeglass lens.

[0087] After the decorative pattern is marked, the eyeglass lens is removed from the dedicated jig (Jig Deblocking) (S109), and the removed eyeglass lens is cleaned to remove any residue from the marking process and any adhering matter (foreign matter) (S110).Then, a final lens appearance inspection (S111) is performed, and the manufacturing of the eyeglass lens is completed.

[0088] On the other hand, for example, if the frame is cut after the decorative processing (S104: before cutting), first, the lens height of the processing area on the processing surface of the eyeglass lens to be processed (i.e., the three-dimensional shape of the processing area on the processing surface) is measured (S112). The measurement method is the same as that in the case where the decorative processing is performed after the frame cutting described above.

[0089] After measuring the lens height in the processing area, laser processing is performed by irradiating the processing area with laser light. The processing method can be the same as the above-mentioned case of performing decorative processing after frame cutting.

[0090] As a result, the decorative pattern is marked in the processing area of ​​the processing surface of the eyeglass lens. Details of the laser processing for marking the decorative pattern will be described later.

[0091] After the decorative pattern is marked, the spectacle lens is subjected to frame cutting processing.

[0092] In the frame cutting process, first, one optical surface of the eyeglass lens to be processed is attached to a dedicated jig to perform jig blocking (S114), and then the blocked eyeglass lens is set in an edge processing machine to perform edge processing (frame cutting) on ​​the eyeglass lens, and the outer shape of the eyeglass lens is cut into the frame shape (S115).

[0093] After the frame cutting process, jig deblocking is performed to remove the eyeglass lenses from the dedicated jig (S116), and the removed eyeglass lenses are cleaned to remove any remaining material or adhering matter (foreign matter) from the processing (S117).Then, a final lens appearance inspection (S118) is performed, and the manufacturing of the eyeglass lenses is completed.

[0094] (2) Details of laser processing Next, the laser processing used to mark the decorative pattern will be described in more detail.

[0095] In this embodiment, the AR film 13 covering the optical surface of the lens substrate 11 is irradiated with laser light, thereby locally and at least partially removing predetermined layers including the SiO2 layer 13a, which is the outermost layer of the AR film 13, thereby marking the decorative pattern.

[0096] Specifically, when the laser beam passes through the outermost SiO2 layer and reaches the underlying SnO2 layer, the SnO2 layer is at least partially sublimated or evaporated by the energy of the irradiation, and disappears from the irradiated area together with the SiO2 layer on the upper side. In other words, the laser processing by irradiating the laser beam locally removes a predetermined layer including the outermost SiO2 layer 13a.

[0097] At this time, a visible decorative pattern is marked at the irradiated area due to the difference in reflection characteristics between the irradiated area and the unremoved area through a removal process that exposes the underlying high refractive index layer, for example, the ZrO2 layer 13c.

[0098] The SnO2 layer 13b can be formed to a small thickness (for example, 3 to 20 nm, more preferably 3 to 10 nm). In this embodiment, the SnO2 layer 13b was formed to a thickness of 5 nm.

[0099] In the above, SnO2 functions as a reactive layer that is most reactive to laser irradiation. This reactive layer preferably contains Sn and O, and in addition to SnO2, ITO can also be used.

[0100] In the above, SnO2 is removed by sublimation or evaporation, and the ZrO2 layer underneath as a high refractive index layer is exposed at the irradiated area, but the reaction layer does not necessarily have to be completely removed, and a portion of it may remain at the irradiated area.

[0101] For example, the reaction layer may be at least partially removed in the thickness direction of the layer by laser irradiation.

[0102] As another example of partial removal, the laser irradiation may leave a portion of the reaction layer at the laser irradiated location when viewed from the laser irradiation direction (plan view) as well as in the thickness direction of the layer. In the example of this paragraph, it is acceptable for ZrO2 to be only partially exposed. This is because, like ZrO2, SnO2 (or ITO) is a high refractive index material, and even if some SnO2 remains when viewed planarly, this does not cause a problem with visibility.

[0103] Therefore, it is sufficient that the high refractive index layer below the reaction layer or the partially remaining reaction layer is exposed.

[0104] The phenomenon that occurs during laser irradiation is thought to be as follows: The reactive layer (SnO2, ITO, etc.) is preferably a conductive layer that has higher conductivity than the other layers included in the laminated structure.

[0105] According to the investigation, the reaction layer made of SnO2 has a smaller energy corresponding to the band gap where excitation occurs when irradiated with laser under the conditions described below than the SiO2 on the upper layer side (outermost surface side) and the ZrO2 layer on the lower layer side. Therefore, compared to the adjacent layers on the upper and lower layers, it is most likely to disappear due to sublimation or evaporation.

[0106] At this time, a phenomenon known as multi-photon absorption (e.g., two-photon absorption) is thought to occur, enabling processing with extremely high energy efficiency. The fact that SnO2 is a conductive layer is thought to be an advantage in this case.

[0107] Regarding the concern that the ZrO2 on the lower layer may be damaged by evaporation or dissolution due to the irradiation energy after the SnO2 has disappeared, it is possible to take advantage of the delay before such damage occurs by controlling the irradiation conditions, thereby substantially removing only the reaction layer and the layers above it. Furthermore, it has been found that selecting an ultrashort pulse laser, which will be described later, is advantageous for such precise processing control.

[0108] Here, a laser processing device used for laser processing will be briefly described.

[0109] FIG. 4 is an explanatory diagram showing an example of the schematic configuration of a laser processing device used in the method for manufacturing eyeglass lenses according to this embodiment.

[0110] As shown in FIG. 4A, the laser processing apparatus used in this embodiment includes a laser light source unit 21, an AOM (Acousto Optics Modulator) system unit 22, a beam shaper unit 23, a galvanometer scanner unit 24, and an optical system 25, and is configured to irradiate the AR film 13 with laser light via these units 21 to 25.

[0111] The laser light source unit 21 emits laser light used in laser processing, and is configured to emit an ultrashort pulse laser.

[0112] In this embodiment, the lower limit of the pulse width of the ultrashort pulse laser is not particularly limited as long as it exceeds 0 femtoseconds, but a pulse width of 0.01 picoseconds (10 femtoseconds) or more is preferable, and using a pulse width of 0.1 picoseconds or more (including 1 picosecond or more) is advantageous in terms of equipment maintenance and cost, and is more suitable for commercial use.

[0113] For example, a pulse width of 0.01 picoseconds (10 femtoseconds) or more and less than 100 picoseconds, preferably a pulse width of 0.01 picoseconds or more and less than 50 picoseconds, and more preferably a pulse width of 0.01 picoseconds or more and less than 15 picoseconds, can also be used.

[0114] Furthermore, for example, a pulse width of 0.1 picoseconds or more and less than 100 picoseconds, preferably a pulse width of 0.1 picoseconds or more and less than 50 picoseconds, and more preferably a pulse width of 0.1 picoseconds or more and less than 15 picoseconds can be used.

[0115] Also, a pulse width of 0.01 picoseconds or more and less than 1 picosecond (or less than 0.1 picoseconds) can be used.

[0116] The wavelength of the ultrashort pulse laser can be, for example, 266 nm FHG (Fourth Harmonic Generation) in the ultraviolet range, or 355 nm THG (Third Harmonic Generation), or a fundamental wavelength of 1064 nm in the infrared range. The irradiation beam diameter can be selected according to the desired processing design.

[0117] In order to process fine designs with high resolution, it is effective to narrow the beam diameter, and in this case, shorter wavelengths are more advantageous, so of the wavelengths mentioned above, 355 nm is more preferable. Alternatively, 266 nm FHG (Fourth Harmonic Generation) is also suitable.

[0118] The pulse energy of the ultrashort pulse laser is, for example, 0.1 μJ to 30 μJ (maximum approximately 60 μJ) at 50 kHz. The beam diameter of the ultrashort pulse laser is, for example, 10 μm to 100 μm. The processing diameter can be, for example, 10 to 50 μm.

[0119] According to the inventor's investigation, the following was found regarding the laser irradiation conditions.

[0120] (1) When the pulse width of an ultrashort pulse laser is less than 0.1 picoseconds, good processing can be achieved with any wavelength between 266 and 1064 nm. Shorter wavelengths are more advantageous for microfabrication. However, they are costly in terms of maintenance and management, including the initial investment and running costs of the equipment. (2) When the pulse width of the ultrashort pulse laser is 0.1 picoseconds or more and less than 1 picosecond, good processing can be performed even with a wavelength of 266 to 1064 nm. A shorter wavelength is more advantageous for fine processing. (3) When the pulse width of the ultrashort pulse laser is 1 picosecond or more and less than 100 picoseconds, good processing can be achieved with any wavelength between 266 and 1064 nm. Shorter wavelengths are more advantageous for microfabrication, and are favorable in terms of equipment maintenance, cost, and stability of production conditions. (4) When the pulse width of an ultrashort pulse laser is greater than 100 picoseconds and less than 1 nanosecond, non-uniform processing stability occurs depending on the wavelength. For example, when using a short wavelength of 266 nm, damage to the underlying layer is likely to occur along with the reaction of SnO2. Even with a 355 nm laser, even a slight change in irradiation conditions can cause processing uniformity to be lost, and it is not possible to prevent the removal processing from reaching the layer below the SnO2. (5) When the pulse width of the ultrashort pulse laser is 1 nanosecond or longer, it is not possible to selectively remove SnO2 and the layer on the surface thereof.

[0121] In the cases of (4) and (5) above, the visibility of the processed pattern is affected. For example, in the case of eyeglass lenses, there is a risk of interference with the wearer's field of vision. Furthermore, when observing the formed decorative pattern, unless the lighting conditions are such that the pattern is clearly visible to the observer, the observer may perceive the lens as having foreign matter or dirt, rather than a clear lens, which can easily result in an imperfect visibility state.

[0122] In order to prevent the above-mentioned inconveniences, it is essential that the removal processing using an ultrashort pulse laser is uniform in terms of the processing diameter and processing depth. To achieve this, it is considered useful to apply a predetermined ultrashort pulse width to control and utilize the duration of the energy emitted by irradiation and the delay in ablation of the underlying material.

[0123] As long as such an ultrashort pulse laser can be emitted, the specific configuration of the laser light source unit 21 or the combination of wavelength and pulse width is not particularly limited.

[0124] The AOM system unit 22 suppresses excessive irradiation of laser light, which can cause uneven processing during laser processing, by canceling the beam output of laser light immediately after the galvano scanner unit 24 starts operating and just before its operation ends.

[0125] The beam shaper unit 23 converts the Gaussian energy distribution of the laser light from the laser light source unit 21 into a top-hat energy distribution, thereby enabling laser processing using laser light with a uniform energy distribution. In particular, applying a top-hat distribution enables stable and uniform processing when attempting to form a processing region of a predetermined area by partially overlapping multiple beam spots. This is because localized excess energy addition caused by spot overlapping is suppressed.

[0126] The galvanometer scanner unit 24 moves the irradiation position of the laser light from the laser light source unit 21 in two or three dimensions, thereby enabling scanning with the laser light, thereby enabling marking of the desired pattern by laser processing. The scanning range 4 of the laser light by the galvano scanner unit 24 (i.e., the maximum laser processing area) is set to a size and shape that can completely encompass the outer shape of the eyeglass lens to be processed (see Figure 1).

[0127] The optical system 25 is composed of a combination of optical lenses such as telecentric lenses and mirrors, and guides the laser light from the laser light source unit 21 so that the laser light reaches the area of ​​the eyeglass lens to be processed.

[0128] Furthermore, the laser processing device used in this embodiment is preferably configured so that the irradiation of the laser light (i.e., ultrashort pulse laser) onto the AR film 13 via the optical system 25 or the like can be focused on the AR film, and can also be defocused on the AR film, as shown in FIG. 4B.

[0129] The defocus setting refers to a setting in which the focal position F of the irradiated laser beam is set a predetermined defocus distance away from the surface of the AR film 13, which is the area to be processed by the laser beam. Irradiating the laser beam with such a defocus setting allows the beam energy to be dispersed on the surface of the AR film 13 irradiated with the laser beam, thereby enabling uniform film removal processing. This is particularly useful when the height of the irradiated area may vary due to the surface shape of the AR film 13. However, the defocus setting is not necessarily required. For example, the laser beam may be irradiated with a focus setting in which the focal position F coincides with the surface of the AR film 13, or with an in-focus setting in which the focal position F is spaced apart in the opposite direction from the defocus setting.

[0130] Next, a laser processing procedure performed using the laser processing device configured as above will be described.

[0131] In laser processing, first, the eyeglass lens to be processed is set in the laser processing device. At this time, the eyeglass lens is set so that the optical surface of the eyeglass lens, more specifically, the surface of the AR film 13 on the optical surface, becomes the surface to be processed. The optical surface to be processed may be either the surface on the object side or the surface on the eyeball side, but here, for example, the surface on the eyeball side is used as the surface to be processed.

[0132] After the eyeglass lens is set, the laser light source unit 21 and the galvano scanner unit 24 are operated based on the pattern data prepared in advance (i.e., pattern data with a predetermined resolution created based on the desired decorative pattern). As a result, the processing area on the processing surface of the eyeglass lens is irradiated with an ultrashort pulse laser in a pattern shape corresponding to the decorative pattern.

[0133] When the ultrashort pulse laser is irradiated, the ultrashort pulse laser passes through the water-repellent film 14 on the surface of the eyeglass lens to be processed and reaches the AR film 13 on the surface to be processed. When the ultrashort pulse laser reaches the AR film 13, non-thermal processing occurs due to the use of the ultrashort pulse laser.

[0134] This type of ablation processing is a technology that enables highly energy-efficient processing by utilizing the multiphoton absorption phenomenon of an ultrashort pulse laser. More specifically, it is a removal process in which the irradiated area of ​​the laser beam is instantaneously melted, evaporated, or sublimated and scattered while minimizing the thermal effects around the processing area. This type of non-heating processing allows highly reactive materials to be instantly removed at the irradiated area, resulting in less thermal effects around the processing area and reduced thermal damage (such as deformation due to heat).

[0135] The laser processing according to this embodiment can be ablation processing, which is a non-thermal processing. Such processing can cause a multiphoton absorption process (e.g., a two-photon absorption process) that brings about the multiphoton absorption phenomenon mentioned above. Therefore, multiphoton absorption can be used to efficiently and effectively process materials that are relatively transparent (highly transmittant) to lasers. In this case, the applicable laser wavelength range is wide, and the wavelength of the laser light can be 266 nm (FHG), 355 nm (THG), 532 nm (SHG), or 1064 nm. According to this embodiment, particularly significant effects can be obtained when the ultraviolet region (266 nm, 355 nm) or the infrared region (1064 nm) is used as the applicable wavelength for irradiation.

[0136] As mentioned above, picosecond lasers and femtosecond lasers with short pulse widths are advantageous for inducing the multiphoton absorption. Specific values ​​include pulse widths of less than 100 picoseconds, preferably less than 50 picoseconds, and more preferably less than 1 picosecond (i.e., femtoseconds). While there is no particular lower limit, a pulse width of 10 femtoseconds or more is desirable.

[0137] When non-thermal processing is performed by irradiating the ultrashort pulse laser, the laser penetrates the SiO2 of the multilayer structure of the AR film 13 and reaches the reactive layer (SnO2 in this embodiment). The reactive layer instantly reacts and sublimes / evaporates, removing the SiO2 layer 13a, which is the outermost layer. In this way, only specific layers, including the outermost layer of the anti-reflection film, are partially removed in a pattern corresponding to the decorative pattern. This also removes the corresponding portion of the water-repellent film 14. As a result, the ZrO2 layer 13c located below the SnO2 layer 13b is exposed at the irradiated location.

[0138] By carrying out the above-described laser processing, predetermined layers including the SiO2 layer 13a, which is the outermost layer of the AR film 13, are partially removed (removed portions are formed), exposing the ZrO2 layer 13c as a high refractive index layer, thereby marking the decorative pattern on the processed surface of the eyeglass lens. Note that even if part of the reaction layer remains, the remaining reaction layer is a high refractive index layer, so the visibility of the decorative pattern is not impaired.

[0139] As described above, the irradiated portion where the predetermined laser irradiation is performed is partially processed within the surface to be processed.

[0140] (3) Composition of eyeglass lenses Next, the configuration of the eyeglass lens obtained by the manufacturing method with the above-described procedure, that is, the configuration of the eyeglass lens according to this embodiment, will be specifically described.

[0141] Fig. 5A is an explanatory diagram showing an example of the configuration of the main parts of a spectacle lens according to this embodiment. Fig. 5B shows a specific example of the results of electron microscopic observation of a cross section of the AR film 13. The example shows an enlarged view of parts A and B in Fig. 5A, showing electron microscope images of the laser scan area 16 and the non-processed area 15.

[0142] 5A, the eyeglass lens according to this embodiment is configured by laminating an HC film 12, an AR film 13, and a water-repellent film 14 in this order on the optical surface of a lens substrate 11. The AR film 13 has a multilayer structure in which a low-refractive-index layer SiO2 layer 13a and high-refractive-index layers SnO2 layer 13b and ZrO2 layer 13c are laminated, and predetermined layers including the outermost SiO2 layer 13a of the multilayer structure (specifically, the SnO2 layer as a reaction layer and layers further on the surface thereof) are partially removed to expose the high-refractive-index layer ZrO2 layer 13c. In other words, the eyeglass lens of this embodiment is configured to include an unprocessed area 15 in which the optical surface of the lens substrate 11 is covered with an HC film 12, an AR film 13, and a water-repellent film 14, and a laser scan area (patterned area) 16 in which the outermost SiO2 layer 13a of the AR film 13, the SnO2 layer 13b directly below it, and the water-repellent film 14 are partially removed, exposing the high-refractive index layer, ZrO2 layer 13cb.

[0143] One of the non-processed area 15 and the laser scan area 16 is covered with an SiO2 layer 13a, while the other has an exposed ZrO2 layer 13c (or, if a portion of the reaction layer remains, the reaction layer, which is a high-refractive layer). Therefore, the presence or absence of the SiO2 layer 13a results in different light reflectances in the respective areas. Therefore, when the spectacle lens is viewed in a state where illumination light is irradiated, the pattern shape formed by the laser scan area 16 becomes visible. In other words, if the laser scan area 16 is formed in a pattern shape corresponding to the decorative pattern, the decorative pattern can be visually recognized. In this way, the removed portions of a predetermined layer of the AR film 13 can be used to form the decorative pattern.

[0144] The laser scan area 16 constituting the decorative pattern is formed by removing the SiO layer 13a, which is the outermost layer of the AR film 13, and the SnO layer 13b, which is the layer immediately below it. In other words, the removal target is limited to a specific layer containing SnO, which is the reactive layer. This prevents peeling of each layer of the multilayer structure constituting the AR film 13 due to the formation of the laser scan area 16.

[0145] As described above, the removal of the SiO2 layer 13a, which is the outermost layer of the AR film 13, can be achieved by non-thermal processing using ultrashort pulse laser irradiation. This non-thermal processing minimizes the thermal impact on the area around the processing site, thereby preventing thermal damage. Furthermore, applying the specified pulse width allows for stable processing while minimizing damage to layers below the reaction layer. This exposes the ZrO2 layer 13c, which serves as a high-refractive index layer, but prevents damage to the exposed surface of the ZrO2 layer 13c.

[0146] If damage to the exposed surface of the ZrO2 layer 13c can be suppressed, the thickness of the ZrO2 layer 13c can also be suppressed from being reduced due to the removal processing of the SiO2 layer 13a. The thicknesses of the SiO2 layer 13a, ZrO2 layer 13c, etc. can be determined by obtaining an electron microscope image of the cross section of the AR film 13 and analyzing the obtained image.

[0147] FIG. 5B shows a specific example of the cross section of the AR film 13 observed with an electron microscope.

[0148] The example shown in the figure is an enlarged view of parts A and B in Figure 5A, showing electron microscope images of the laser scan area 16 and the non-processed area 15. In the non-processed area 15, an SiO2 layer 13a, an SnO2 layer 13b, and a ZrO2 layer 13c are stacked, but the SnO2 layer 13b is difficult to recognize in the image because it is thin (e.g., about 5 nm). On the other hand, in the laser scan area 16, the SnO2 layer 13b and the SiO2 on the surface side thereof have been removed, exposing the ZrO2 layer 13c.

[0149] The electron microscope image in the figure shows that, in the ZrO2 layer 13c that is exposed by removing the SnO2 and the layers on the surface thereof, there is no significant difference between the thickness t1 of the laser scan region 16 and the thickness t2 of the non-processed region 15. More specifically, the ratio t1 / t2 of the thickness t1 of the removed portion to the thickness t2 of the non-removed portion is set to, for example, within the range of 0.90 to 1.00, preferably 0.95 to 1.00, and more preferably 0.99 to 1.00.

[0150] Thus, the exposed high-refractive index layer, the ZrO2 layer 13c, does not experience any reduction in thickness due to the removal process, or if any reduction occurs, the amount of reduction is kept extremely small. This is because the laser scan region 16 is formed by non-thermal processing using ultrashort pulse laser irradiation, and the underlying ZrO2 layer 13c is not damaged. This means that if the thickness ratio t1 / t2 of the exposed ZrO2 layer 13c is within the above-mentioned range, the laser scan region 16 is formed without damaging the ZrO2 layer 13c, and it can be assumed that the laser scan region 16 was formed using non-thermal processing using an ultrashort pulse laser.

[0151] The reason why the ZrO2 layer 13 is not damaged is because the reactivity of the reactive layer (here, the SnO2 layer) with the ultrashort pulse laser is higher than that of ZrO2. This difference in reactivity can be significantly achieved by applying an ultrashort pulse laser with a predetermined pulse width, as will be described later.

[0152] Furthermore, since the thickness of the ZrO2 layer is 10 times or more, preferably 15 times or more, the thickness of the SnO2 layer, even if the ZrO2 layer is slightly reduced after the SnO2 layer has disappeared, there is no risk of film peeling or any effect on the visibility of the decorative pattern.

[0153] Furthermore, the melting point of SnO2 is about 1127°C, which is lower than that of SiO2 on the upper layer and that of ZrO2 on the lower layer, and this is thought to be related to the ease of ablation control.

[0154] With the eyeglass lens configured as described above, even if a decorative pattern is marked, peeling of the layers constituting the multilayer AR film 13 can be suppressed, and the exposed ZrO2 layer 13c is not damaged. Therefore, even when applied to eyeglass lens products, it is possible to mark a decorative pattern on the eyeglass lens without causing a decrease in the quality of the product.

[0155] (4) Effects of this embodiment First, this embodiment provides the following advantageous effects.

[0156] In this embodiment, even if an eyeglass lens has anti-reflection coatings on both sides, if the reflectance of the object-side surface and the eyeball-side surface differs for light of wavelengths within a predetermined range, this fact is utilized, and laser processing is performed by applying wavelengths within the predetermined range to the optical surface with the lower reflectance.

[0157] The method for manufacturing a spectacle lens according to this embodiment allows for efficient and precise decoration under stable conditions even for spectacle lenses in which anti-reflection coatings are provided on both the object-side surface and the eyeball-side surface.

[0158] More specifically, one or more of the following effects can be obtained.

[0159] (a) In this embodiment, the AR film 13, which is one of the thin films that coat the optical surface of the lens substrate 11, is partially removed from the reaction layer (SnO2 in the above embodiment) of the AR film 13 and the layer on the surface thereof, thereby exposing the ZrO2 layer 13c, which is a high refractive index layer, and thereby marking a decorative pattern on the eyeglass lens.

[0160] (b) In this embodiment, non-thermal processing is performed by irradiating an ultrashort pulse laser to partially remove the reaction layer (SnO in the above embodiment) of the AR coating 13 and the layers above it, thereby exposing the high-refractive-index ZrO layer 13c, thereby marking a decorative pattern on the eyeglass lens. This non-thermal processing relies on the pulse width effect rather than the absorption energy effect of the laser light, making it possible to selectively and uniformly remove only specific layers, including the SiO layer 13a, which is the outermost layer of the AR coating 13. Furthermore, because it is non-thermal processing, thermal damage around the processing area can be suppressed, thereby suppressing damage to the exposed surface of the ZrO layer 13c below the reaction layer.

[0161] (c) As described above, in this embodiment, a decorative pattern is marked on a spectacle lens by removing predetermined layers, including the outermost layer of the AR film 13, using an ultrashort pulse laser to expose the high refractive index layer. Therefore, this embodiment can prevent peeling of the layers of the AR film 13 and also prevents damage to the exposed ZrO2 layer 13c. Therefore, even when applied to spectacle lens products, it is possible to mark a decorative pattern on a spectacle lens without degrading the quality of the product.

[0162] (d) In this embodiment, the pulse width of the ultrashort pulse laser may be greater than 0 femtoseconds, but is preferably greater than or equal to 0.01 picoseconds (10 femtoseconds) and less than 100 picoseconds. Using a pulse width of 0.1 picoseconds or greater (including 1 picosecond or greater) is advantageous in terms of device maintenance and cost, and is more suitable for commercial use. More specifically, the laser irradiation conditions have the following advantages depending on the pulse width: (1) When the pulse width of an ultrashort pulse laser is less than 0.1 picoseconds, it can perform good processing at both ultraviolet and infrared wavelengths. Shorter wavelengths are more advantageous for microfabrication. However, they impose a large burden on production in terms of equipment maintenance and costs. (2) When the pulse width of the ultrashort pulse laser is 0.1 picoseconds or more and less than 1 picosecond, good processing can be performed at any of the wavelengths mentioned above. A shorter wavelength is more advantageous for fine processing. (3) When the pulse width of the ultrashort pulse laser is 1 picosecond or more and less than 100 picoseconds, good processing can be performed with any of the above wavelengths. Shorter wavelengths are more advantageous for microfabrication. They are preferable in terms of equipment maintenance, cost, and stability of production conditions.

[0163] (e) In this embodiment, in the non-thermal processing by irradiation with an ultrashort pulse laser, the AR film 13 is irradiated with the ultrashort pulse laser in a defocused setting. By irradiating the laser light in this defocused setting, the beam energy can be dispersed on the surface of the AR film 13 irradiated with the laser light, thereby realizing uniform film removal processing. This is particularly useful when the height of the irradiated area may vary due to the influence of the surface shape of the AR film 13.

[0164] (f) In this embodiment, non-thermal processing by irradiation with an ultrashort pulse laser is performed under predetermined conditions, thereby suppressing damage to the exposed surface of the ZrO2 layer 13c as a high refractive index layer that is exposed by removing SnO2 and layers on the surface thereof. Specifically, the ratio t1 / t2 of the thickness t1 of the ZrO2 layer 13c at the removed portion to the thickness t2 of the ZrO2 layer 13c at the non-removed portion, such as the SiO2 layer 13a, falls within a range of, for example, 0.90 to 1.00, preferably 0.95 to 1.00, and more preferably 0.99 to 1.00. In this way, in the ZrO2 layer 13c, the film thickness is not reduced due to the above-mentioned removal processing, or even if the film thickness is reduced, the amount of reduction is suppressed to be extremely small. Therefore, when applied to eyeglass lens products, it is extremely preferable for marking a decorative pattern on an eyeglass lens without causing a deterioration in the quality of the product.

[0165] (5) Other Although embodiments of the present invention have been described above, the above disclosure presents exemplary embodiments of the present invention. That is, the technical scope of the present invention is not limited to the exemplary embodiments described above, and various modifications are possible without departing from the spirit of the present invention.

[0166] As an aspect of the present invention, A method for manufacturing a spectacle lens, the method comprising: irradiating one surface of the spectacle lens with a laser to perform marking for desired processing, the spectacle lens having anti-reflection films different from each other on the object-side surface and the eyeball-side surface, the method comprising: The spectral reflectance characteristics of the anti-reflection coating provided on either the object-side surface or the eyeball-side surface are determined, and a wavelength in a range where the reflectance is relatively low in the ultraviolet region (for example, in the range of 200 to 400 nm) or the infrared region (in the range of 800 to 1100 nm) is determined as the laser wavelength to be applied to the laser processing; The laser wavelength can be used to perform laser processing in a method for manufacturing eyeglass lenses.

[0167] Also, A method for manufacturing a spectacle lens, the method comprising: irradiating one surface of the spectacle lens with a laser to perform marking for desired processing, the spectacle lens having anti-reflection films different from each other on the object-side surface and the eyeball-side surface, the method comprising: determining the spectral reflectance characteristics of the anti-reflection coatings provided on the object-side surface and the eyeball-side surface, and determining the surface with a relatively lower reflectance in the ultraviolet region (for example, in a range of 200 to 400 nm) or the infrared region (for example, in a range of 800 to 1100 nm) as the surface to be laser processed; The laser wavelength to be applied to the laser processing is within the range of the ultraviolet region or the infrared region, whichever region has the lower reflectance, on the determined surface. It may also be a method for manufacturing eyeglass lenses.

[0168] In the above-described embodiment, a case where a decorative pattern is marked by non-thermal processing using an ultrashort pulse laser is taken as an example, but the present invention is not limited to this. In other words, the non-thermal processing using an ultrashort pulse laser may be used to perform some kind of patterning on the optical surface of an optical component, and can be applied in exactly the same way to markings other than decorative patterns.

[0169] In the above-described embodiment, the outermost layer of the AR film 13 is a SiO2 layer 13a serving as a low-refractive index layer, and below the SiO2 layer 13a is a SnO2 layer 13b serving as a high-refractive index reactive layer. Further below is a ZrO2 layer 13c serving as a high-refractive index layer. When the SnO2 reacts with the laser and is partially removed, the SiO2 is also removed, thereby exposing the ZrO2 layer 13c serving as a high-refractive index layer. However, the present invention is not limited to this. The AR film 13 may also be formed by laminating layers other than the SiO2 layer 13a, SnO2 layer 13b, and ZrO2 layer 13c.

[0170] Furthermore, the outermost layer of the AR film 13 may be a low-refractive index layer other than the SiO2 layer 13a. The high-refractive index layer may be a layer other than the SnO2 layer 13b or the ZrO2 layer 13c. For example, the SnO2 layer 13b serving as a reactive layer may be replaced with a thin, conductive ITO layer.

[0171] In the above-described embodiment, a case is exemplified in which the SnO layer, which is a reaction layer included in the AR film 13, and the SiO layer 13a, which is the outermost layer immediately above it, are removed by non-thermal processing using an ultrashort pulse laser. This, as described above, provides the effect of suppressing film peeling. In this manner, non-thermal processing using an ultrashort pulse laser can be performed to remove a predetermined number of layers, including the outermost layer. Even when removing multiple layers, including the outermost layer, non-thermal processing using an ultrashort pulse laser can suppress damage to the exposed surfaces of the layers that will be exposed by the removal, thereby suppressing the reduction in film thickness that accompanies the removal process.

[0172] In other words, even when multiple layers including the outermost layer are removed, for the layer immediately below the removed layer, the ratio t1 / t2 of the thickness t1 of the removed portion to the thickness t2 of the non-removed portion will be, for example, in the range of 0.90 or more and 1.00 or less, preferably 0.95 or more and 1.00 or less, and more preferably 0.99 or more and 1.00 or less.

[0173] In this embodiment, the spectacle lens before laser processing has an anti-reflection film provided on each of the object-side and eyeball-side surfaces.

[0174] The antireflection film provided on the surface to be irradiated with laser (e.g., the surface on the eyeball side) has a reflectance relatively lower than that of the antireflection film provided on the other surface (e.g., the surface on the object side) for the applicable wavelength of the laser used (hereinafter referred to as the first antireflection film). The first antireflection film is also referred to as the antireflection film (1).

[0175] For example, in this embodiment, the wavelength of the laser irradiation is in the ultraviolet range, so that the antireflection film described in Japanese Patent No. 6530765 can be used as the first antireflection film.

[0176] Alternatively, it may be an anti-reflection film used on the rear surface (surface on the eyeball side) as described in Japanese Patent No. 5966011. These are films whose reflectance is lower in the ultraviolet range than in other wavelength ranges.

[0177] Alternatively, the reflectance characteristics of the anti-reflection film (first anti-reflection film) on the surface on which laser irradiation is performed (e.g., the surface on the eyeball side) are preferably 10% or less, and more preferably 5% or less, for the applicable wavelength set for laser irradiation. The reflectance characteristics of the antireflection film (second antireflection film) provided on the other surface (for example, the surface on the object side) can be 20% or more, or may be 25% or more, for a set applicable wavelength.

[0178] Alternatively, the reflectance characteristics of the antireflection film (first antireflection film) on the surface to be irradiated with laser (e.g., the surface on the eyeball side) are such that, when the applicable wavelength is 355 nm, the reflectance is preferably 10% or less, more preferably 5% or less, for wavelengths in the range of 355±10 nm.Also, when the applicable wavelength is 266 nm, the reflectance is preferably 10% or less, more preferably 5% or less, for wavelengths in the range of 266±10 nm.

[0179] Examples of the first antireflection film used in this embodiment include the following: For example, the first antireflection film may have an average reflectance of 10% or less in a wavelength range of 355±10 nm, or an average reflectance of 10% or less in a wavelength range of 266±10 nm.

[0180] Alternatively, a material having a reflectance of 10% or less, preferably 8% or less, for light of any wavelength within the wavelength range of 330 to 400 nm can be used, or a material having an average reflectance of 10% or less, preferably 8% or less, for light of any wavelength within the wavelength range of 250 to 300 nm, or a material having a reflectance of 10% or less, preferably 8% or less, for light of any wavelength within the wavelength range of 250 to 300 nm can be used.

[0181] The first antireflection film can have a reflectance of 15% or less, preferably 10% or less, over the entire visible wavelength range of 350 to 700 nm, or 10% or less over the entire visible wavelength range of 350 to 700 nm.

[0182] Furthermore, the eyeglass lens before laser processing in this embodiment has an anti-reflection film on each of the object-side and eyeball-side surfaces, and the anti-reflection film (e.g., the first anti-reflection film) provided on the surface to be irradiated (e.g., the eyeball-side surface) can be one described in WO2020 / 067409. This film has low reflectance in the infrared range, and is therefore useful when irradiating using the applicable wavelength in the ultraviolet range.

[0183] As in the case of ultraviolet light described above, the reflectance characteristics of the antireflection film (first antireflection film) on the surface to be irradiated with laser light (e.g., the surface on the eyeball side) are preferably 30% or less, and more preferably 25% or less, for the set applicable wavelength.

[0184] The reflectance characteristics of the antireflection film (second antireflection film) provided on the other surface (for example, the surface on the object side) can be 40% or more, or even 50% or more, for a set applicable wavelength. The second antireflection film is also referred to as antireflection film (2).

[0185] Alternatively, the reflectance characteristics of the anti-reflection film (first anti-reflection film) on the surface on which laser irradiation is performed (for example, the surface on the eyeball side) are such that, when the applicable wavelength is 1064 nm, the reflectance is preferably 30% or less for wavelengths in the range of 1064±10 nm, and more preferably 25% or less.

[0186] The anti-reflection film provided on one surface (e.g., the eyeball side) of the spectacle lens used in this embodiment can be exemplified by the following: For example, the average reflectance in the wavelength range of 1064±10 nm can be 25% or less.

[0187] Alternatively, a reflectance of 30% or less, more preferably 25% or less, for light of any wavelength within the wavelength range of 1000 to 1100 nm can be used.

[0188] Depending on the design of the anti-reflective coating, the reflected light may appear blue (such as in so-called blue-cut lenses that have an enhanced ability to block blue light), or green or purple, because the reflected color in the visible light range enters the viewer's eyes.

[0189] When the laser processing according to this embodiment is performed on the spectacle lens of the above specific example, the following advantageous effects are achieved.

[0190] For example, if laser processing is performed on an anti-reflection film with a high reflectance of light in the blue region, the spectacle lens 1 will appear blue when viewed by a third party facing in front of the wearer of the spectacle lens 1.

[0191] On the other hand, the area where the laser processing was performed (decorative pattern 3) appears in the color of the layer exposed by the laser processing (yellow or gold, which is the color of the high refractive index layer in this specific example).

[0192] As a result, to a third party facing the front of the wearer of the eyeglass lens 1, the decorative pattern 3 on the eyeglass lens 1 fitted into the frame can be seen with an aesthetic appearance, providing the effect of distinguishing the lens and a design effect.

[0193] The above-described aspect of good contrast when the decorative pattern 3 is viewed can be achieved whether the laser processing is performed on the multilayer films on the object side surface of the eyeglass lens or on the eyeball side surface.

[0194] Regardless of the laser processing performed on each multilayer film on either surface, the decorative pattern will not enter the wearer's field of vision and interfere with the wearer's field of vision. In other words, the eyeglass lens having the decorative pattern 3 of this embodiment does not obstruct the wearer's clear field of vision.

[0195] Furthermore, when another person observes the wearer's lenses, the decorative pattern 3 is clearly visible when the lenses are in a predetermined relative position (or angle) relative to indoor lighting or sunlight, but is not visible when the lenses are not in the above-mentioned relative position. Therefore, added value in terms of design can be imparted to the lenses by changes in visibility, such as the appearance and disappearance of the predetermined decorative pattern 3. On the other hand, when the lenses are not in the above-mentioned predetermined relative positional relationship, they are recognized by another person as ordinary clear lenses (or predetermined color lenses, photochromic lenses, or polarized lenses).

[0196] The decorative pattern 3 of this embodiment can be formed within the frame-cut lens area, and can carry desired letters, symbols, or patterns on the lens or apply desired designs to the lens without affecting the function of the eyeglasses.

[0197] The decorative pattern 3 of this embodiment is a pattern that can be seen from both the processed surface side and the back surface side of the lens.

[0198] Therefore, the technical concept of the present invention also extends to eyeglass lenses, which are optical elements manufactured by the method for manufacturing optical elements according to this embodiment, or to eyeglasses in which eyeglass lenses, which are optical elements according to this embodiment, are fitted into frames.

[0199] Each multilayer film on each surface of the spectacle lens preferably includes one or more high refractive index layers and one or more low refractive index layers, and the total number of layers is 10 or less (preferably 9 or less, and more preferably 8 or less).

[0200] FIG. 6 shows the surface of the processed area when processing is performed with a pulsed laser on a sample of a spectacle lens according to one specific example, the sample having an anti-reflection film on each of the object side and the eyeball side. Figure 6A is a photograph showing the result of applying an anti-reflection coating (2) to the object-side surface of this spectacle lens of one specific example and processing it using a pulsed laser beam with a wavelength of 355 nm and a pulse width of 10 picoseconds or more but less than 20 picoseconds. The right image is an enlarged view. 6B is a photograph showing the results of processing an anti-reflection film (1) on the eyeball-side surface of a spectacle lens of one specific example using a pulsed laser beam with a wavelength of 355 nm and a pulse width of 10 picoseconds or more but less than 20 picoseconds. The right image is an enlarged view. 6A and 6B, the light colored areas correspond to the laser scan area 16, and the dark colored areas indicate the non-processed areas. 6C shows the reflection characteristics (simulation data) of the antireflection coatings (1) and (2) of the spectacle lens of the above example, with the vertical axis representing reflectance (%) and the horizontal axis representing wavelength (nm). Here, the antireflection coating on the surface facing the eyeball is designated as antireflection coating (1) (CCV, reference number 1 in the figure), and the antireflection coating on the surface facing the object is designated as antireflection coating (2) (CVX, reference number 2 in the figure).

[0201] In both Figures 6A and 6B, the laser is irradiated and moved horizontally by raster scanning, ultimately processing the entire surface.

[0202] The surface quality after laser processing in Figure 6B (processing from the surface on the eyeball side where the anti-reflection film (1) is provided) is better than that in Figure 6A (processing from the surface on the object side where the anti-reflection film (2) is provided). In other words, removal processing by laser irradiation is performed uniformly, and the exposed surface is highly smooth. Furthermore, no damage to the underlying layer is observed.

[0203] This is related to the fact that the reflectance of anti-reflection coating (1) at the applicable wavelength for laser processing is lower than that of anti-reflection coating (2). At the applicable wavelength of 355 nm used here, the difference between the reflectance of anti-reflection coating (1) and that of anti-reflection coating (2) is 20% or more, with the former being lower. Furthermore, at the applicable wavelength, the reflectance of the surface on which anti-reflection coating (2) is formed (the object side) exceeds 25%, while the reflectance of the surface on which anti-reflection coating (1) is formed (the eyeball side) is 5% or less, which is extremely advantageous for processing.

[0204] In other words, processing from the surface on the eyeball side does not require an excessive increase in output compared to processing from the surface on the object side, and can efficiently cause sublimation or evaporation of the reaction layer under stable conditions, which means that the removal processing is carried out uniformly without damaging the underlying layer.

[0205] FIG. 7 shows the results of determining a specific range of laser power that provides stable processing conditions when processing the antireflection coating (1) and the antireflection coating (2) in the same manner as in FIG.

[0206] Here, as in FIG. 6, pulsed laser light with a wavelength of 355 nm and a pulse width of 10 picoseconds or more and less than 20 picoseconds was used.

[0207] In addition, in Figure 7, the laser power that provides stable processing conditions is indicated by hatching (1) (dots), and the laser power that provides the optimal conditions among these is indicated by hatching (2) (diagonal lines). The optimal is the condition that provides stable processing even when affected by slight fluctuations in laser output due to environmental factors such as temperature changes.

[0208] As a result, stable processing as shown in Figure 6B was obtained at approximately 0.10±0.04 (W) for anti-reflection coating (1) and approximately 0.20 (W) for anti-reflection coating (2), and it was found that the optimal laser power to be applied was 0.09 W and 0.20 W, respectively.

[0209] Here, it was found that the use of anti-reflection coating (1) provided a stable processing range four times wider than that of the use of anti-reflection coating (2), confirming its suitability for mass production.

[0210] Although the above example shows laser processing on the eyeglass-side surface of an eyeglass lens, processing can also be performed on the object-side surface. In this case, processing can be performed on an antireflection film on the object-side surface that has appropriate reflection characteristics for the wavelength of the laser used for irradiation. For example, when antireflection films (1) and (2) with the spectral reflection characteristics shown in Figure 6C are used, if processing is performed with laser light having a wavelength of 280 nm or less, it may be advantageous to process from the object side on which antireflection film (1) is formed. [Explanation of symbols]

[0211] 1...eyeglass lens, 2...frame shape, 3...decorative pattern, 4...scannable range, 11...lens substrate (optical substrate), 12...HC film, 13...AR film, 13a...SiO2 layer (low refractive index layer), 13b...SnO2 layer (high refractive index layer), 13c...ZrO2 layer (high refractive index layer), 14...water-repellent film, 15...non-processed area, 16...laser scan area (patterned area), 21...laser light source section, 22...AOM system section, 23...beam shaper section, 24...galvanometer scanner section, 25...optical system

Claims

1. A method for manufacturing a spectacle lens, the method comprising: irradiating one surface of the spectacle lens with a laser to perform marking for desired processing; the spectacle lens having a multilayer structure including a stack of low refractive index layers and high refractive index layers, each of which is provided with a different anti-reflection film on an object-side surface and an eyeball-side surface, respectively; determining the applicable wavelength of the laser to be used; a laser irradiation step of selecting one of the object-side surface and the eyeball-side surface on which an anti-reflection film having a relatively low reflectance at the applicable wavelength is provided, and irradiating the selected surface with a laser beam at the applicable wavelength; and the laser is an ultrashort pulse laser having a pulse width of 10 femtoseconds or more and less than 100 picoseconds, the antireflection film provided on the one surface includes a reactive layer that is relatively more reactive to irradiation with the ultrashort pulsed laser than other layers included in the antireflection film on the one surface; In the laser irradiation step, a marking is applied to a removed portion formed by at least partially removing a predetermined layer including an outermost layer of the multilayer structure on the one surface, so that the removed portion can be visually recognized by visible light by exposing the high refractive index layer below the reaction layer or a part of the reaction layer remaining thereon; the predetermined layer includes the reaction layer and the low refractive index layer located on an upper layer side of the reaction layer, A method for manufacturing a spectacle lens, wherein a ratio t1 / t2 of a thickness t1 of a removed portion of the low refractive index layer to a thickness t2 of a non-removed portion of the low refractive index layer in the high refractive index layer exposed by removal of the low refractive index layer accompanying at least partial removal of the reaction layer is within a range of 0.90 or more and 1.00 or less.

2. A method for manufacturing a spectacle lens, comprising: a spectacle lens having a multilayer structure including a stack of low refractive index layers and high refractive index layers, each of which is provided with a different anti-reflection film on an object-side surface and an eyeball-side surface, and marking the surface by applying a desired process by irradiating one surface with a laser; selecting a surface from the object-side surface and the eyeball-side surface that has a relatively low reflectance for light in a predetermined wavelength range; a laser irradiation step of applying laser light having a wavelength within the predetermined wavelength range to the selected surface to perform laser irradiation; and the laser is an ultrashort pulse laser having a pulse width of 10 femtoseconds or more and less than 100 picoseconds, the antireflection film provided on the one surface includes a reactive layer that is relatively more reactive to irradiation with the ultrashort pulsed laser than other layers included in the antireflection film on the one surface; In the laser irradiation step, a marking is applied to a removed portion formed by at least partially removing a predetermined layer including an outermost layer of the multilayer structure on the one surface, so that the removed portion can be visually recognized by visible light by exposing the high refractive index layer below the reaction layer or a part of the reaction layer remaining thereon; the predetermined layer includes the reaction layer and the low refractive index layer located on an upper layer side of the reaction layer, A method for manufacturing a spectacle lens, wherein a ratio t1 / t2 of a thickness t1 of a removed portion of the low refractive index layer to a thickness t2 of a non-removed portion of the low refractive index layer in the high refractive index layer exposed by removal of the low refractive index layer accompanying at least partial removal of the reaction layer is within a range of 0.90 or more and 1.00 or less.

3. 3. The method for manufacturing a spectacle lens according to claim 1, wherein the applicable wavelength or the wavelength within the predetermined wavelength range is in the range of 200 to 400 nm or in the range of 800 to 1100 nm.

4. The method for manufacturing a spectacle lens according to claim 1 or 2, wherein the anti-reflection film on the selected surface has a reflectance of 10% or less for the applicable wavelength or wavelengths within the predetermined wavelength range.

5. 3. The method for manufacturing a spectacle lens according to claim 1, wherein the anti-reflection coating on the selected surface has a reflectance at the applicable wavelength or wavelengths within the predetermined wavelength range that is 10% or more lower than that of the other surface.

6. The outermost layer is a low refractive index layer made of SiO ２ The method for manufacturing a spectacle lens according to claim 1 or 2, wherein the layer is a layer.

7. The high refractive index layer is made of ZrO ２ , SnO ２ , Al ２ O ３ 3. The method for manufacturing a spectacle lens according to claim 1, wherein the glass substrate contains either ITO or ITO.

8. The method for manufacturing a spectacle lens according to claim 1 or 2, wherein the reaction layer is a high refractive index layer containing Sn and O.

9. The reaction layer is made of SnO ２ The method for manufacturing a spectacle lens according to claim 8 , wherein the lens comprises at least one of ITO and ITO.

10. A spectacle lens having anti-reflection films, each of which has a multilayer structure including a stack of low refractive index layers and high refractive index layers, different from each other, on an object-side surface and an eyeball-side surface, and having laser marking performed on one surface of the spectacle lens, the antireflection film provided on the one surface has a reflectance lower than that of the antireflection film provided on the other surface with respect to light having a wavelength of at least 200 to 400 nm, and includes a reactive layer having a reactivity to irradiation with an ultrashort pulse laser relatively higher than that of other layers included in the antireflection film on the one surface; a marking is applied to a removed portion formed by at least partially removing a predetermined layer including an outermost layer of the multilayer structure on the one surface by the laser marking, so that the removed portion can be seen by visible light, since the high refractive index layer below the reactive layer or a part of the reactive layer remaining is exposed; the high refractive index layer exposed by removing the predetermined layer has a ratio t1 / t2 of a thickness t1 of a removed portion of the low refractive index layer to a thickness t2 of a non-removed portion of the low refractive index layer in a range of 0.90 or more and 1.00 or less; The high refractive index layer is made of ZrO ２ , SnO ２ , Al ２ O ３ , or ITO.

11. A spectacle lens having anti-reflection films, each of which has a multilayer structure including a stack of low refractive index layers and high refractive index layers, different from each other, on an object-side surface and an eyeball-side surface, and having laser marking performed on one surface of the spectacle lens, the antireflection film provided on the one surface has a lower reflectance with respect to light having a wavelength of at least 800 to 1100 nm than the antireflection film provided on the other surface, and includes a reactive layer having a higher reactivity to irradiation with an ultrashort pulse laser than other layers included in the antireflection film on the one surface; a marking is applied to a removed portion formed by at least partially removing a predetermined layer including an outermost layer of the multilayer structure on the one surface by the laser marking, so that the removed portion can be seen by visible light, since the high refractive index layer below the reactive layer or a part of the reactive layer remaining is exposed; a ratio t1 / t2 of a thickness t1 of a removed portion of the low refractive index layer to a thickness t2 of a non-removed portion of the low refractive index layer, the ratio t1 / t2 being within a range of 0.90 or more and 1.00 or less, of the high refractive index layer exposed by removing the predetermined layer.

12. The outermost layer is a low refractive index layer made of SiO ２ 12. The spectacle lens according to claim 10 or 11, which is a layer.

13. The high refractive index layer is made of ZrO ２ , SnO ２ , Al ２ O ３ 12. The eyeglass lens according to claim 11, comprising either ITO or ITO.

14. The eyeglass lens according to claim 10 or 11, wherein the reaction layer is a high refractive index layer containing Sn and O.

15. The reaction layer is made of SnO ２ 15. The spectacle lens according to claim 14, comprising:

16. A pair of eyeglasses having a frame fitted with a spectacle lens manufactured by the spectacle lens manufacturing method according to claim 1 or 2, or a pair of eyeglasses having a frame fitted with the spectacle lens according to claim 10 or 11.

Images