Method for tinting or bleaching a lens, lenses obtainable by the method for tinting or bleaching a lens, lenses including tinting or bleaching, lens holder and tinting device for tinting a lens

Abstract

To provide a method for coloring or decoloring a lens, an obtainable lens, a colored or decolored lens, a lens holder, and a coloring device enabling more complicated (gradient) coloring.SOLUTION: A lens can be obtained by a method comprising displacing a geometric center of the lens from a rotational axis of a lens holder or by using the lens holder in which a receiving unit is displaced from the rotational axis. The lens holder rotates at least 360°. A figure a) shows a lens with eccentric halo tinting. A figure b) shows a lens with an inverted eccentric halo. A figure c) shows a pair of lenses with eccentric halo tinting. In a figure d), a halo is only partially applied to the lens.SELECTED DRAWING: Figure 2B

Description

[Technical Field]

[0001] The present invention relates to the tinting of lenses, in particular the tinting of spectacle lenses. In particular, the invention relates to a method for tinting or bleaching lenses, lenses obtainable by said method, lenses comprising the tint or bleaching, a lens holder and a tinting device for producing lens tints of complex design, in particular decentered halo and pendulum tints.

[0002] Furthermore, the invention relates to a corresponding computer program for carrying out said method. [Background technology]

[0003] Tinting eyeglass lenses is sought after for both fashion and medical reasons. While solid tinted lenses are most commonly used for sunglasses, gradient tinting has become increasingly important in recent years, offering additional benefits. Generally, the concept of gradient tinting is to have a full tint at the top of the lens while allowing the user to see more light or full light in the lower field of view, thereby providing glare protection and clear vision when, for example, driving a car. The principle of such gradient tinted eyeglasses is to increase visibility by enlarging the iris due to the upper shading, allowing more light to enter from the actual field of view, such as the road or a computer. Similarly, lenses with a darker shade at the bottom and a lighter shade at the top are also available on the market.

[0004] The most common way to impart a gradient tint to a lens is to (partially) immerse the lens in a tinting bath and gradually remove it from the bath so that the parts of the lens that are exposed longer to the colorant become darker.

[0005] Despite these benefits of standard gradient coloring, a large amount of glare can still enter the eyes in many situations, causing unnecessary eye strain and eye fatigue. This is especially true during demanding visual activities such as watching television, working in front of a display, or reading, because this light from the periphery of the visual field is not conducive to proper viewing. On the contrary, this light causes vision-impairing refractions and reflections in the eye and reduces the opening of the iris, thereby reducing the amount of light allowed into the eye. This can cause computer displays in the field of view to appear dark, while ambient light can be perceived as undesirably bright.

[0006] In such situations, the linear gradient tint described above is supplemented with a circular gradient tint, but the tint density of the lens increases from the center to the periphery of the lens, i.e., not just in one direction but all around the lens. These types of tints allow all (or nearly all) light in from the central field of view while filtering out damaging and distracting ambient light from other directions.

[0007] U.S. Patent No. 5,201,955 describes an annular gradient optical lens tinting system for tinting eyeglass lenses in which the lenses are mounted in a frame that rotates about an axis centered and perpendicular to the lens plane while reciprocating vertically to produce an annular gradient tint that is darker at the outer edge of each lens and gradually lighter toward the center, the optical center of the lens being either completely clear or significantly lighter than the rest of the lens.

[0008] However, the variety of eyeglass frames and the various anatomical situations of customers require a better fit and therefore a more complex tint gradient of the lens. For example, the lens of U.S. Pat. No. 5,201,955 does not fit all eyes equally. Summary of the Invention [Problem to be solved by the invention]

[0009] It is an object of the present invention to provide an improved method for tinting or bleaching lenses, improved lenses obtainable by the method, improved lenses including tinting or bleaching, improved lens holders, and improved tinting devices. The inventors have recognized that it is desirable to be able to achieve more complex (gradient) tinting. In particular, it would be advantageous to provide a method, lens holder, and tinting device that allows for (novel) decentered halo and pendulum lens tinting, especially asymmetric and / or polychromatic decentered halo and pendulum lens tinting. Furthermore, it would be advantageous to provide lenses with corresponding halo and / or pendulum tinting or bleaching designs. [Means for solving the problem]

[0010] To better address one or more of these problems, a first aspect of the present invention provides a first method for tinting or bleaching a lens, the first method comprising: inserting a lens into a receiving unit of a lens holder; providing an immersion bath containing a fluid; immersing the lens holder in the fluid; and rotating the lens holder around a rotation axis that is generally perpendicular to the plane of the lens to a predetermined maximum rotation angle, the rotation axis being external to the lens. In this case, the rotation axis does not coincide with the geometric (or optical) center of the lens, i.e., does not pass through the geometric (or optical) center of the lens, and the lens holder can be rotated without restriction, i.e., 360° or less or more. However, in this case, the rotation can also be limited to remain less than 360°. Preferably, the rotation axis is external to the receiving unit of the lens holder.

[0011] Immersing the lens holder in the fluid particularly includes moving the lens holder in a direction perpendicular to the surface of the immersion bath, and more particularly includes repeatedly moving the lens holder in a direction perpendicular to the surface of the immersion bath.

[0012] According to a second aspect of the present invention, there is provided a second method for tinting or bleaching a lens, the second method comprising inserting a lens into a lens holder, providing an immersion bath containing a fluid, immersing the lens holder in the fluid, and rotating the lens holder about an axis of rotation to a predetermined maximum rotation angle, the axis of rotation being generally perpendicular to the plane of the lens, the second method further comprising removing the lens holder from the immersion bath, changing the fluid, displacing the lens in a direction parallel to the plane of the lens relative to the axis of rotation and rotating the lens (within the lens holder (in the plane of the lens)), and immersing the lens holder in the same or another immersion bath.

[0013] According to a third aspect of the present invention, there is provided a third method for tinting or bleaching a lens, the third method comprising inserting a lens into a lens holder, providing an immersion bath containing a fluid, immersing the lens holder in the fluid to a maximum immersion depth, and rotating the lens holder about a rotation axis to a maximum rotation angle, the rotation axis being generally perpendicular to the plane of the lens, the third method being characterized in that the maximum rotation angle is predetermined and the maximum immersion depth of the lens holder in the immersion bath is adapted in accordance with the predetermined maximum rotation angle, or the maximum immersion depth is predetermined and the maximum rotation angle is adapted in accordance with the predetermined maximum immersion depth of the lens holder in the immersion bath.

[0014] According to a fourth aspect of the invention, there is provided a lens obtainable by any of the above methods.

[0015] According to a fifth aspect of the present invention, there is provided a lens comprising a tint or bleaching, characterized in that the tint or bleaching comprises at least one selected from the group consisting of an annular gradient, a partial annular gradient, or a pendulum gradient with the center of the gradient outside the lens, and at least two different gradients comprising either an annular gradient, a partial annular gradient, or a pendulum gradient. For example, the lens may comprise two partial annular tints in two different areas of the lens having two different colors. Similarly, the lens may comprise two pendulum tints in different areas on the lens.

[0016] In general, the annular gradient may comprise a halo or a portion of a halo. Furthermore, the lens may have a pendulum gradient produced by pendulum-like movement of the lens in the immersion bath, in particular asymmetric pendulum-like movement of the lens in the immersion bath, i.e., movement in a first direction to a first angle and movement in a second direction to a second angle, the first angle (and first direction) being different from the second angle (and second direction). In particular, the tinting or bleaching of the provided lens is not rotationally symmetric about the geometric center of the lens.

[0017] According to another aspect of the present invention, there is provided a lens holder including a receiving unit configured to hold a lens in a first plane and a rotation axis generally perpendicular to the first plane, the lens holder configured to rotate about the rotation axis, the lens holder characterized in that the rotation axis is external to the lens. In particular, the receiving unit includes a receiving area generally perpendicular to the rotation axis, the (geometric center of) the receiving area configured to be displaced from the rotation axis such that the rotation axis is external to the lens or even external to the receiving area. Preferably, the rotation axis is also external to the receiving unit. Furthermore, the lens holder may be configured to rotate about the rotation axis during immersion of the lens holder in an immersion bath.

[0018] According to a further aspect, a first tinting device for tinting a lens is provided, the first tinting device including a lens holder (the lens holder including a receiving unit configured to hold the lens in a first plane and a rotation axis generally perpendicular to the first plane, the lens holder configured to rotate about the rotation axis, the lens holder characterized in that the rotation axis is external to the lens), an immersion bath containing a fluid, the lens holder configured to be immersed in the fluid, and a rotation unit configured to rotate the lens holder about the rotation axis of the lens holder up to a predetermined maximum rotation angle.

[0019] According to another aspect of the present invention, there is provided a second tinting device for tinting lenses, the second tinting device including a lens holder, an immersion bath containing a fluid, wherein the lens holder is configured to be immersed in the fluid to a maximum immersion depth, a rotation unit configured to rotate the lens holder around a rotation axis to a maximum rotation angle, and a lift unit configured to move the lens holder in a direction perpendicular to the surface of the immersion bath, wherein the second tinting device is characterized in that the maximum rotation angle is predetermined and the lift unit is configured to adapt the maximum immersion depth of the lens holder into the immersion bath according to the predetermined maximum rotation angle, or the maximum immersion depth is predetermined and the rotation unit is configured to adapt the maximum rotation angle according to the predetermined immersion depth of the lens holder into the immersion bath.

[0020] According to yet another aspect, a computer program, particularly a non-transitory computer program, is provided, including program code means that, when executed on a computer or processing unit, cause the computer to control a first or second tinting device to perform any of the steps of the above-described method. The basic concept of the present invention is to provide a method for tinting or bleaching a lens that allows for novel lens movement in an immersion bath. In particular, in conventional lens holders, the lens is generally positioned such that its geometric or optical center coincides with the axis of rotation, causing the lens holder to rotate when immersed in the immersion bath. However, such a configuration limits the production of lens tints. Therefore, a concept is to position the axis of rotation external to the lens. It is also a concept to provide a tinting method that includes at least two tinting cycles, for example, to produce lenses with two different colors. A further concept is to adapt the immersion depth of the lens holder in the immersion bath according to the maximum rotation angle, or vice versa.

[0021] In this way, a wide range of novel, non-rotationally symmetric lens tints (or bleaches) can be obtained. In fact, novel, non-rotationally symmetric lens tints and bleaches can be obtained regardless of the (maximum) rotation angle used. For example, a lens rotated about an axis displaced from its geometric center so that the axis of rotation is external to the lens can be rotated a first angle, e.g., 45°, in a first direction, then rotated a second direction, e.g., 90°, and then rotated again a 90° in the first direction. In other words, the method can involve an asymmetric pendulum-like movement in an immersion bath, leading to an entirely novel lens tint or bleach.

[0022] Another concept is to provide at least two tinting cycles, with the parameters of the cycles differing from one another. For example, after a first immersion of the lens holder in an immersion bath, the lens holder is removed from the immersion bath and the fluid is changed, or the lens is displaced relative to the axis of rotation, or the lens is rotated (e.g., around its geometric center) before being immersed in the same or another immersion bath. In this way, highly complex tinting designs that cannot be produced using conventional tinting methods can be achieved. Such lenses can provide targeted adaptation of tinting for aesthetic reasons and for controlling the amount of light reaching the eye from specific areas of the lens, while at the same time allowing for good manufacturability. For example, bicolor lenses can be obtained, especially bicolor lenses in which the two colors have different tinting or bleaching patterns on the lens. Naturally, lenses with three or more colors can also be obtained.

[0023] Another concept is to adapt the (maximum) immersion depth of the lens holder into the immersion bath according to a predetermined maximum rotation angle, or to adapt the maximum rotation angle according to the (predetermined maximum) immersion depth of the lens holder into the immersion bath. In this way, novel coloring and bleaching designs can also be achieved. Adapting the (maximum) immersion depth according to a predetermined maximum rotation angle implies a fixed relationship between the maximum rotation angle and the immersion depth. For example, if the maximum rotation angle is determined to be 45° in a first rotation direction and 60° in a second direction, and 45° corresponds to a maximum immersion depth of 3 cm, but 60° corresponds to a maximum immersion depth of 4 cm, when the lens holder rotates to the maximum rotation angle in the first direction, the lens holder will be immersed to a depth of 3 cm, and when the lens holder rotates to the maximum rotation angle in the second direction, the lens holder will be immersed to a depth of 4 cm. In other words, the rotation up to a predetermined maximum rotation angle and simultaneous immersion of the lens holder in the immersion bath follows a predetermined pattern, and the maximum rotation angle is linked to a predetermined (maximum) immersion depth (or vice versa). In other words, the (maximum) immersion depth of the lens holder may depend on the (predetermined) maximum rotation angle and / or the maximum rotation angle may depend on the predetermined (maximum) immersion depth.

[0024] In known methods of lens tinting, the immersion in the immersion bath and the rotational movement of the lens holder are completely independent of each other. Therefore, it is almost impossible to reproduce lens tints with the same design. However, in the present invention, the rotational movement and the vertical movement, i.e., the immersion movement, are related to each other according to a predetermined pattern. In other words, the (maximum) rotation angle (or any rotation angle) of the lens holder is linked to the immersion depth of the lens holder in the immersion bath according to a predetermined pattern. In this way, it is guaranteed that lenses with the same tint or bleach design can be reproduced when the same pattern (of tinting or bleaching) is applied in another tinting / bleaching cycle.

[0025] The concept is therefore to adapt a conventional lens holder to include a receiving unit that is (or can be) shifted away from the rotation axis of the lens holder to such an extent that the rotation axis is located outside the lens or outside the receiving unit. In the case of a conventional lens holder, the rotation axis of the lens holder and the geometric (or optical) center of the inserted lens generally coincide. In other words, a conventional lens holder includes a receiving unit that is securely fixed with rotational symmetry around the rotation axis of the lens holder. However, this only allows for limited types of lens tinting, in particular lens tinting that is symmetrical about the geometric (or optical) center of the lens. By providing a rotation axis that is outside the lens or outside the receiving unit, it is also possible to tint the lens according to other designs, in particular designs that are not symmetrical about the center point of the lens.

[0026] Preferred embodiments of the invention are defined in the dependent claims. It is to be understood that the claimed computer program may have similar and / or identical modifications or preferred embodiments to the claimed methods, lens holders or tinting devices, in particular as defined in the dependent claims and disclosed herein.

[0027] The following provides a brief explanation and definition of some terms used throughout this application.

[0028] The term "lens" can generally be understood as a lens blank, i.e., a blank from which, for example, a lens can be cut. However, it can equally be understood as a spectacle lens. Nevertheless, the term "lens" can also include other types of lenses for visual aids, such as microscope or telescope lenses. Furthermore, the term "lens" can also include flat glass, and the term "glass" should be understood as any material suitable for lenses. Thus, the term "glass" also encompasses plastic glass. When flat glass is used, glass that allows distortion-free imaging is particularly meant. Apart from that, the term "lens" can also include any (curved) transparent material, in particular a shield (preferably suitable for the eyes, e.g., that can be worn on the user's nose), more particularly, for example, a helmet shield or a monolens.

[0029] The term "axis of rotation" does not necessarily imply a physical axis, but can include imaginary axes as well.

[0030] The definition of "rotation less than 360°" may include rotation less than 360° in one direction or rotation less than 180° in each of the first and second directions. For example, rotation less than 360° may include rotation of 10° or 359° in one direction. Similarly, rotation less than 360° may include rotation of X° in the first direction and rotation of y° in the second direction, respectively, where (x + y) is less than 360°. For example, rotation less than 360° may include rotation of 179° in the first direction and rotation of 179° in the second direction, respectively.

[0031] The term "receiving unit" defines a part of a lens holder that is specifically configured to receive (and hold) one or more lenses. A receiving unit may include a frame into which one or more lenses can be inserted or a clamp for gripping the lenses. However, any other structure suitable for receiving (and holding) lenses may also be defined as a receiving unit.

[0032] The term "receiving area" may be understood generally as a part of the receiving unit, in particular as the area or space occupied by a lens when received by the receiving unit. For example, if the receiving unit includes a frame configured to hold a lens, the receiving area may be defined as the area inside the frame, i.e., the area surrounded by the frame. Similarly, if the receiving unit includes a rod, in particular a rod including notches configured to hold a lens, the receiving area may be understood as the area surrounded by the rod, or more particularly, the area occupied by the lens when inserted between the rods or between the notches in the rod.

[0033] The term "geometric center" can be understood as commonly defined, i.e., as the arithmetic mean location of all points of an object. Another term often used for geometric center is center of mass.

[0034] The term "fluid" is to be understood as a substance that continuously deforms under an applied shear stress or external force. In particular, a fluid includes a liquid, a gas, or a plasma. In particular, a fluid may include a tinting liquid for tinting a lens or a tinting vapor for tinting a lens, where tinting is to be understood as applying a color and / or a shade to a lens. Similarly, a fluid may include a bleaching liquid for bleaching a lens or a bleaching vapor for bleaching a lens, where a bleaching liquid or a bleaching vapor, i.e., a bleaching fluid, may define any type of liquid or vapor suitable for removing a color from a lens, in particular suitable for bleaching a lens.

[0035] The term "tinting liquid" is to be understood as a liquid containing a coloring agent adapted to tint the lens.

[0036] The term "bleaching liquid" is to be understood as a liquid containing a bleaching substance adapted to bleach the lens.

[0037] The term "gradient" is used to describe, inter alia, the distribution of lens tint or bleaching intensity across the lens surface. In particular, the term "gradient tinting" is used to describe the shading of the lens in a direction parallel to the lens surface, more particularly, a gradually varying tint intensity on the lens, with increasing intensity in one direction and decreasing intensity in the opposite direction. Similarly, the term "gradient bleaching" is used to describe a gradient in bleaching intensity in a direction parallel to the lens surface.

[0038] The term "immersion bath" can be understood as a bath of fluid in which the lens holder, and therefore the lens, can be immersed or submerged. The immersion bath can contain, for example, a liquid in a tub or tank. The liquid can include a coloring liquid, a bleaching liquid, or any other type of liquid suitable for coloring or bleaching lenses.

[0039] The term "servo motor" may be understood as a rotary or linear actuator that allows precise control of angular or linear position, velocity, and acceleration. In general, a servo motor is understood to include a suitable motor coupled to sensors for position, velocity, and / or acceleration feedback.

[0040] The term "belt drive" should be understood as a drive including at least one belt and two pulleys, where power is transmitted between the at least two pulleys by the belt. In particular, a first pulley is configured to drive the belt, which in turn drives the second pulley. In particular, the pulley may include a shaft. Examples of belts are flat belts, V-belts and toothed belts.

[0041] The term "annular gradient" should be understood as a gradient extending in all radial directions around a center point in a plane passing through the center point. However, the gradient does not necessarily have to be the same in all directions. An annular gradient displaced from a particular point shall be understood as an annular gradient having a center point displaced from this particular point. An annular gradient can also be understood as an "annular gradient design." A partial annular gradient should be understood as a portion of an annular gradient design.

[0042] The term "pendulum gradient" should be understood as a gradient formed by the pendulum-like movement of the lens during immersion. Depending on whether the coloration or bleaching formed is symmetrical or asymmetrical with respect to the geometric center of the lens, the gradient can be classified as a "central pendulum gradient" and an "eccentric pendulum gradient".

[0043] The term "centre of gradient" in relation to annular, partial annular or pendulum tinting is to be understood as the point around which the lens must be rotated to achieve the desired gradient, i.e. the point in the lens plane where the axis of rotation is located.

[0044] The term "generally perpendicular to" should be understood as "perpendicular to" or "having a 90° angle" with a tolerance of + / -10°, preferably + / -5°, more preferably + / -2.5°, and even more preferably + / -1°.

[0045] The term "maximum rotation angle" is to be understood as the maximum angle that the lens holder can rotate (before stopping rotation and / or changing direction of rotation).

[0046] The term "maximum immersion depth" is to be understood as the deepest point of immersion (before holding the lens holder or pulling the lens holder upwards out of the immersion bath).

[0047] In one embodiment of the first method, the first method preferably further comprises displacing the receiving unit from the axis of rotation during immersion. The receiving unit, and thus the lens, may be displaced continuously or in steps, the step size being in the range of at least one of 1 mm to 20 mm, particularly 2 mm to 15 mm, particularly 3 mm to 10 mm, particularly 5 mm to 8 mm. Preferably, the lens is displaced radially from the axis of rotation.

[0048] By adjusting the displacement, the asymmetry of the lens tint can be varied. An advantage of this approach, especially when performed during immersion, is that complex tint designs can be produced in a single tinting cycle, i.e., without having to remove the lens holder from the immersion bath and / or without having to completely change the tinting apparatus. Thus, a wide variety of completely novel lens tints can be produced. Furthermore, complex lens tints can be produced faster, cheaper, and with less complexity.

[0049] In another embodiment of the first method, the lens holder is rotated in a first direction to a first position by a first predetermined angle and / or rotated in a second direction to a second position by a second predetermined angle, the first predetermined angle being different from the second predetermined angle. For example, the lens holder can be rotated 45° in a first direction and 90° in a second direction, or rotated 45° in a first direction and 45° in a second direction.

[0050] In another embodiment of the first method, the lens holder is held in a first position for a first time period and in a second position for a second time period, the first time period being different from the second time period. In this manner, the intensity of tinting or bleaching of the lens can vary in different areas of the lens.

[0051] In another embodiment of the first method, immersing the lens holder in the fluid includes moving the lens holder in a direction perpendicular to the surface of the immersion bath. Preferably, the speed and distance / depth of the lens holder movement can be adapted. For example, the lens holder can be moved a first distance, i.e., a first depth, into the immersion bath, and then moved a second distance, i.e., a second depth, different from the first distance (depth) in the opposite direction, i.e., out of the immersion bath.

[0052] In a preferred embodiment, immersing the lens holder in the fluid comprises fully or partially immersing the lens holder in an immersion bath. In particular, the receiving unit / receiving area of ​​the lens holder can be fully or partially immersed in the immersion bath by moving the lens holder. Thus, the lens (or lenses) can be fully or partially immersed in the immersion bath.

[0053] In a further preferred embodiment, the first method comprises adapting a maximum immersion depth of the lens holder into the immersion bath according to a predetermined maximum rotation angle of the lens holder.

[0054] In another preferred embodiment, the lens holder is moved in a direction perpendicular to the surface of the immersion bath by a servo motor. The use of a servo motor supports smooth and consistent movement and therefore precise tinting or bleaching of the lens.

[0055] In a further embodiment, the lens holder is rotated by a belt drive, so that the angular position of the lens can be precisely adapted, which allows for precise (angle-dependent) tinting or bleaching of the lens.

[0056] In another embodiment of the first method, the fluid comprises a liquid, in particular a tinting liquid containing a colorant configured to tint the lens or a bleaching liquid configured to bleach the lens. However, the fluid may also comprise a vapor or mist, in particular a tinting vapor configured to tint the lens or a bleaching vapor configured to bleach the lens.

[0057] In a further embodiment, the first method includes removing the lens holder from the immersion bath, either changing the fluid, displacing the lens (particularly the geometric center of the lens) relative to the rotation axis, or rotating the lens around its geometric center, and immersing the lens holder in the same or another immersion bath. Thus, the method may include two or more coloring or bleaching cycles, i.e., periods of coloring / bleaching the lens, or in other words, periods of running the coloring device. For example, the coloring liquid used in a first coloring cycle may be changed to allow a different colorant to be used in a second coloring cycle. Similarly, the lens may be positioned in a first position in a first cycle and shifted away from that position before another coloring (or bleaching) cycle.

[0058] In one embodiment of the lens, the lens comprises an ophthalmic lens, a flat glass, a monolens or a shield, in particular a helmet shield.

[0059] In another embodiment of the lens, the lens comprises a polygon, in particular a triangle or a square.

[0060] In one embodiment of the lens holder, the receiving unit of the lens holder is configured to be displaced from the rotation axis in a plane parallel to the first plane, in particular configured to be adjustably displaced, more particularly configured to be adjustably displaced by 40 mm. In another embodiment, the receiving unit of the lens holder can be displaced by up to 10 mm, in particular up to 15 mm, in particular up to 20 mm, in particular up to 30 mm, in particular up to 40 mm. In one embodiment, the receiving unit of the lens holder can be displaced by at least 5 mm, in particular at least 10 mm, in particular at least 15 mm, in particular at least 20 mm. The position of the receiving unit can be adjustable continuously or in steps, the step size being in at least one range between 1 mm and 20 mm, in particular 2 mm and 15 mm, in particular 3 mm and 10 mm, in particular 5 mm and 8 mm. Preferably, the receiving unit is configured to be displaced from the rotation axis in a radial direction.

[0061] In particular, if the displacement is performed during the tinting cycle, i.e., while the lens is immersed in the immersion bath, the lens tint design can be changed by adjusting the amount of shift, i.e., the amount of displacement. To shift, the receiving unit can include, for example, a shift element configured to shift within a so-called eccentric area of ​​the lens holder. The advantage of this approach is that complex tint designs can be produced in a single tinting cycle, i.e., without the need to remove the lens holder from the immersion bath and / or without the need to completely change the tinting device. Thus, a wide variety of entirely novel lens tints can be produced. Furthermore, complex lens tints can be produced faster, more cheaply, and with less complexity.

[0062] In another embodiment of the lens holder, the receiving unit includes a guide element configured to assist in positioning the lens in the lens holder, more particularly in the receiving area of ​​the lens holder. The guide element can be, for example, a marker such as a colored dot that marks the desired position of the lens. Similarly, the guide element can be a recess or protrusion in the receiving unit, or a bar configured to be inserted into a notch, for example, in the edge of the lens. The guide element allows for precise positioning of the lens in the lens holder and thus precise application of the tint or shade.

[0063] In a further embodiment, the lens holder includes two opposing plates, the plates being generally parallel to the first plane, and the receiving unit includes a connecting element configured to connect the plates. The connecting element may be, for example, a rod or a panel connecting the plates. Preferably, the plates are disks. More preferably, the plates include an eccentric area, and the receiving unit includes a shifting element, which can be shifted within the eccentric area.

[0064] In a preferred embodiment, the connecting element includes recesses and / or protrusions for holding the lens. For example, the connecting element may include notches or protruding clamps for gripping the lens. In this way, it can be ensured that the lens is held in a fixed position by the lens holder.

[0065] In another embodiment of the lens holder, the receiving unit is configured to hold three or more lenses. In such cases, guide elements that assist in lens positioning are particularly useful, as these guide elements can indicate the desired position and / or orientation of the lens to be tinted. Thus, a user can easily insert multiple lenses into the lens holder in the same orientation so that multiple lenses can be tinted in the same way at the same time. In particular, this allows for precise tinting effects for multiple lenses, i.e., high-precision mass production.

[0066] In one embodiment of the first coloring device, the rotation unit is configured to rotate the lens holder in a first direction by a first predetermined angle to a first position and then in a second direction by a second predetermined angle to a second position. Thus, the rotational movement of the lens holder can be performed asymmetrically. For example, the lens holder can be configured to be rotated by 90° in the first direction and by 60° in the second direction.

[0067] Preferably, the rotation unit can also be configured to adapt the rotation speed.

[0068] In another embodiment of the first tinting device, the rotation unit is configured to hold the lens holder in a first position for a first time period and in a second position for a second time period, the first time period being different from the second time period, which allows for different tinting or bleaching intensities in different areas of the lens and thus allows for completely novel tinting or bleaching designs.

[0069] In yet another embodiment of the first coloring device, the rotation unit is configured to adapt a predetermined maximum rotation angle of the lens holder according to an immersion depth of the lens holder in the immersion bath.

[0070] In a preferred embodiment of the first coloring device, the rotation unit includes a belt drive. The use of a belt drive can stabilize the rotation of the lens holder in the coloring device. However, other types of drive devices are also contemplated.

[0071] In another embodiment, the first coloring device further includes a lift unit configured to move the lens holder in a direction perpendicular to the surface of the immersion bath. The lift unit may be belt-driven. Preferably, the lift unit is configured to adjust the amount of movement, i.e., the distance or immersion depth, of the lens holder and the movement speed. For example, the lift unit may be configured to move the lens holder a first distance into the immersion bath and move the lens holder a second distance in the opposite direction, i.e., out of the immersion bath.

[0072] In a preferred embodiment of the first coloring device, the lift unit is configured to fully or partially immerse the lens holder in the immersion bath by moving the lens holder. In particular, the lift unit may be configured to fully or partially immerse the receiving area of ​​the lens holder in the immersion bath by moving the lens holder. Thus, the lift unit is configured to fully or partially immerse the lens (or lenses) held in the receiving area by the receiving unit in the immersion bath.

[0073] In yet another embodiment, the lift unit is configured to be driven by a servo motor. Similarly, the rotation unit may also be driven by a servo motor, which ensures smooth and constant linear movement or rotation, respectively.

[0074] In another embodiment, the lift unit is configured to adapt the maximum immersion depth of the lens holder into the immersion bath according to a predetermined maximum rotation angle of the lens holder. In other words, the lift unit can be configured to adapt the movement of the lens holder depending on the maximum rotation of the lens holder induced by the rotation unit. However, similarly, the rotation unit can be configured to adapt the rotation angle of the lens holder depending on the movement of the lens holder induced by the lift unit. For example, if the lens holder rotates 5° in a first direction, the lift unit can be configured to move the lens holder, which is completely above the immersion bath, toward the immersion bath so that the lens holder is immersed in the immersion bath by a first immersion depth. That is, the linear movement induced by the lift unit and the maximum rotational movement induced by the rotation unit can be related to each other.

[0075] In yet another embodiment, the coloring apparatus further comprises an agitation mechanism configured to agitate the immersion bath, the agitation mechanism ensuring uniform distribution of the coloring or bleaching liquid in the immersion bath.

[0076] Alternatively, the coloring apparatus may further include a heating element configured to heat the immersion bath.

[0077] It will be understood that the features mentioned above and those described below may not only be used in the combinations shown, but may also be used in other combinations or separately without departing from the scope of the present invention.

[0078] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. [Brief explanation of the drawings]

[0079] [Figure 1] 1 shows a flow chart of a first embodiment of a method for tinting or bleaching a lens, according to an aspect of the present invention. [Figure 2A] 1 shows a variety of lenses that can be obtained using conventional methods for tinting or bleaching lenses. [Figure 2B] 3 shows a first variety of lenses obtainable with a second embodiment of a method according to an aspect of the present invention; [Figure 3] 4 shows a second variety of lenses obtainable with a third embodiment of a method according to an aspect of the present invention. [Figure 4] 5 shows a pair of lenses obtainable using a fourth embodiment of a method according to an aspect of the invention. [Figure 5] 1 shows an embodiment of a lens holder known from the prior art; [Figure 6] 6 illustrates the lens holder embodiment of FIG. 5 with multiple lenses inserted into the lens holder. [Figure 7] 6 shows a schematic diagram of the lens in the lens holder shown in FIG. 5 after coloring. [Figure 8] 1 illustrates a first embodiment of a lens holder according to an aspect of the present invention. [Figure 9] 6 shows a schematic diagram of the lens in the lens holder shown in FIG. 5 after coloring. [Figure 10] 1 shows a perspective view of a portion of a second embodiment of a lens holder according to an aspect of the present invention; [Figure 11] 1 shows a side view of a first embodiment of a coloring device according to an aspect of the present invention; [Figure 12] 10 shows a schematic diagram illustrating the displacement of the receiving unit relative to the rotation axis of the lens holder. [Figure 13] 1 shows a perspective view of a second embodiment of a coloring device according to an aspect of the present invention; [Figure 14] 10 shows a third embodiment of a lens holder according to an aspect of the present invention. [Figure 15] 1 shows a side view of a third embodiment of a coloring device according to an aspect of the present invention. [Figure 16] 1 illustrates an exemplary gear arrangement for precisely controlled angular rotation of a lens holder in a toning device. DETAILED DESCRIPTION OF THE INVENTION

[0080] 1 shows a flowchart of a first embodiment of a method for tinting or bleaching a lens according to one aspect of the present invention. In a first step S202, a lens (or lenses) is inserted into a lens holder. The lens holder may include a conventional lens holder in which the lens is positioned so that its geometric center coincides with the axis of rotation of the lens holder, or a lens holder according to one aspect of the present invention may be used in which the geometric center of the inserted lens may be shifted away from the axis of rotation.

[0081] In a second step S204, an immersion bath containing a fluid is provided. The fluid may be, for example, a coloring or bleaching solution. The chronological order of steps S202 and S204 is irrelevant, so step S204 may be performed before step S202.

[0082] In a third step S206, the lens holder is immersed in the fluid of an immersion bath. The lens holder may be fully or partially immersed in the immersion bath.

[0083] In step S208, it is determined whether step S210 or step S212 is to be executed as the next step. This determination is based on the lens holder used. More specifically, this determination is based on the arrangement of the lens in the lens holder. If the rotation axis of the lens holder is outside the receiving unit or outside the lens, i.e., passes through the receiving area of ​​the lens, step S210 is executed. Step S210 includes adapting the maximum immersion depth of the lens holder into the immersion bath according to a (predetermined) maximum rotation angle or adapting the maximum rotation angle according to the (predetermined maximum) immersion depth of the lens holder into the immersion bath. However, if it is checked in step S208 and it is determined that the rotation axis is outside the lens in the lens holder (or outside the receiving unit), the lens holder can rotate independently of the immersion depth of the lens holder into the immersion bath (S212).

[0084] Optionally, the method of this embodiment further includes step S214, i.e., removing the lens holder from the immersion bath, changing the fluid, displacing the lens relative to the rotation axis or rotating the lens around its own geometric center, and immersing the lens holder in the same or another immersion bath.

[0085] Figure 2A shows a first variety of lenses that can be obtained using conventional methods for tinting or bleaching lenses. Figure 2A a) shows a central halo lens tint. Figure 2A b) shows a further variation of the same tint. Figure 2A c) shows a lens with an inverted central halo. These types of tints can be obtained by a method that involves partially immersing the lens in an immersion bath and rotating it through at least 360° around an axis that passes through the geometric center of the lens and is perpendicular to the lens plane.

[0086] FIG. 2B shows a first variety of lenses obtainable using a second embodiment of a method according to one aspect of the present invention. All of the lenses (and more specifically, the lens tints) shown in FIG. 2B can be obtained by a method that involves displacing the geometric center of the lens from the rotation axis of the lens holder or by using a lens holder with a receiving unit displaced from the rotation axis. The lens holder rotates at least 360°. FIG. 2B (a) shows a lens with an off-center halo tint. This type of tint can be achieved when the geometric center of the lens, particularly the lens, is located away from the rotation axis of the lens holder. Furthermore, the rotation axis can be positioned so that it lies above the surface of the immersion bath, i.e., in a parallel plane outside the immersion bath containing the colorant. In that case, when the lens holder rotates around the rotation axis, the tint design shown in FIG. 2B (a) is obtained. FIG. 2B (b) shows a lens with an inverted off-center halo. The method used can be the same as that for the lens shown in Figure 2B a), the only difference being that the axis of rotation should be in a parallel plane, but below the surface of the immersion bath, i.e., inside the immersion bath.

[0087] FIG. 2B(c) shows a pair of lenses with decentered halo tinting. The position of the halo can be precisely adjusted by fixing the lenses in the lens holder at a predefined position, specifically at a predefined distance from the rotation axis of the lens holder and at a predefined angular position relative to the geometric center of the lens. FIG. 2B(d) shows another pair of lenses with decentered halo tinting. However, in FIG. 2B(d), the halo is only partially applied to the lens. In particular, FIG. 2B(d) shows lens tinting whose gradient center is outside the lens but close to the edge of the lens. In other words, to achieve the lens shown in FIG. 2B(d), the rotation axis must be outside the lens. Different halo sizes can be obtained by adapting the immersion depth in the immersion bath and by displacing the rotation axis.

[0088] FIG. 3 shows a second variety of lenses obtainable using a method according to one embodiment of the present invention. FIG. 3a) shows a lens with a tint called "central single pendulum." This type of tint can be obtained if the rotation axis of the lens holder is located above the surface of the immersion bath, i.e., in a parallel plane outside the immersion bath, and if the lens holder rotates only about 90° in both directions. FIG. 3b) shows a lens with a tint called "central dual pendulum." This type of tint can be achieved in the same way as the tint shown in FIG. 3a), but the lens rotates 180° in the lens plane between tinting cycles. Similarly, the tint shown in FIG. 3c), i.e., "central triple pendulum" tint, can be achieved if the lens tinted as shown in FIG. 3a) is rotated 120° before another immersion in the immersion bath 104. FIG. 3d) shows a "central rectangular pendulum" tint. This type of tinting can be achieved if the tinted lens, as shown in Figure 3a), is rotated 90° in the immersion bath 104 before another tinting cycle. Thus, the lens tints shown in Figures 3b, 3c, and 3d can be achieved by an embodiment of the second method according to the present invention. Figure 3e) shows "excess pendulum tinting" as a further example of tailored tinting that can be provided by controlling immersion depth based on angular rotation. Said lens tinting can be achieved by an embodiment of the third method disclosed herein.

[0089] FIG. 4 illustrates a pair of lenses obtainable using another embodiment of the second method according to an aspect of the present invention. In this embodiment, the geometric center of the lens is shifted away from the rotation axis of the lens holder. Furthermore, in the first coloring cycle, the lens holder rotates at least 360°, while in the second cycle, the lens holder's rotation is limited to less than 360°. More specifically, the lens holder rotates less than 180° in the first direction and less than 180° in the second direction. Because the receiving unit is eccentric to obtain the coloring shown in FIG. 4 and the holder rotates like a pendulum, the coloring shown in FIG. 4 is referred to as an "eccentric pendulum halo."

[0090] 5 shows a conventional lens holder 10 configured to simultaneously tint multiple lenses. The lens holder 10 includes two opposing plates 14a and 14b connected by three rods 24a, 24b, and 24c. The three rods 24a, 24b, and 24c include a plurality of notches 28. A lens 50 to be tinted can be inserted into the rod notches and secured by a bar 26 insertable between the plates 12a and 12b. The bar 26 is configured to apply a force to the lens located in the notch, specifically to urge the lens to remain within the rod notch 28. The three rods 24a, 24b, and 24c and the bar thus form a receiving unit 20.

[0091] On the side of the plates facing away from the rods and bars, plates 14a and 14b each include a shaft 12a and 12b, respectively. The lens holder 10 can rotate about an (imaginary) axis of rotation 60 that extends through the shafts 12a and 12b. Typically, the shafts 12a and 12b are located at the geometric centers of the plates 14a and 14b. The receiving unit 20 is typically positioned such that the geometric center of the lens 50 held by the receiving unit 20 is located on the axis of rotation 60. Thus, when the lens holder 10 is rotated about the axis of rotation 60, the lens 50 inserted in the lens holder is rotated about its geometric center.

[0092] Figure 6 shows the conventional lens holder 10 of Figure 5 with a lens 50 inserted into the receiving unit 20. As can be seen, the lens 50 is gripped between the rods 24a, 24b and 24c and the bar 26. In particular, the lens is secured by the notches 28 in the rods, thereby preventing the lens from shifting.

[0093] 7A and 7B show schematic diagrams of a lens in the lens holder 10 shown in FIG. 6 after tinting. In particular, FIG. 7A shows a front view of a lens 50 inserted into a lens holder 10 including three rods 24a, 24b, and 24c and a bar 26. Tinting of the lens 50 can be achieved by a tinting procedure in which the lens holder 10 (and thus the lens 50) rotates at least 360° (or a multiple of 360°) about a rotation axis 60 while being immersed in an immersion bath at various depths. In practice, such so-called central halo tinted lenses can be produced by using a rotating lens holder 10 that reciprocates in an immersion bath such that the rotation axis 60 remains below the surface of the immersion bath throughout the tinting procedure. The tinting of the lens shown in FIG. 7A is "inverted central halo tinting."

[0094] 7B shows a front view of a lens 50 inserted into a lens holder 10 including three rods 24a, 24b, and 24c and a bar 26. The lens is tinted using a so-called central halo tint. This type of tinting can be achieved by using a lens with a solid tint in the tinting procedure as in FIG. 7A, where the immersion bath contains a bleaching solution instead of a tint. However, the same type of tinting can be achieved by using a tinting agent in the immersion bath while the rotation axis 60 of the lens holder remains above the surface of the immersion bath throughout the tinting procedure.

[0095] FIG. 8 illustrates a first embodiment of a lens holder 10 according to one aspect of the present invention. The lens holder 10 includes two opposing plates 14a and 14b connected by three rods 24a, 24b, and 24c. The three rods 24a, 24b, and 24c include a plurality of notches 28. A lens 50 to be tinted can be inserted into the rod notches and secured by a bar 26 configured to apply a force to the inserted lens, urging the lens to remain within the rod notches 28. The lens holder 10 further includes two shafts 12a and 12b on the outer sides of the plates 14a and 14b, respectively. The shafts 12a and 12b are configured to be inserted into shaft receivers of a tinting device, thereby allowing the lens holder 10 to rotate around a rotation axis 60 extending through the shafts 12a and 12b. 5 and 6, the lens holder 10 of the present invention comprises a receiving unit 20 that is shifted away from the rotation axis 60. In particular, the geometric center of the receiving area of ​​the lens is displaced relative to the rotation axis 60. More precisely, the rotation axis of the lens holder is located outside the lens (and even outside the receiving part).

[0096] 9A and 9B show schematic diagrams of a lens 50 in the lens holder 10 shown in FIG. 8 after tinting. In particular, FIG. 9A shows a front view of the lens 50 inserted into the lens holder 10, which includes three rods 24a, 24b, and 24c and a bar 26. The tint of the lens 50 in FIG. 9A reflects so-called inverted decentered halo tinting, with the center of the gradient located outside the lens but near the edge of the lens. For example, as shown in FIG. 8, inverted decentered halo tinting can be achieved by inserting a lens 50 having a solid tint into the lens holder 10 and rotating the lens holder 10 about its axis of rotation by at least 360° while partially immersing the lens holder 10 (and the lens) in an immersion bath containing a bleaching solution. A gradual shading of the tint can be achieved if the lens holder 10 moves (slightly) up and down relative to the immersion surface while rotating (shown by dashed lines).

[0097] 9B also shows a front view of lens 50 inserted into lens holder 10, which includes three rods 24a, 24b, and 24c and bar 26. The tinting of lens 50 shown is a decentered halo tint, which can be achieved by the tinting procedure applied to the lens shown in FIG. 9B, except that lens 50 is exposed to a tinting solution instead of a bleaching solution.

[0098] FIG. 10 shows a perspective view of a portion of a second embodiment of a lens holder according to one aspect of the present invention. In particular, FIG. 10 shows a receiving unit including three rods 24a, 24b, and 24c and a bar 26, with the three rods and bar connected to a shifting element 84. In this embodiment, the shifting element 84 includes a ring. The rods 24a, 24b, and 24c include notches into which the lens 50 is inserted. The bar 26 further prevents the lens 50 from falling out of the receiving unit. The fixed position is ensured by a guide element 15, which is a stick in this embodiment, extending through the notch on the edge of the lens. The ring is positioned so that its plane is perpendicular to the rods. In other words, the plane of the ring is configured to be parallel to the lens plane. The shifting element 84 (i.e., the ring) is configured to be inserted into an eccentric space 82 in the plate 14 of the lens holder.

[0099] In this embodiment, the shift element 84 is configured to shift in the eccentric space 84. In particular, the plate may include a scale indicating the amount of shift (i.e., displacement) from the rotation axis of the lens holder. For example, if the marker on the ring points to "0" on the scale, this may indicate that the receiving unit is positioned so that the rotation center of the lens holder passes through the geometric center of the receiving area surrounded by the rod and bar (and therefore the lens). On the other hand, if the marker points to "10," for example, this indicates a 10 mm offset from the center, i.e., a 10 mm shift of the geometric center of the lens from the rotation axis. Similarly, the receiving unit may rotate in the eccentric space 84 around an axis passing through the receiving area (and therefore the lens). The amount of rotation may also be indicated by a scale.

[0100] The lens holder may further include a fixing element, such as a screw, configured to fix the shift element 84 in the eccentric space 82 of the lens holder. In this embodiment, the eccentric space 82 comprises a recess in the plate 14. However, other types of eccentric spaces are also contemplated. For example, the eccentric space may be defined by a rail or the like along which the shift element 84 may move.

[0101] 11 shows a side view of a first embodiment of the second coloring device 100 according to one aspect of the present invention. In fact, only a portion of the coloring device 100 is visible in FIG. 11. In particular, the plate 14a of the lens holder 10 and the shaft 12a on the plate 14a are shown. The shaft 12a of the lens holder 10 is inserted into a receiving element of the coloring device 100. This structure allows the lens holder 10 to rotate stably by driving the shaft.

[0102] FIG. 12 shows a schematic diagram illustrating the displacement of the receiving unit 20 relative to the rotation axis of the lens holder. In this diagram, the shift element 84 is represented by a ring, and the receiving area 21 of the receiving unit, which reflects the position of the lens 50, is shown as a dashed circle. FIG. 12 particularly illustrates the displacement of the geometric center 80 of the receiving area 21 of the lens holder (and therefore the lens) relative to the rotation axis 60, which is shown to amount to 5 mm. In particular, an eccentric space 82 is shown, indicating the space within which the receiving unit 20 can move. As can be seen and is also indicated by the scale shown, the geometric center 80 of the receiving unit 20, and therefore the lens, can be shifted further away from the rotation axis 60, in particular so that the rotation axis no longer passes through the receiving area of ​​the lens holder, i.e., so that the rotation axis is outside the receiving area (i.e., when the shift element 84 is shifted to the lowest possible position). However, the receiving unit 20 can likewise shift back to a position where the geometric center 80 and the rotation axis 60 coincide.

[0103] FIG. 13 shows a perspective view of another embodiment of a second coloring device 100 for coloring a lens 50 according to one aspect of the present invention. The coloring device 100 includes a lens holder 10, an immersion bath 104, and a rotation unit 102. The lens holder 10 includes two opposing plates 14a and 14b connected by a rod 24 and a bar 26. To hold the lens 50 in a fixed position, the rod includes notches for receiving the lens, and the bar ensures that the lens remains fixed in the lens holder. In this embodiment, the rod of the lens holder 10 includes multiple notches, allowing multiple lenses to be held in the receiving area of ​​the lens holder 10. The lens holder 10 further includes shafts 12a and 12b configured to be inserted into receiving elements 106 of the coloring device 100. Thus, the lens holder 10 can rotate around an (imaginary) rotation axis 60 connecting the shafts 12a and 12b. In practice, a rotation unit 102 in the coloring device 100 is provided, which includes a belt drive 107 configured to rotate the shaft 12 a and thus the lens holder 10 around the rotation axis 60 .

[0104] The rod 24 and the bar 26 are connected at their ends to shift elements 84, which are in turn connected to the plates 14a and 14b, respectively. In particular, the shift elements can move in eccentric spaces 82, or recesses, in each of the plates 14a and 14b. The receiving unit can therefore be shifted along the surfaces of the plates 14a and 14b relative to the point where the (imaginary) axis of rotation 60 passes through the plates 14a and 14b, respectively.

[0105] In the embodiment shown in FIG. 13 , the coloring apparatus 100 further includes a lift unit 108 configured to move the lens holder 10 in a direction perpendicular to the surface of the immersion bath. The lift unit 108 can move the lens holder 10 in the same direction and / or in the opposite direction toward the bottom of the immersion bath. Thus, the lift unit 108 is configured to adjust the immersion depth in the immersion bath 104. In particular, the lift unit 108 can move the lens holder 10 while the rotation unit 102 rotates the lens holder 10. In this embodiment, the lens holder 10 can be rotated around the rotation axis 60 in a first direction to a first maximum angle while being immersed in the immersion bath to a first depth by the lift unit 108. The lens holder 10 can then rise so that it is no longer immersed in the immersion bath. In a next step, the lens holder may be rotated by the rotation unit 102 around the rotation axis 60 in a second direction to a second maximum angle while being immersed in the immersion bath to a second depth by the lift unit 108 .

[0106] By adjusting the immersion depth of the lens in the immersion bath 104 and by adjusting the rotation angle in the two rotation directions, a wide range of individual lens tints can be produced. This is even true if the tinting is modified during the tinting process, i.e., between tinting cycles, for example, by changing the color of the tint. Furthermore, instead of using a colorant in the immersion bath, a bleaching solution can be used, thereby resulting in novel bleaching effects. The tinting apparatus 100 can be used to create lenses with, for example, an off-center halo tint in a first position and an inverted off-center halo in a second position.

[0107] In this embodiment, the lift unit 108 can be driven by a servo motor 110. The use of such a motor ensures smooth movement of the lens holder 10 and therefore precise tinting of the lens.

[0108] 14 illustrates another embodiment of a lens holder 10 according to an aspect of the present invention. In this embodiment, the lens holder 10 is configured to hold a plurality of lenses, particularly more than 160 lenses. The lens holder 10 includes a rack 16 that is inserted into the coloring device 100. The rack 16 includes 16 sub-holders arranged in two rows. Each sub-holder includes two rods with notches that receive and secure a plurality of lenses 50, particularly more than 10 lenses.

[0109] 15 shows a side view of one embodiment of a coloring apparatus 100 according to one aspect of the present invention. The coloring apparatus 100 includes three lens holders 10a, 10b, and 10c partially immersed in an immersion bath 104 of the coloring apparatus 100. Lens holder 10c receives a plurality of lenses 50 to be colored.

[0110] FIG. 16 shows an exemplary gear arrangement for precisely controlled angular rotation of a lens holder in a tinting apparatus. Conventional tinting apparatuses do not require such precise angular control. The inventors have recognized that precise control of angular rotation can be provided by providing a tinting apparatus including a lens holder having a gear arrangement adapted to rotate the lens holder about a rotation axis, particularly in the context of a lift unit 108 configured to adapt the immersion depth of the lens holder 10 into the immersion bath 104 according to the rotation angle of the lens holder 10. In particular, spur gears provide precise control of angular rotation.

[0111] While the invention has been shown and described in detail in the drawings and foregoing description, such drawings and description are to be considered illustrative or exemplary and not restrictive, and the invention is not limited to the disclosed embodiments. In practicing the claimed invention, those skilled in the art can understand and effect other variations of the disclosed embodiments, from a study of the drawings, this disclosure and the appended claims.

[0112] In the claims, the term "comprises" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. A single element or other unit may fulfill the functions of several items recited in the claims. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage.

[0113] The computer program may be stored / distributed on a suitable medium, such as an optical storage medium or a solid-state medium, supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the Internet or other wired or wireless telecommunications systems.

[0114] Any reference signs in the claims should not be construed as limiting the scope.

Claims

1. 1. A method for tinting or bleaching a lens, comprising: - inserting a lens (50) into the lens holder (10); providing an immersion bath comprising a first fluid; - immersing said lens holder (10) in said first fluid; - rotating said lens holder (10) around an axis of rotation (60) up to a predetermined maximum rotation angle, said axis of rotation (60) being generally perpendicular to the plane of said lens (50); In a method comprising: The lens (50) is rotatable within the lens holder (10); The method comprises: - either rotating the lens (50) without rotating the lens holder (10) or rotating the lens (50) in the lens holder (10); - immersing said lens holder (10) in another immersion bath containing a second fluid, said first fluid and said second fluid containing a colouring or bleaching liquid; The method further comprising:

2. The method according to claim 1, further comprising displacing a receiving unit (20) that receives the lens (50) in the lens holder (10) from the rotation axis (60).

3. 1. A method for tinting or bleaching a lens, comprising: - inserting the lens (50) into the receiving unit (20) of the lens holder (10); providing an immersion bath comprising a first fluid; - immersing said lens holder (10) in said first fluid; - rotating said lens holder (10) about an axis of rotation up to a predetermined maximum rotation angle, said axis of rotation (60) being generally perpendicular to the plane of said lens (50); In a method comprising the steps of: - displacing said lens (50) and said receiving unit (20) relative to said lens holder (10) in a direction parallel to said plane of said lens with respect to said axis of rotation (60); - immersing said lens holder (10) in an immersion bath containing said first fluid or in another immersion bath containing a second fluid, said first fluid and said second fluid comprising a colouring or bleaching liquid; The method further comprising:

4. 4. The method according to claim 1, wherein the lens holder (10) is rotated in a first direction to a first position by a first predetermined angle and rotated in a second direction to a second position by a second predetermined angle, the first predetermined angle being different from the second predetermined angle.

5. 5. The method of claim 4, wherein the lens holder (10) is held in the first position for a first period of time and in the second position for a second period of time, the first period of time being different from the second period of time.

6. The method according to any one of claims 1 to 5, characterized in that immersing the lens holder (10) in the first fluid comprises moving the lens holder (10) in a direction perpendicular to a surface of the immersion bath.

7. The method according to any one of claims 1 to 6, characterized in that immersing the lens holder (10) in the first fluid comprises fully or partially immersing the lens holder (10) in the immersion bath.

8. The method according to any one of the preceding claims, further comprising adapting a maximum immersion depth of the lens holder into the immersion bath according to the predetermined maximum rotation angle of the lens holder (10).

9. Method according to any one of claims 6 to 8, characterized in that the lens holder (10) is moved in a direction perpendicular to the surface of the immersion bath by a servo motor.

10. Method according to any one of the preceding claims, characterized in that the lens holder (10) is rotated by a belt drive.

11. The method according to any one of the preceding claims, characterized in that the first fluid comprises a colouring liquid including a colouring agent configured to colour the lens (50) or a bleaching liquid configured to bleach the lens (50).

12. The method according to any one of claims 1 to 11, characterized in that the lens comprises a flat glass, a monolens or a shield.

13. The method according to any one of the preceding claims, characterized in that the lens (50) comprises a polygon.

14. A computer program comprising program code means which, when the computer program is run on a computer or processing unit, causes the computer to control a colouring device to perform any of the steps of the method according to any one of claims 1 to 13.

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