Mandrel used in the processing of ophthalmic lenses

Abstract

A mandrel (1) for holding an ophthalmic lens member blank (52) during processing is disclosed. The mandrel (1) includes a front face (6) for receiving the ophthalmic lens member blank (52) to be processed, a rear face (8) opposite the front face, and one or more through holes (10) extending between the front face and the rear face (6, 8). In use, wax applied to the rear face (8) contacts the ophthalmic lens member blank (52) received on the front face (6) through the one or more through holes (10). Also disclosed is a method of manufacturing an ophthalmic lens using such a mandrel, and a lens manufactured using such a mandrel.

Description

Technical Field

[0001] The present disclosure relates to mandrels used in the processing of ophthalmic lenses, particularly (but not limited to) contact lenses. The present disclosure relates to a mandrel for holding an ophthalmic lens member blank during processing, a component kit including such a mandrel, a method of attaching an ophthalmic lens member blank onto the mandrel, a method of processing an ophthalmic lens member blank, and an ophthalmic lens processed using such a mandrel and / or method.

Background Art

[0002] Ophthalmic lenses are often manufactured by processing (machining) an ophthalmic lens blank, for example to provide a desired shape and surface finish. A high degree of accuracy is required for such operations to ensure that the finished lens has the required properties. A mandrel is used to hold the ophthalmic lens blank during processing (machining). For example, it is used to attach the lens blank to a lathe for cutting, or to hold the lens blank during polishing or grinding.

[0003] Typically, a block of wax is provided on the front surface of the mandrel and the lens blank is pressed into the wax. Thereby, the wax fixes and holds the lens blank in place. Obtaining an accurate placement of the lens blank on the wax and obtaining a consistent thickness of the wax is difficult. This can result in misalignment of the lens blank or tilting relative to the mandrel, leading to processing errors. The wax can also leave residues on the surface of the lens, resulting in a hazy or cloudy appearance on the surface, which can affect the optical performance of the lens. Subsequently, the wax residues must be cleaned. If the cleaning is not successful or (as often happens) the cleaning damages the lens, the lens will not achieve the required optical performance (due to either the scratch or the wax residue). It would be advantageous to provide a method for holding an ophthalmic lens blank during processing to reduce processing errors, to provide a lens with improved optical performance, and / or to provide a reduced error rate for the lenses being manufactured.

[0004] Recently, ophthalmic lens assemblies have been proposed in which optical components (optical parts) are housed (built-in) within a lens. Examples of optical components include diffractive optical elements and electrically switchable components such as liquid crystal cells. Such an assembly can be manufactured by encapsulating the optical component between a first lens member and a second lens member. The first lens member and the second lens member can define the front and rear surfaces of the lens therebetween, or alternatively, the first lens member and the second lens member can define an encapsulating component. The encapsulating component is then encapsulated (enclosed) within the lens material to form the front and / or rear surfaces of the lens. It is advantageous to provide an efficient method of machining (machining) such a lens assembly. Such an assembly may require more precise machining (machining) to achieve the required dimensions, taking into account the number of components involved (e.g., considering the stacking of tolerances), and / or may require a higher level of machining accuracy to allow the optical component to provide the required effect. Thus, more precise machining techniques can be particularly advantageous when applied to such ophthalmic lens assemblies.

[0005] As an alternative to using wax, a mandrel may be provided with a recess that exactly corresponds to (matches) the dimensions of the lens blank, such that the lens is held on the mandrel by an interference fit between the recess and the blank. However, the tight fit between the lens blank and the recess can result in excessive force on the blank during machining, and there is a possibility that the lens after cutting may be distorted. Furthermore, this technique may be limited with respect to the shape of the blank that can be used. For example, it is difficult to use a thin edge and place it on the side surface of the recess, so it is difficult to machine a blank with a very thin edge using this method. It is advantageous to provide a method of holding an ophthalmic lens blank during machining, reducing the error rate, providing a lens with improved optical performance, and / or allowing a wider range of lens blank shapes to be machined.

[0006] The present disclosure aims to alleviate the aforementioned problems. Alternatively or additionally, the present disclosure aims to provide an improved apparatus and / or method for use in the processing of ophthalmic lens blanks. SUMMARY OF THE INVENTION

[0007] In a first aspect, the present disclosure provides a mandrel for holding an ophthalmic lens member blank during processing, the mandrel comprising a front face for receiving the ophthalmic lens member blank to be processed, a rear face opposite the front face, and one or more through holes extending between the front face and the rear face, wherein in use, wax applied to the rear face contacts the ophthalmic lens member blank received on the front face via the one or more through holes.

[0008] In a second aspect, the present disclosure provides a component kit comprising the mandrel according to the first aspect, the mandrel having a socket in the front face for receiving an adapter, the component kit being characterized by including one or more of the following: an adapter having a convex end configured to be received in the socket such that the convex end defines a part of the front face of the mandrel, an adapter having a concave end configured to be received in the socket such that the concave end defines a part of the front face of the mandrel, an adapter having a flat end configured to be received in the socket such that the flat end defines a part of the front face of the mandrel.

[0009] In a third aspect, the present disclosure provides a method of attaching an ophthalmic lens member blank onto a mandrel, the mandrel having a front surface, a rear surface, and one or more through-holes extending between the front surface and the rear surface, the method comprising holding the ophthalmic lens member blank against the front surface of the mandrel, applying wax to the rear surface of the mandrel while the ophthalmic lens member blank is held against the front surface of the mandrel, and allowing the wax to flow through the one or more through-holes and contact the rear surface of the ophthalmic lens member blank at the through-holes.

[0010] In a fourth aspect, the present disclosure provides a method of processing an ophthalmic lens member blank, the method comprising attaching the ophthalmic lens member blank onto a mandrel according to the method of the third aspect, releasing the holding such that the lens member blank is held on the mandrel by the wax, and processing the front surface of the ophthalmic lens member blank while the lens member blank is held on the mandrel.

[0011] In a fifth aspect, the present disclosure provides a batch of 1000 ophthalmic lenses, each lens being processed using the mandrel of the first aspect and / or the second aspect and / or manufactured using the method of the third aspect and / or the fourth aspect, each lens comprising a central optical zone and an annular peripheral zone surrounding the central optical zone, wherein the central optical zone of each lens is free of wax residue and scratches, and at least one of the lenses has an annular peripheral zone including a surface with wax residue and / or scratches.

[0012] In a sixth aspect, the present disclosure provides an ophthalmic lens processed using the mandrel of the first aspect and / or the second aspect and / or manufactured using the method of the third aspect and / or the fourth aspect, the lens comprising a central optical zone and a peripheral zone surrounding the central optical zone, wherein the central optical zone is free of wax residues and scratches, and the peripheral zone includes a surface having wax residues and / or scratches.

[0013] Optional but preferred features are set forth in the dependent claims.

[0014] Of course, it will be understood that features described in connection with one aspect of the present disclosure may be incorporated into other aspects of the present disclosure. For example, the methods of the present disclosure may incorporate any of the features described with reference to the apparatus of the present disclosure, and vice versa.

[0015] Exemplary embodiments are described by way of example only, with reference to the accompanying schematic diagrams. BRIEF DESCRIPTION OF THE DRAWINGS

[0016]

Figure 1A

[0017]

Figure 1B

[0018]

Figure 1C

[0019]

Figure 2A

[0020]

Figure 2B

[0021]

Figure 2C

[0022]

Figure 3A

[0023]

Figure 3B

[0024]

Figure 3C

[0025]

Figure 4

[0026]

Figure 5

[0027]

Figure 6

[0028]

Figure 7

DETAILED DESCRIPTION OF THE INVENTION

[0029] According to a first aspect of the present disclosure, a mandrel for holding an ophthalmic lens member blank during processing (machining) is provided. The mandrel may include a front surface for receiving an ophthalmic lens member blank to be processed (machined), a rear surface opposite the front surface, and / or one or more through-holes extending between the front surface and the rear surface. The mandrel may be configured such that, in use, wax applied to the rear surface contacts an ophthalmic lens member blank attached to the front surface via the one or more through-holes.

[0030] The use of such a mandrel may allow wax to be applied to the ophthalmic lens member blank at one or more individual positions defined by the through-holes. The lens member blank positioned relative to the front surface may be contacted by (and subsequently held by) the wax at the openings of the through-holes on the front surface of the mandrel. Thereby, the accuracy when the lens member blank is positioned on the mandrel can be improved, and there is no variation introduced by the need to apply a wax layer having a certain thickness and / or push the lens member blank into the wax layer to a certain depth, reducing machining errors. Additionally or alternatively, controlling and restricting the area where the wax contacts the lens member blank may reduce the impact of wax residues on the optical performance of the lens.

[0031] The term machining may refer to cutting, grinding, polishing, and / or other machining processes. Examples of machine tools to which the present disclosure may be applied may include lathes, grinding machines, polishing machines, and / or other machine tools.

[0032] The front surface of the mandrel may comprise an optical zone and a peripheral zone, and the one or more through-holes may be disposed within the peripheral zone. Disposing the through-holes within the peripheral zone may place wax residues outside the optical zone, thereby improving the optical performance of the lens. The optical zone of the front surface may be disposed at the center of the front surface. The mandrel may be configured such that when the lens member blank is received on the front surface, the optical zone of the front surface is aligned with the optical zone of the lens member blank. The peripheral zone of the front surface may be radially outside the optical zone, and for example, the peripheral zone may be annular and may surround the optical zone. The mandrel may be configured such that when the lens member blank is received on the front surface, the peripheral zone of the lens member blank is aligned with the peripheral zone of the front surface. The through-holes of the mandrel may be limited to the peripheral zone. The through-holes extending between the front surface and the rear surface may be located within the peripheral zone. The front surface of the mandrel may be convex, concave or flat within the optical zone.

[0033] The front surface of the mandrel, e.g., the optical zone, may have a concave bowl-shaped surface area configured to receive the convex surface of the lens member blank. The front surface of the mandrel, e.g., the optical zone, may have a convex dome-shaped surface area configured to receive the concave surface of the lens member blank. The bowl-shaped area or the dome-shaped area may be surrounded by a planar surface area. The front surface of the peripheral zone may have a substantially planar surface. Thus, the shape of the front surface may conform to the shape of the front or rear surface of the lens member blank.

[0034] The mandrel may have a stem for attaching the mandrel to a machine tool. The stem may have an elongated body configured to be received within a chuck of the machine tool. The mandrel may have a flange extending radially (radially) from the stem, for example, at one end of the stem. The flange may have a front face, a rear face (e.g., the face opposite the front face of the flange) and / or one or more through holes. The diameter of the stem may be less than 50% of the diameter of the flange. The front face and / or the rear face may be substantially perpendicular to the stem (regardless of the recess formed therein). The longitudinal axis of the through hole may be substantially parallel to the longitudinal axis of the stem and / or the rotational axis of the mandrel when attached to the machine tool.

[0035] The mandrel may comprise a plurality of through holes. The plurality of through holes may be spaced around the longitudinal axis of the mandrel and / or the stem. The through holes may be equally spaced around the longitudinal axis.

[0036] The front surface of the mandrel may have a forward recess shaped to receive an ophthalmic lens member blank. The forward recess may be configured to receive the lens member blank by, for example, a location fit rather than an interference fit. "Location fit" may be defined as a fit where the dimensions of the recess match those of the blank, and the blank is substantially immobile within the recess in the radial direction, but the blank will fall out of the recess when the mandrel is inverted in the absence of wax that holds the blank in place. This is in contrast to an interference fit where the blank is held within the recess even when the mandrel is inverted in the absence of wax. The dimensions of the forward recess may exactly match those of the ophthalmic lens member blank. Providing a forward recess having a shape that exactly matches the shape of the lens member blank can improve the accuracy and reliability when the lens member blank is positioned on the mandrel (thereby reducing processing errors). The forward recess may have a diameter of 4 mm or more and 20 mm or less, for example 10 mm or more and 20 mm or less. The optical zone of the mandrel may be substantially circular and may have a diameter of 2 mm or more and 10 mm or less. In some embodiments, the forward recess may have a diameter of 13 mm to 15 mm, and the optical zone of the mandrel may have a diameter of 7 mm to 9 mm. The depth of the forward recess may be 1 mm or less, for example, the depth at the outer edge of the forward recess may be 0.8 mm to 0.2 mm. The depth of the forward recess may be less than the thickness of the lens member blank at the outer edge of the forward recess. The depth of the forward recess may vary according to the radius, for example, when the front surface includes a convex or concave region within the optical zone. Providing a shallow recess may allow mandrels with a wider range of lens thicknesses to be used while machining the entire surface of the lens blank. The depth may be measured with reference to the outer edge of the front surface of the mandrel, for example, the outer edge of the front surface of the flange. When the longitudinal position of the outer edge of the front surface of the mandrel varies along the circumference, the average position of the front edge needs to be used when measuring the depth of the recess. The forward recess may be defined by a raised region, for example, an annular raised region. The raised region may be centered on the mandrel and may be disposed, for example, on the front surface.The raised region may be concentric with the front recess, the optical zone, and / or the peripheral zone.

[0037] The rear surface of the mandrel may have a rear recess, such as an annular recess. The rear recess may be centered on the rear surface and / or may be concentric with the rear surface. The rear recess may be centered on the flange and / or may be concentric with the longitudinal axis of the flange and / or the mandrel. The depth of the rear recess may be greater than the depth of the front recess. The depth of the rear recess may be 5 mm or less, for example, the depth may be 0.5 mm to 4 mm. The depth may be measured based on the position of the outermost edge of the rear surface, such as the outer edge of the rear surface of the flange. When the longitudinal position of the outer edge of the rear surface varies along the circumference, the average position of the rear edge should be used when measuring the depth of the recess. A plurality of through-holes, for example each through-hole or all through-holes, may be in fluid communication with the rear recess and / or may be in fluid communication with each other through the rear recess. Therefore, the wax distributed in the rear recess may be able to flow into the plurality of through-holes. By providing a rear recess through which wax can be provided to the plurality of through-holes, the user can easily distribute (inject) wax into the rear recess (rather than distributing (injecting) it individually into each hole). This may help to provide a more uniform distribution of the wax, thereby improving the reliability of the holding provided by the mandrel during use and / or improving the ease of use / efficiency of use (e.g., by reducing the number of wax distribution steps).

[0038] Each through-hole may have a first opening on the front surface and a second opening on the rear surface. The first opening may be located within the front recess and / or the second opening may be located within the rear recess. The through-hole may extend between the first opening and the second opening. Thus, the first opening and the second opening may define the ends of the through-hole. The first opening may be located at the bottom of the front recess. The second opening may be located at the bottom of the rear recess. The through-hole has a longitudinal axis. The through-holes may be substantially circular, kidney-shaped and / or arcuate when viewed in a cross-section perpendicular to their longitudinal axes, for example, arcuate with a constant radius with respect to the center of the front surface. The perimeters (i.e., the edges of each opening) of the first opening and the second opening may be curved and may not include discontinuities (non-smooth portions) such as sharp corners, for example.

[0039] The front surface of the mandrel may have one or more drainage channels through which wax and / or air can flow from the front recess. By providing the drainage channels, excess wax can be discharged from the region of the through-holes, reducing the variation in the amount of wax protruding beyond the openings of the through-holes on the front surface (which can affect the position of the lens member blank on the front surface and increase the risk of machining errors). Additionally or alternatively, providing the drainage channels can reduce the risk of air bubbles forming between the blank and the mandrel. The drainage channels may extend from the edge of the front recess. The drainage channels may extend from the edge of the through-hole, for example, the opening of the through-hole. Drainage channels extending directly from the through-holes on the front surface may be particularly advantageous in reducing the accumulation of excess wax.

[0040] The front surface may have a raised area that defines a front recess. The front surface may further have a reservoir, for example, located radially outside the raised area. The reservoir may be connected to the front recess by one or more of the drainage channels, allowing excess wax in the front recess to flow through the drainage channels into the reservoir. The front surface of the raised area may be substantially planar (regardless of the presence of the drainage channels). Providing a reservoir on the front surface can be a mechanical and simple way to collect excess wax and thereby avoid the wax contacting the lens member blank outside the intended area. The reservoir may be deeper than the front recess. The drainage channels may extend radially and linearly from the front recess to the reservoir. This arrangement can facilitate the flow of wax from the front recess to the reservoir. The reservoir may take the form of an annular channel that defines the outer perimeter of the raised area.

[0041] In some embodiments, the front recess is substantially circular, the raised area is substantially annular, and the reservoir is substantially annular. The front recess, the raised area, and the reservoir may be concentric and may be in the order of the front recess, the raised area, the reservoir, from the inside to the outside.

[0042] In a second aspect of the present disclosure, a component kit is provided that includes a mandrel having any of the features described above in connection with the first aspect. The mandrel may further include a socket within the front face for receiving an adapter. The component kit may further include one or more of the following: an adapter having a convex (dome-shaped) end configured to be received within the socket such that the convex end defines a portion of the front face of the mandrel; an adapter having a concave (bowl-shaped) end configured to be received within the socket such that the concave end defines a portion of the front face of the mandrel; an adapter having a flat end configured to be received within the socket such that the flat end defines a portion of the front face of the mandrel. Thus, the adapter can be used to provide a convex or concave region on the front face, as described above in the first aspect. Such a reconfigurable mandrel / kit can provide improved manufacturing efficiency and / or ease of manufacture.

[0043] In a third aspect of the present disclosure, a method is provided for attaching an ophthalmic lens member blank, such as a contact lens member blank, onto a mandrel for machining (i.e., as part of a machining process). The mandrel may include a front face, a rear face, and one or more through-holes extending between the front face and the rear face. The method may include holding the ophthalmic lens member blank against the front face of the mandrel, such as holding the rear face of the ophthalmic lens member blank against the front face of the mandrel. The method may include applying wax to the rear face of the mandrel while the ophthalmic lens member blank is held against the front face of the mandrel. The method may include flowing the wax through the one or more through-holes and contacting the rear face of the ophthalmic lens member blank at the through-holes while the ophthalmic lens member blank is held against the front face of the mandrel.

[0044] The method may comprise a step in which the wax contacts only the rear surface of the ophthalmic lens member blank in the through-hole. The method may comprise a step of allowing the wax to solidify. The method may comprise a step of releasing the holding of the lens member blank (e.g., after the wax has solidified), and a step in which the blank is held by the wax.

[0045] The method may comprise a step of placing the ophthalmic lens member blank on a support, for example, on a support having a bowl-shaped recess or a dome-shaped protrusion on its upper surface so as to conform to (imitate) the front surface of the blank. The method may comprise a step of placing a mandrel on the lens member blank on the support such that, for example, the weight of the mandrel itself holds the lens member blank against the front surface of the mandrel. The method may comprise a step of dispensing wax onto the rear surface of the mandrel, for example, while the mandrel is placed on the lens member blank and the rear surface of the mandrel is at the top. The method may comprise a step of holding the mandrel and, optionally, a step of pressing down the mandrel, before and / or during the wax dispensing step. It will be apparent that the force required to hold the blank against the mandrel depends in part on the pressure, flow rate and amount (volume) of the wax being dispensed. When the wax is dispensed at a low pressure and slowly in a volume substantially equal to the volume of the through-hole, the wax will not push the blank away from the front surface, and thus little or substantially no force is required to hold the blank in place. When higher flow rates (flow velocities), pressures and volumes are involved, it may be necessary to hold (press) the blank against the surface with a certain amount of force. The method may comprise a step of using a fixture having a cavity configured to receive a part of the stem, for example, to hold the mandrel in place while the wax is being dispensed. The use of the support and the fixture may assist in maintaining the alignment between the mandrel and the lens member while the wax is being applied, thereby reducing the risk of machining errors.

[0046] In a fourth aspect of the present disclosure, a method of machining (fabricating) an ophthalmic lens member blank is provided. The method includes the step of attaching the ophthalmic lens member blank onto a mandrel according to the method of the third aspect. The method may include the step of attaching the mandrel (with the blank attached thereto by wax) onto a machine tool. For example, the mandrel may be attached to the machine tool by inserting the stem of the mandrel into a chuck. The method may include the step of machining the front surface of the ophthalmic lens member blank. The method may include the step of releasing the holding of the ophthalmic lens member blank (which may be called an ophthalmic lens member when the forming is completed) from the mandrel, for example, by melting the wax. The method may include the step of performing a further finishing process on the ophthalmic lens member.

[0047] The method may include the step of receiving the ophthalmic lens member blank in a location fit within a front recess of the mandrel. The method may include the step of dispensing wax into a rear recess of the mandrel.

[0048] The ophthalmic lens member blank can have a front surface that becomes the front surface when the lens is used in the eye. The ophthalmic lens member blank can have a rear surface that becomes the rear surface when the lens is used in the eye. The rear surface can have, for example, a concave (bowl-shaped) region surrounded by a planar region. The front surface can have, for example, a convex (dome-shaped) region surrounded by a planar region. Either the front surface or the rear surface can be positioned adjacent to the front surface of the mandrel to enable machining of the other of the front surface or the rear surface. In this context, the surface of the lens member blank adjacent to the front surface of the mandrel is referred to as the rear surface of the lens member blank, and the other surface of the lens member blank is referred to as the front surface. Thus, the front surface of the blank can be referred to as either the front surface or the rear surface at different times depending on the orientation of the blank on the mandrel. When the front surface of the lens member blank is machined and the rear surface is adjacent to the front surface, the mandrel can have a convex (dome-shaped) surface region. When the front surface of the lens member blank is machined and the rear surface is adjacent to the front surface, the mandrel can have a concave (bowl-shaped) surface region. Providing a front surface that mimics (matches) the shape of the lens member blank to be machined can provide improved accuracy in positioning the lens member on the mandrel.

[0049] The method may comprise a step of holding one of the front and rear surfaces of the lens member blank against the front surface of the mandrel, a step of applying wax as described in the method of the third aspect, and then a step of machining the other of the front and rear surfaces, and (optionally, a step of performing any of the steps of the other methods with the lens member blank attached to the mandrel in that orientation). The method may comprise a step of removing the lens member blank from the mandrel after machining (machining) of its surface is completed. The method may be repeated to machine the other of the front and rear surfaces of the same lens member blank. The method may comprise a step of holding one of the machined front and rear surfaces of the lens member blank against the front surface of the mandrel, a step of applying wax as described in the method of the third aspect, and then a step of machining the other of the front and rear surfaces, and (optionally, a step of performing any of the steps of the other methods with the lens member blank attached to the mandrel in that orientation). The method may comprise a step of removing the lens member blank from the mandrel after machining (machining) is completed. Accordingly, the method may provide a method of attaching and / or machining a lens member blank to provide a lens member.

[0050] The method may comprise the steps of holding the front surface of the first lens member blank against the front surface of the mandrel, applying wax as described in the method of the third aspect, and then machining the rear surface, and (optionally, performing any of the steps of the other methods described above with the first lens member blank attached to the mandrel in that orientation), and then removing the first lens member blank from the mandrel after machining (machining) of its surface is complete. The method may then comprise the steps of holding the machined rear surface of the first lens member blank against the front surface of the mandrel, applying wax as described in the method of the third aspect, and then machining the other of the front and rear surfaces. The method may comprise attaching one or more optical components on the first lens member blank, for example on the front surface of the lens member blank. The method may comprise attaching a second lens member blank on the first lens member blank. The method may then comprise machining the front surface of the second lens member blank (and, optionally, performing any of the steps of the other methods described above with the second lens member blank attached to the mandrel in that orientation) while the second lens member blank is attached to the first lens member blank and thereby held on the mandrel. Thus, the method may provide a method of attaching and / or machining a lens member assembly.

[0051] Machining (machining) may include, for example, cutting, polishing, grinding on a lathe, or any other machining operation where the lens needs to be held and supported.

[0052] The following paragraphs describe aspects of ophthalmic lenses related to any of the aspects of the present disclosure described above or below.

[0053] The ophthalmic lens may include a central optical zone and an annular peripheral zone surrounding the central optical zone, and the first and second regions having wax residues may be disposed within the peripheral zone. The lens may have a plurality of regions having wax residues spaced apart within the peripheral zone.

[0054] The ophthalmic lens may include one or more optical components such as diffractive optical elements, and an electrically switchable component including a liquid crystal cell. The ophthalmic lens may include one or more optical components disposed between a first ophthalmic lens member and a second ophthalmic lens member.

[0055] The ophthalmic lens may include an ophthalmic lens member manufactured by processing (machining) an ophthalmic lens member blank. The ophthalmic lens may include a lens member blank whose front surface (i.e., the front surface when used on the eye) and / or rear surface (i.e., the back surface when used on the eye) has been processed (machined). The ophthalmic lens may include a single lens member blank whose front surface and / or rear surface has been processed (machined). Alternatively, the ophthalmic lens may include two (or more) lens member blanks, and each blank may have its front surface and / or rear surface processed (machined). The ophthalmic lens may include a first lens member whose rear surface has been processed (machined) and a second lens member whose front surface has been processed (machined). For example, the second lens member is fixed to the first lens member, and optionally, one or more optical components are disposed therebetween. In some embodiments, the first and second lens members define an encapsulated component and are themselves encapsulated within the lens material to form a lens. In other embodiments, the ophthalmic lens may be formed by the first lens member and the second lens member only.

[0056] The optical zone of the lens member can be centered on the optical axis. The optical axis can be aligned with the center of the lens member. The optical zone of the lens or lens member includes the portion of the lens that has an optical function during use. The optical zone can be configured to be positioned above or in front of the pupil of the eye during use. In a plan view, the lens member can have an optical zone surrounded by a peripheral zone. The peripheral zone is located outside the optical zone and is not part of the optical zone. When the lens member is worn, the peripheral zone can be positioned above the iris. The peripheral zone can provide a mechanical function, such as increasing the size of the lens member to facilitate handling of the lens. The peripheral zone can extend to the edge of the lens member. The peripheral zone can provide a ballast to prevent rotation of the lens member and / or provide a shaped area that improves the comfort of the lens wearer.

[0057] As used herein, an ophthalmic lens can be an eyeglass lens or a contact lens. The lens can include one or more lens members manufactured by processing (machining) one or more lens member blanks. A contact lens can include one or more contact lens members manufactured by processing (machining) one or more contact lens member blanks.

[0058] The contact lens can be a hard contact lens or a soft contact lens such as a hydrogel contact lens or a silicone hydrogel contact lens. As used herein, the term contact lens refers to an ophthalmic lens that can be placed on the front surface of the eye. It will be understood that such contact lenses provide clinically acceptable eye movement and do not restrict a person's eye.

[0059] Contact lenses can be used to correct or improve vision associated with myopia, presbyopia, hyperopia, astigmatism, or other refractive abnormalities. The contact lenses can be soft contact lenses such as hydrogel contact lenses or silicone hydrogel contact lenses. The contact lenses may be rigid gas permeable contact lenses. The contact lenses may be scleral contact lenses.

[0060] The contact lens (and thus the contact lens member blank) can include an elastomeric material, a silicone elastomeric material, a hydrogel material, a silicone hydrogel material, or combinations thereof. As understood in the field of contact lenses, a hydrogel is a material that retains water in an equilibrium state and does not contain a silicone-containing compound. A silicone hydrogel is a hydrogel that contains a silicone-containing compound. As described in the context of the present disclosure, hydrogel materials and silicone hydrogel materials have an equilibrium water content (EWC) of at least 10% to about 90% (wt / wt). In some embodiments, the hydrogel material or the silicone hydrogel material has an EWC of about 30% to about 70% (wt / wt). In comparison, as described in the context of the present disclosure, silicone elastomeric materials have a water content of about 0% to less than 10% (wt / wt). Typically, the silicone elastomeric materials used in the present method or apparatus have a water content of 0.1% to 3% (wt / wt).Examples of suitable lens formulations (compositions) include those having the following United States Adopted Names (USAN): methafilcon A, ocufilcon A, ocufilcon B, ocufilcon C, ocufilcon D, omafilcon A, omafilcon B, comfilcon A, enfilcon A, stenfilcon A, fanfilcon A, etafilcon A, senofilcon A, senofilcon B, senofilcon C, narafilcon A, narafilcon B, balafilcon A, samfilcon A, lotrafilcon A, lotrafilcon B, somofilcon A, riofilcon A, delefilcon A, verofilcon A, kalifilcon A, laefilcon A, etc.

[0061] Alternatively, the lens (and thus the lens member blank) can contain, consist essentially of, or consist of a silicone elastomer material. For example, the lens can contain, consist essentially of, or consist of a silicone elastomer material having a Shore A hardness of 3 to 50. The Shore A hardness can be determined using conventional methods (e.g., using method DIN 53505) as understood by those skilled in the art. Other silicone elastomer materials can be obtained, for example, from NuSil Technology, or from Dow Chemical Company.

[0062] Alternatively, the lens (and lens member blank) can contain polymethyl methacrylate (PMMA).

[0063] The contact lens can have a substantially circular shape. The contact lens can have a diameter of 4 mm or more and 20 mm or less, for example 10 mm or more and 20 mm or less. The optical zone of the contact lens can have a substantially circular shape and can have a diameter of 2 mm or more and 10 mm or less. In some embodiments, the contact lens can have a diameter of 13 mm to 15 mm, and the optical zone can have a diameter of 7 mm to 9 mm. The contact lens can have a convex front surface. The contact lens can have a concave rear surface.

[0064] In a fifth aspect of the present disclosure, a batch of 1000 ophthalmic lenses, for example a batch of 1000 contact lenses, is provided. Each lens of the batch can be processed (machined) using the mandrel of the first aspect and / or the second aspect, and / or using the method of the third aspect and / or the fourth aspect. Each lens can include a central optical zone and an annular peripheral zone surrounding the central optical zone, and the central optical zone of each lens is free of wax residue and / or scratches, and at least one of the lenses can have a peripheral zone including a surface with wax residue and / or scratches. The peripheral zone can be an annular peripheral zone.

[0065] Conventional lens processing methods that use wax to hold the lens member on the mandrel produce a large number of lenses with wax residue in the optical zone and / or scratches in the optical zone (which can occur by removing the wax residue). In known methods using wax, the error rate of these defects does not result in less than one per 1000 lenses. On the other hand, lenses manufactured using the mandrel of the present disclosure can avoid such defects by restricting the area where the wax contacts the lens blank to the peripheral zone.

[0066] At least 10 percent, for example at least 20 percent, of the lens may have an annular peripheral zone that includes a surface with wax residue and / or a scratched surface.

[0067] It will be understood that a plurality of lenses of a batch are manufactured continuously. As used herein, "manufactured continuously" means that the batch is composed of a plurality of lenses that are manufactured one after another without intervening lenses that do not form part of the batch.

[0068] As used herein, "wax residue" refers to wax visible to the naked eye left on the surface of the lens / lens member.

[0069] As used herein, "scratch" refers to one or more scratches visible to the naked eye on the surface of the lens or lens member.

[0070] The area with wax residue may correspond to the position of the through-hole when the lens is held against the front surface of the mandrel. The peripheral zone comprises a surface having a first area with wax residue and a second area with wax residue, and the first area may be spaced apart from the second area. Each area may correspond to the position of the through-hole.

[0071] Each ophthalmic lens may include a first ophthalmic lens member, a second ophthalmic lens member, and one or more optical components located between the first and second ophthalmic lens members. There may be no wax residue and / or scratches in the optical zones of each of the first and second lens members. The at least one lens may comprise a first and / or second lens member having an annular peripheral zone that includes a surface with wax residue and / or a scratched surface.

[0072] In a sixth aspect of the present disclosure, an ophthalmic lens processed (machined) using the mandrel of the first aspect and / or the second aspect and / or using the method of the third aspect and / or the fourth aspect is provided. The lens may include a central optical zone and a peripheral zone surrounding the central optical zone. The central optical zone may be free of wax residues and scratches, and the peripheral zone may include a surface having wax residues and / or being scratched. The lens of the sixth aspect may have any of the features described above with respect to the fifth aspect (or any other aspect) of the present disclosure.

[0073] Referring to FIGS. 1A, 1B, and 1C, a mandrel 1 according to an embodiment of the present disclosure is illustrated. The mandrel includes a stem 2 and a flange 4 provided at one end of the stem 2 and extending radially (radially) outward from the stem 2. The flange 4 defines a part of the front surface 6 of the mandrel located on the opposite side of the flange 4 with respect to the stem 2 and a rear surface 8 located on the opposite side of the front surface 6 with respect to the flange 4. Two through holes 10 penetrate the flange 4 between the front surface 6 and the rear surface 8. The through holes 10 are located on both sides of the stem 2 and appear circular when viewed in the plane of FIG. 1B. A front recess 12 is formed on the front surface 6 by a rim 14 extending around the flange 4. A rear recess 16 is formed on the rear surface 8 by a rim 18 extending around the flange 4. The through holes 10 extend between the bottom of the front recess 12 and the bottom of the rear recess 16. The mandrel 1 includes a dome 20 that defines a part of the front surface 6. The dome 20 is concentrically arranged with the flange 4 and the stem 2 and is arranged on the opposite side of the flange 4 with respect to the stem 2. The dome 20 is centered on the front optical zone 22, and the through holes 10 are arranged in an annular peripheral zone 24 outside the optical zone 22. In FIG. 1B, the dashed line indicates the range of the optical zone 22.

[0074] Figure 1C shows a schematic cross-sectional view of the mandrel 1 of FIG. 1A with the contact lens member assembly 50 fixed using wax (not shown). The contact lens member assembly 50 includes a first lens member blank 52 and a second lens member blank 54. The second lens member blank 54 is concentrically mounted on the first lens member blank 52, and a plurality of optical components 56 are encapsulated (enclosed) between the first lens member blank 52 and the second lens member blank 54. Each of the first and second lens member blanks 52, 54 includes an optical zone 53 disposed at the center of the lens member and an annular peripheral zone 55 disposed concentrically with the optical zone 53 and surrounding the optical zone 53. In FIG. 1C, the contact lens member assembly 50 is arranged such that the rear surface of the first lens member blank 52 abuts against the front surface 6 of the mandrel 1, and the front surface of the second lens member blank 54 becomes the front surface 60 of the assembly 50 and can be machined thereafter. Accordingly, the back surface 58 of the first lens member blank 52 is concave within the optical zone 53 and planar within the peripheral zone 55, thereby conforming to the shape of the front surface 6 defined by the flange 4 and the dome 20. The through hole 10 is disposed within the peripheral zone 55. Although FIGS. 1C and the following embodiments relate to contact lens members and contact lens member assemblies, it will be understood that other ophthalmic lens members / lens member assemblies can be processed (machined) using the mandrel of the present disclosure. FIG. 1C illustrates a contact lens member assembly formed by two contact lens members, but it will be understood that a single contact lens member or a contact lens member assembly formed by more than two lens members can also be processed (machined) using the mandrel of the present disclosure. A batch can include 1000 contact lenses, and each lens can be formed by a contact lens member assembly 50 as shown in FIG. 1C.

[0075] In use, wax is dispensed into the rear recess 16, flows into the through hole 10, and contacts the rear surface 58 of the first lens member 52. In this way, the lens assembly is fixed at a predetermined position on the mandrel, but the wax contacts the rear surface 58 only at the location where the through hole 10 opens at the front surface 6. This can enable the location where the wax contacts the lens assembly to be controlled, for example, limited to the non-optical region of the lens. For example, in FIG. 1C, since the through hole 10 is located within the peripheral zone 55, clouding of the lens as a result of the wax does not affect the optical zone 53.

[0076] Referring to FIGS. 2A, 2B, and 2C, a mandrel 1 according to a second embodiment of the present disclosure is illustrated. Here, only aspects of the second embodiment that are different from the first embodiment are described. The same reference numerals are used to indicate similar elements (e.g., the through hole 10) between the first embodiment and the second embodiment. In contrast to the first embodiment, the mandrel 1 of the second embodiment has a total of six through holes 10, namely, four kidney-shaped through holes 10a (kidney-shaped through holes) that appear kidney-shaped in plan view and two circular through holes 10b (circular through holes) that appear circular in plan view. The two circular through holes 10b are located opposite each other around the front recess 12 of the peripheral zone 24 (shown in FIG. 2B), and the four kidney-shaped through holes 10a form two opposing pairs on both sides of the peripheral zone 24. The optical zone 22 (shown in FIG. 2B) is flat. An annular raised region 60 extends around the outside of the peripheral zone 24, and an annular reservoir 62 extends around the outside of the peripheral zone 24. The annular raised region 60 includes several radially extending channels (flow paths) 64, and each flow path extends from the through hole 10 to the annular reservoir 62.

[0077] In use, excess wax can flow from the through hole 10 through the radially extending groove 64 into the annular reservoir, thereby avoiding the excess wax from contacting the rear surface of the lens member located on the mandrel.

[0078] Figures 3A, 3B, and 3C illustrate mandrel 1 according to the third embodiment of the present disclosure. Here, only aspects of the third embodiment that differ from the first embodiment will be described. Similar reference numerals are used to indicate similar elements (e.g., through-hole 10) between the first and third embodiments. In contrast to the first embodiment, the mandrel 1 of the third embodiment has three kidney-shaped through-holes 10 equally spaced along the circumference of flange 4 within peripheral zone 24 (shown in FIG. 3B). Similar to the second embodiment, an annular raised region 60 extends around the outside of peripheral zone 24, and an annular reservoir 62 extends around the outside of peripheral zone 24. The annular raised region 60 includes three radially extending grooves 64, each of which extends from the outer edge of the front recess 12 adjacent to one of the through-holes 10 to the annular reservoir 62.

[0079] In use, excess wax can flow from the through-holes 10 through the radially extending grooves 64 into the annular reservoir, thereby reducing the accumulation of excess wax in the region of the through-holes 10. In the third embodiment, although the radially extending grooves 64 are not directly connected to the through-holes 10, they can still provide an advantage in reducing contact between the wax outside the region of the through-holes 10 and the rear surface of the lens member.

[0080] As clearly illustrated in FIG. 3C, an axial cavity 66 extends along the length of mandrel 1. The axial cavity 66 provides a socket into which an adapter 67 including a domed end 69 can be inserted to support a lens member mounted thereon and defining a convex portion of front face 6. The provision of the axial cavity 66 can thereby provide a more flexible mandrel that can be reconfigured for use during machining of the front and rear faces of the lens member blank.

[0081] FIG. 4 illustrates a state where a mandrel 1 according to an exemplary embodiment of the present disclosure is attached to a chuck 68 of a lathe (not shown) for cutting with a cutting tool 70. Wax 72 is filled in the through hole 10 and the rear recess 16 and is in contact with the rear surface 58 of the first lens member blank 52 received in the front recess 12. In use, the cutting tool 70 cuts the front surface 74 of the first lens member, which is the front surface of the lens member in FIG. 4. Although FIG. 4 illustrates the mandrel 1 within the lathe, it will be understood that other machining operations such as polishing and / or grinding may be performed using the mandrel of the present disclosure.

[0082] FIG. 5 shows a flowchart of an exemplary method according to the present disclosure. A lens member blank is held against the front surface of the mandrel (100). Next, wax is dispensed onto the rear surface of the mandrel (102), flows into the through hole (104), and contacts the rear surface of the lens member blank adjacent to the front surface of the mandrel. Optionally, the method may include the following further steps (individually or in combination), and the optional steps are shown by dashed lines in FIG. 5. After the wax has flowed to and contacted the surface of the lens member blank (104), the wax is allowed to cure (108). Next, the holding of the blank is released, but the lens member blank is held in place by the wax (110). Next, the mandrel is attached within a lathe (or other machine tool) such that the stem of the mandrel is received within, for example, the chuck of the lathe (112). Next, the front surface of the lens member blank is machined (114), for example, cut. Next, the wax is melted and the lens member blank is removed from the mandrel (116).

[0083] When machining is required on both the front and rear surfaces of the lens member, the foregoing steps are performed such that the front surface of the lens member contacts the wax and the rear surface of the lens member is machined. After the lens member is released from the mandrel (116), the foregoing steps are performed such that the rear surface of the lens member contacts the wax and the front surface of the lens member is machined (alternatively, it may be the reverse). The resulting lens member is then sent to a finishing process. Depending on which of the front or rear surface is machined, reconfiguration of the mandrel (e.g., by changing between adapters of different shapes) or a mandrel of a different shape may be required to support the lens.

[0084] When a lens member assembly including two lens members is required, the foregoing steps are performed such that the front surface of the first lens member contacts the wax and the rear surface of the first lens member is machined. Next, the method may include repeating the foregoing steps 100-110 with the rear surface of the first lens member blank held against the front surface of the mandrel. Optionally, steps 112-114 are repeated such that the front surface of the first lens member is machined. An optical component, e.g., an optoelectronic component, is then attached onto the front surface of the first lens member blank. Next, the second lens member blank is fixed to the first lens member blank such that its front surface is close to the first lens member blank. Next, steps 112-116 are repeated such that the rear surface of the second lens member blank is machined and the assembly is removed from the mandrel. The resulting lens member assembly is sent to a finishing process.

[0085] FIG. 6 shows an exploded view of a mandrel 1, a lens member blank 52, a first support 80, and a second support 82, according to an embodiment of the present disclosure. The lens member blank 52 is shown above the first support 80, and the uppermost surface of the first support 80 has a bowl-shaped cavity 84 corresponding to the shape of the front surface (front face in FIG. 6) of the lens member blank 52. The mandrel 1 is shown above the lens member blank 52 with its front face facing downward, and the second support 82 is shown above the mandrel 1. The lowermost surface of the second support 82 has a cylindrical cavity 84 corresponding to the shape of the stem of the mandrel. In use, the lens member blank 52 is placed on the first support 80 with the dome on its front face received within the bowl-shaped cavity 84. Next, the mandrel 1 is placed on the lens member blank 52, and its front face abuts against the rear face of the lens member blank 52. Next, the second support 82 is placed on the mandrel 1, and the stem of the mandrel 1 is received within the cylindrical cavity 86. Both the second support 82 and the first support 80 hold the mandrel 1 and the lens member blank 52 in an aligned state while wax is applied to the mandrel 1. In FIG. 6, the state in which the front face of the lens member blank is arranged for machining is shown. It will be understood that it is desirable to replace the bowl-shaped cavity 84 with a domed surface in order to more appropriately support the lens member blank 52 when the rear face is machined.

[0086] FIG. 7 shows a photograph of a contact lens member according to an embodiment of the present disclosure. Wax residues 99 are shown in three separate regions on the peripheral zone of the lens member. For clarity, dashed lines indicating the approximate extent of the regions have been added to the photograph. FIG. 7 shows a lens member that is combined with a second lens member to form an encapsulated component, which is then encapsulated within a lens material to form a lens.

[0087] Although the present disclosure has been described and illustrated with reference to particular embodiments, it will be understood by those skilled in the art that the present disclosure can be useful in many different variations not particularly illustrated herein.

[0088] In the foregoing description, integers or elements having known obvious or predictable equivalents have been mentioned, but such equivalents are incorporated herein as if they were individually described herein. To determine the true scope of the present disclosure, reference should be made to the claims. The claims should be construed to cover any such equivalents. Also, it will be understood by the reader that the integers or features of the present disclosure described as being preferred or advantageous or convenient or the like are optional and do not limit the scope of the independent claims. Further, while such optional integers or features may be beneficial in some embodiments of the present disclosure, they may not be desirable in other embodiments and thus may not be present in other embodiments, and this should be understood.

Claims

**Claim 1** A mandrel for holding an ophthalmic lens member blank during processing, comprising: a front surface for receiving the ophthalmic lens member blank to be processed; a rear surface opposite to the front surface; one or more through-holes extending between the front surface and the rear surface; and in use, wax applied to the rear surface contacts the ophthalmic lens member blank received on the front surface through the one or more through-holes. The mandrel is characterized by the above. **Claim 2** The front surface includes a central optical zone and an annular peripheral zone, and the one or more through-holes are located within the peripheral zone. The mandrel according to claim 1, characterized by the above. **Claim 3** The front surface of the mandrel is convex, concave, or flat within the optical zone. The mandrel according to claim 2, characterized by the above. **Claim 4** a stem for attaching the mandrel to a machine tool; a flange extending radially from the stem; and the flange has the front surface, the rear surface, and the one or more through-holes. The mandrel according to any one of claims 1 to 3, characterized by the above. **Claim 5** The mandrel has a longitudinal axis and a plurality of through-holes spaced circumferentially around the longitudinal axis. The mandrel according to any one of claims 1 to 4, characterized by the above. **Claim 6** The through-holes are spaced equidistantly around the longitudinal axis. The mandrel according to claim 5, characterized by the above. **Claim 7** The front surface has a front recess formed to receive the ophthalmic lens member blank, for example, by position adaptation. The mandrel according to any one of claims 1 to 6, characterized by the above. **Claim 8** The rear surface has a rear recess, for example, an annular recess. The mandrel according to any one of claims 1 to 7, characterized by the above. **Claim 9** Each through-hole has a first opening on the front surface and a second opening on the rear surface, and optionally, the first opening is located within the front recess and / or the second opening is located within the rear recess. The mandrel according to claim 7 or 8, characterized by the above. **Claim 10** The front surface has a raised annular region defining the front recess and an annular reservoir located radially outside the raised region. The reservoir is connected to the front recess by one or more drainage channels, and excess wax in the front recess can flow into the reservoir through the drainage channels. The mandrel according to claim 9, characterized in that.

11. The through hole has a longitudinal axis, When viewed in a cross section perpendicular to the longitudinal axis, the through hole is substantially circular, kidney-shaped and / or arcuate, for example, arcuate with a certain radius with respect to the center of the front surface. The mandrel according to any one of claims 1 to 10, characterized in that.

12. The lens member blank is a contact lens member blank, for example, a contact lens member blank for soft contact lenses such as hydrogel contact lenses or silicone hydrogel contact lenses or for rigid gas permeable contact lenses. The mandrel according to any one of claims 1 to 11, characterized in that.

13. A component kit comprising the mandrel according to any one of claims 1 to 12, The mandrel has a socket in the front surface for receiving an adapter, including one or more of the following The component kit is characterized in that: An adapter having a convex end, configured to be received in the socket such that the convex end defines a part of the front surface of the mandrel. An adapter having a concave end, configured to be received in the socket such that the concave end defines a part of the front surface of the mandrel. An adapter having a flat end, configured to be received in the socket such that the flat end defines a part of the front surface of the mandrel.

14. A method of attaching an ophthalmic lens member blank, for example a contact lens member blank, onto a mandrel, The mandrel has a front surface, a rear surface, and one or more through holes extending between the front surface and the rear surface, The method comprises: Holding the ophthalmic lens member blank against the front surface of the mandrel, Applying wax to the rear surface of the mandrel while the ophthalmic lens member blank is held against the front surface of the mandrel. the wax flowing through the one or more through-holes and contacting the rear surface of the ophthalmic lens member blank in the through-holes A method characterized by comprising the above. **Claim 15** The ophthalmic lens member blank is positioned and received in a forward recess formed in the front surface of the mandrel, the wax is distributed in a rearward recess formed in the rear surface of the mandrel, the one or more through-holes extend between the forward recess and the rearward recess The method according to claim 14, characterized by the above. **Claim 16** A method for processing an ophthalmic lens member blank, comprising: attaching the ophthalmic lens member blank onto a mandrel according to the method described in claim 14 or 15; releasing the holding so that the lens member blank is held on the mandrel by the wax; processing the front surface of the ophthalmic lens member blank while the lens member blank is held on the mandrel; A method characterized by comprising the above. **Claim 17** while holding a first ophthalmic lens member blank against the front surface, applying wax to the rear surface of the mandrel, the wax flowing through the one or more through-holes and contacting the rear surface of the ophthalmic lens member blank in the through-holes including while the first ophthalmic lens member blank is held on the mandrel by the wax, attaching one or more optical components onto the first ophthalmic lens member blank; fixing a second ophthalmic lens member blank to the first ophthalmic lens member blank, the optical component being positioned between the first ophthalmic lens member blank and the second ophthalmic lens member blank; processing the front surface of the second lens member blank; including The method according to claim 16, characterized by the above. **Claim 18** A batch of 1000 ophthalmic lenses, each lens being processed using the mandrel according to any one of claims 1 to 13 and / or manufactured using the method according to any one of claims 14 to 17, each lens comprising a central optical zone and a peripheral zone surrounding the central optical zone, the central optical zone of each lens being free of wax residues and scratches, At least one of the lenses has a peripheral zone including a surface with wax residue and / or scratches A batch characterized by this.

19. Each ophthalmic lens includes a first ophthalmic lens member, a second ophthalmic lens member, and one or more optical components disposed between the first ophthalmic lens member and the second ophthalmic lens member The batch according to claim 18, characterized by this.

20. Each lens is a contact lens, for example, a soft contact lens such as a hydrogel contact lens or a silicone hydrogel contact lens, or a rigid gas permeable contact lens The batch according to claim 18 or 19, characterized by this.

21. An ophthalmic lens processed using the mandrel according to any one of claims 1 to 13 and / or manufactured using the method according to any one of claims 14 to 17, wherein the lens includes a central optical zone and a peripheral zone surrounding the central optical zone, there is no wax residue or scratches in the central optical zone, the peripheral zone includes a surface with wax residue and / or scratches An ophthalmic lens characterized by this.

Images