Method and apparatus for polishing spectacle lenses and molds for spectacle lens production, as well as a corresponding method for producing spectacle lenses and molds for spectacle lens production.

Abstract

Methods for polishing spectacle lenses (308a, 308b, 408a, 408b, 408c) and / or casting molds for spectacle lens production comprising the following process steps: a) Providing at least one spectacle lens (308a, 308b, 408a, 408b, 408c) with a lens surface and / or at least one mold with a mold surface b) Providing a large number of polishing bodies (310a, 310b..., 410a, 410b) with polishing body surfaces c) Generating a stochastic relative motion between the at least one spectacle lens (308a, 308b, 408a, 408b, 408c) and / or the at least one mold and the plurality of polishing elements (310a, 310b...) by means of a drive which comprises a tilting drive (304, 404) performing a tilting motion S, such that the polishing element surfaces of at least a part of the plurality of polishing elements (310a, 310b...410a, 410b...) come into abrasive contact with the lens surface of the at least one spectacle lens (308b, 408a, 408b, 408c) and / or the mold surface of the at least one mold at corresponding contact surfaces.

Description

[0001] The invention relates to a method for polishing spherical, toric and progressive spectacle lenses according to the preamble of patent claim 1, a device for polishing spherical, toric and progressive spectacle lenses according to the preamble of patent claim 6 and a method for manufacturing a spectacle lens from a semi-finished product with at least one lens surface to be machined or for manufacturing a casting mold for spectacle lens production from a spectacle lens blank with a casting mold surface to be machined.

[0002] According to the current state of the art, it is known to use flat polishing tools with a shape adapted to the surface to be treated for the polishing of spherical, toric or free-form surfaces of spectacle lenses made of mineral and organic materials.

[0003] For example, to polish the spherical surface of a spherical ophthalmic lens, a spherical, dimensionally stable polishing tool with a complementary shape is used. Due to its dimensional stability, such a polishing tool is also referred to as a forming tool. The polishing surface of the polishing tool is generally larger than the surface of the ophthalmic lens to be polished. The ophthalmic lens and polishing tool are usually driven in the same direction and at the same speed around corresponding axes of rotation and pivoted against each other in an oscillating manner during processing. Such a method can be found, for example, in DE 197 50 428 A1.

[0004] A toric, dimensionally stable, and complementary polishing tool can also be used to polish a toric surface of a toric ophthalmic lens. Instead of a rotational movement of the ophthalmic lens and polishing tool around corresponding axes of rotation, a simultaneous pivoting relative displacement occurs between the ophthalmic lens and polishing tool in the direction of the toric principal axes during polishing, thus creating an orbital relative movement between the ophthalmic lens and polishing tool while maintaining the orientation of the projections of the respective toric principal axes in a tangential plane located at the intersection of the corresponding principal axes. Such a method is described, for example, in DE 44 42 181 C1.

[0005] DE 44 42 181 C1 points out in column 9, lines 23 to 29, that this process and the corresponding polishing tool are generally suitable for polishing non-rotationally symmetrical surfaces, especially those with atoric or progressive geometries. This type of polishing or this type of polishing tool has not been established for polishing progressive or even freely formed surfaces that lack symmetry properties, because even purely translational relative movements lead to the destruction of the original surface geometry.

[0006] EP 0 835 722 A1 describes a so-called zonal polishing process for ophthalmic lenses, in which a rotary-driven, spherical polishing head with a radius of 6 mm or 10 mm is moved over a lens surface with a radius of 100 mm. Due to the point-like contact area between the polishing head and the lens surface to be polished, the process takes a comparatively long time and is therefore less economically suitable for use in polishing ophthalmic lenses.

[0007] To polish freeform surfaces of ophthalmic lenses, disc-shaped polishing tools are currently used, which provide full-surface contact with the surface to be polished. The contact area amounts to approximately 10% to 80% of the surface to be polished. Similar to the polishing of spherical surfaces, the spectacle lens and polishing tool are usually rotated around corresponding axes of rotation in the same or opposite directions and at the same or different speeds, and are pivoted against each other in an oscillating manner during processing. The polishing tool is axially displaceable and articulated in such a way that it can always follow the surface contour of the lens surface to be processed. This method and the associated device for polishing freeform surfaces are described in the publications EP 1 251 997 B2 and EP 1 386 694 B2.

[0008] To ensure that the surface of the mostly spherical tools can adapt to the geometry of the glass surface to be polished, which often deviates significantly from the spherical shape, an elastic foam layer is glued to the solid polishing tool base body, as described, for example, in DE 10 2004 003 131 A1 or DE 10 2008 062 097 A1. The polishing removal is achieved with the aid of an abrasive polishing fluid through the relative movement between the pressurised rotating polishing tool and the rotating spectacle lens. The spectacle lens is fastened to a block piece that allows it to be held in a rotating workpiece spindle. An example of this is so-called alloy blocking, which is described, for example, in DE 44 31 880 A1. State-of-the-art CNC-controlled machines are used to implement the relative movement between the polishing tool and the workpiece.

[0009] Although the polishing process and the polishing tool described above have proven to be effective, there is still room for improvement in many respects.

[0010] It was discovered that the polishing tools used do not adapt to every surface geometry of the lens being processed. This non-ideal adaptation of the polishing tools results in an uneven pressure distribution on the lens surface, which in turn is associated with an uneven material removal distribution on the lens surface. The resulting form error increases with increasing deviation from sphericity. This limits the range of polishable lens geometries.

[0011] The need for CNC-controlled polishing machines makes polishing complex and therefore costly.

[0012] A clamping device is required for lens positioning and rotation. In ophthalmic lens manufacturing, this is achieved by blocking with alloy, cementing, or gluing to a block piece. Block-free processing is therefore not possible. On the one hand, the blocking process itself is time-consuming, and on the other, it would be desirable to eliminate the environmentally harmful materials required for blocking.

[0013] The fundamental disadvantage of current polishing processes is that the elastic layer of the spherical or toric polishing tool must completely compensate for the height differences of the surface area currently covered by the lens, which are caused by the toric or freeform geometry of the lens. These height differences can easily be in the range of several millimeters for today's standard progressive lens surfaces equipped with a toric component. Therefore, the pressure distribution on the lens surface is not constant during the polishing process.

[0014] Due to the proportionality of locally applied polishing pressure and the resulting material removal rate, this polishing process inherently results in form defects, the size of which depends on the degree of asphericity of the ophthalmic lens. Furthermore, precisely defined polishing movements are necessary, which must be determined depending on the ophthalmic lens parameters such as diameter, surface curvature, etc., as well as the tool parameters such as tool diameter, tool stiffness, etc.

[0015] With these polishing processes, lenses are processed individually, meaning each lens is assigned a separate polishing station. Because a job in ophthalmic lens production typically consists of one lens for the wearer's right eye and one for the wearer's left eye, the machines used often have two polishing stations for paired processing. According to the current state of the art, the lens and / or polishing tool must be CNC-controlled in terms of rotation and pivot position throughout the entire process, which requires correspondingly complex, technically sophisticated, and therefore expensive polishing machines.

[0016] Another disadvantage of conventional processing technology is that the lens's protrusion above the block must be minimal to prevent this area from deforming or even breaking under the applied compressive stress. This factor is particularly important for thin ophthalmic lenses or those with thin edges, limiting the applied polishing pressure and thus the efficiency of the entire polishing process. This, in turn, is associated with high costs.

[0017] Also limited by current technology are the smallest diameter that can be polished and the maximum deviation from the circular shape (difference between the smallest and largest radius) for elliptical or free-form edges.

[0018] A further disadvantage of conventional polishing is that circumferential polishing defects can occur in the edge zone. These defects are caused by wave-like deformation of the polishing coating due to varying compression values ​​of the tool as it passes over the edge of the lens. This impairs the optical quality in the edge area of ​​the lens and limits the optically usable area. This defect is known as edge wave.

[0019] US Pat. No. 3,030,746 A discloses a method for polishing optical glass, such as condenser lenses. The condenser lenses are placed in a rotating drum together with a liquid and abrasive media, such as ceramic truncated cones or similar.

[0020] DE 10 2011 113 167 A1 discloses a method for surface treatment of workpieces, such as optical lenses, in which the workpiece is immersed in a bed of polishing granules contained in a container and moved relative to the bed of polishing granules. The container is rotated about a vertical axis.

[0021] JP 2009-269094 A discloses a method and apparatus for manufacturing optical elements made of glass, such as a lens. The method includes grinding the optical elements using a drum polisher. The drum polisher includes a vibration generator.

[0022] US 3 589 071 A discloses an apparatus and method using ultrasonic vibrations and a polishing slurry for fine polishing of lenses.

[0023] JP H08-243 902 A discloses a method and system for finishing an optical glass element. The method comprises a housing vessel in which the optical glass element is fixed, and an alkaline solution and abrasive grain are injected into the housing vessel.

[0024] According to the state of the art known within the company, a spectacle lens is manufactured from a prefabricated or semi-finished product with at least one lens surface to be machined using the following sequential process steps: a) Protection of the side of the prefabricated product facing a block piece with protective varnish or protective film against damage b) Fixing the prefabricated product to the block piece using alloy, adhesive or putty material c) Shaping of the lens surface by grinding, milling and / or turning d) Polishing of the surface shaped under c) e) Applying reference marks in the form of reference engravings, reference notches or the like f) Separating the semi-finished product created from the prefabricated product from the block piece g) Cleaning the semi-finished product h) Protection of the optically finished side of the semi-finished product by means of protective varnish or protective film i) Fixing the semi-finished product, if necessary aligned and oriented according to the reference marks provided under e), using alloy, adhesive or putty material on a block piece j) Shaping of the lens surface facing away from the block piece by grinding, milling and / or turning k) Polishing of the surface shaped under j). l) Applying reference marks in the form of reference engravings, reference notches or the like m) Separating the spectacle lens made from the semi-finished product from the block piece n) Cleaning the lens o) Optional coating of the lens on one or both sides p) Position-oriented blocking of the spectacle lens for positioning during the subsequent grinding process q) Grinding the lens into the frame

[0025] The process sequence of double-sided machining described here is reduced to one-sided machining using steps h) to j) if the semi-finished product is manufactured in another way, for example by casting.

[0026] In particular, the grinding process requires precise blocking after the hard and anti-reflective coating for the grinding process, with the associated difficulties such as precise positioning and alignment of the block piece, ensuring sufficient adhesion regardless of the respective coating, and avoiding damage to the coating during blocking.

[0027] The object of the invention is therefore to provide a more cost-effective and more widely applicable polishing process, a corresponding device for polishing spectacle lenses or casting molds and a simplified method for manufacturing a spectacle lens from a semi-finished product with a lens surface to be machined or a casting mold from a casting mold blank with a casting mold surface to be machined.

[0028] This object is achieved by a method having the features of claim 1, by a device having the features of patent claim 6, and by a method for manufacturing a spectacle lens from a semi-finished product with at least one lens surface to be machined or from a blank with two optical active surfaces to be machined or a casting mold from a casting mold blank with one casting mold surface to be machined, having the features of patent claim 15. Advantageous embodiments and further developments of the invention are the subject of the dependent claims.

[0029] The main idea of ​​the invention is to completely abandon the previously common, large, elastic polishing tools adapted to the shape of the ophthalmic lens surface, rotating spindles, the associated specific relative movements required, and the application of pressure over a wide area. Instead, it uses a multitude of comparatively very small polishing tools, referred to below as polishing bodies, which can adapt to any surface, no matter how complex. A random relative movement with random orientation is generated between the workpiece and the polishing body, resulting in a polishing removal on the ophthalmic lens surface.

[0030] The method according to the invention for polishing spectacle lenses comprises the following process steps: a) Providing at least one spectacle lens with at least one lens surface to be polished b) Providing a variety of polishing bodies with polishing body surfaces c) generating a stochastic, i.e. random, relative movement between the at least one spectacle lens and the plurality of polishing bodies by means of a drive which comprises a tilting drive, so that the polishing body surfaces of at least a part of the plurality of polishing bodies come into abrasive contact with the surface of the at least one spectacle lens at corresponding contact surfaces.

[0031] This process allows for all-round polishing of all unprotected surfaces, including edges, corners, etc.

[0032] This process can be used to produce high-quality polished ophthalmic lens surfaces, regardless of the material the lenses are made of. The ophthalmic lenses can be made of an organic or a mineral material. Typical organic materials are diethylene glycol diallyl carbonate or allyl diglycol carbonate (abbreviation: ADC), which is marketed by PPG Industries under the brand name "Columbia Resin 39" or "CR 39", higher-refractive thermosetting polymer materials such as the polythiol urethanes marketed by Mitsui Chemicals under the trade names MR-7, MR-8, and MR-10 (the abbreviation "MR" stands for Mitsui Resin), polymethyl methacrylate (abbreviation: PMMA), or polycarbonate. Mineral materials are divided into crown glasses (Abbe number >55) and flint glasses (Abbe number <50).

[0033] The process is suitable for the sequential polishing of individual spectacle lenses or for the simultaneous parallel polishing of several or a large number of spectacle lenses.

[0034] During polishing, the lens and polishing body do not come into contact over a large area, but rather at points. The contact areas between the lens and polishing body are approximately between 0.1 mm 2 and 25 mm 2 , preferably between 0.2 mm 2 and 5 mm 2 Due to the large number of polishing media used, which come into abrasive contact with a spectacle lens almost simultaneously, the process is also referred to as multipoint polishing.

[0035] The pressure and kinetic energy required for mechanical surface abrasion is introduced in the form of vibrations. Vibration (or oscillation) is understood here as the relative change in motion between the lens and the polishing body when a disturbance disrupts the stable equilibrium of the lens and polishing body system, and a restoring force propels it back to its initial state and then beyond it.

[0036] Viewed from the lens, the polishing particles can, for example, repeatedly rub against each other, bounce, dance, rotate, etc., i.e., perform any abrasive relative movement. The relative movement can therefore be not only oscillatory, but also rotational and / or translational.

[0037] The frequencies of the oscillations are preferably in a range between 1 Hz and 20 kHz. Oscillatory movements with a frequency between 1 Hz and 10 kHz are advantageous, preferably between 10 Hz and 5 kHz, most preferably between 20 Hz and 2 kHz. For the same reason, the rotational speed of the rotational movement is advantageously between 1 revolution per minute and 10,000 revolutions per minute, preferably between 10 revolutions per minute and 5,000 revolutions per minute, most preferably between 20 revolutions per minute and 2,000 revolutions per minute. The translational relative movement occurs, for example, at a relative speed between 0.01 m / s and 10 m / s, preferably between 0.1 m / s and 8 m / s, most preferably between 0.2 m / s and 5 m / s.

[0038] In contrast to conventional polishing methods known from the prior art, in which a polishing body and / or the spectacle lens is / are subjected to a rotational or orbital movement to achieve uniform surface removal, the method according to the invention, due to the intermittent, multipoint abrasive contact between the spectacle lens and the polishing bodies, requires a non-directional relative movement. The temporally stochastic abrasion leads, on average, to a substantially homogeneous polishing removal across the entire spectacle lens surface if the method according to the invention is carried out for a sufficient duration.

[0039] This type of polishing generally allows for the removal and smoothing behavior, as well as the resulting surface roughness, to be controlled across a wide range by appropriately varying the polishing media material, its shape, the type of movement applied, and the type and amount of polishing suspension added. The particular advantage of this process for ophthalmic lens production is that the geometry of the ophthalmic lens(es) now plays a subordinate role, and no form defects arise due to different removal rates in the various zones of the ophthalmic lens surface(s).

[0040] The removal process itself can be carried out either dry or with the addition of a suspension that supports the desired effect on the workpiece surface. For the processing of plastic ophthalmic lenses, an example is a commercially available polishing suspension with a suitable proportion of Al2O3 particles. Due to its chemical properties, this suspension conditions the workpiece surface to be processed and thus supports the polishing process in such a way that the desired optical criteria regarding roughness and uniformity are achieved.

[0041] The device for polishing spectacle lenses according to the method described above comprises a) a holder for at least one spectacle lens with at least one lens surface to be machined, b) a variety of polishing bodies with polishing body surfaces and c) a drive for generating a stochastic relative movement between the at least one spectacle lens and the plurality of polishing bodies, which drive comprises a tilting drive, so that the polishing body surfaces of at least a part of the plurality of polishing bodies come into abrasive contact with the surface of the at least one spectacle lens at corresponding contact surfaces.

[0042] A comparatively simple construction of the device according to the invention results if the receptacle comprises a container into which the at least one spectacle lens and / or the plurality of polishing bodies can be introduced. The container can be a drum, similar to the drum of a washing machine, into which at least one spectacle lens and a plurality of polishing bodies are placed. This drum, like the drum of a washing machine, can be rotationally driven by a motor to generate a stochastic relative movement between the at least one spectacle lens and the plurality of polishing bodies.

[0043] The inner wall of the drum can be coated with a non-abrasive material to protect the lens(es) from damage and / or scratching. It is also possible for the inner wall of the drum itself to be coated with an abrasive material that produces a polishing effect. In particular, it is possible for the plurality of polishing bodies to be secured to the inner wall, and for the lens(es) to move freely along the inner wall due to the rotation of the drum, similar to laundry in a washing machine drum.

[0044] Finally, it is possible that a large number of polishing media in the drum, together with the lens(es), move freely due to the rotation of the drum and stochastically come into abrasive contact with the surfaces of the lens(es). Incorporated baffles and / or a spiral design of the inner wall of the container can positively influence the mixing and relative movement between the polishing media and the lens.

[0045] In general, the container can be designed such that the at least one spectacle lens is freely movable within the at least one container and / or that the plurality of polishing bodies is freely movable within the container. Tests with plastic spectacle lenses have shown that multiple spectacle lenses can also be located in the container, which is driven to generate a stochastic relative movement between the spectacle lenses and the plurality of polishing bodies, without scratching or damage to the spectacle lenses, which would impair their optical quality. Contact between the spectacle lenses therefore does not lead to any relevant abrasive removal, whereas contact between the spectacle lens and the polishing body causes abrasive removal.

[0046] The receptacle can comprise a holding device for releasably securing the at least one spectacle lens. In the example of the drum, for example, corresponding holding devices for the spectacle lenses can be provided on the inner wall. When the drum is set in rotation, the plurality of polishing bodies moves over the lens surfaces. Holding devices for releasably securing spectacle lenses are preferably used when there is a risk that the surfaces of the spectacle lenses could be damaged upon contact with other spectacle lenses. This variant is therefore particularly suitable for use in polishing mineral spectacle lenses.

[0047] In the context of this invention, a plurality of polishing bodies is understood to mean a number greater than 100, for example greater than 500, preferably greater than 1000, most preferably greater than 2000. If several or even a large number of spectacle lenses are subjected to the polishing process simultaneously in a device according to the invention, it is advantageous if this number of greater than 100, greater than 500, greater than 1000 or greater than 2000 indicates the ratio between the number of polishing bodies used and the number of spectacle lenses processed.

[0048] The polishing bodies can be made of a material with a ceramic material, a material with a plastic material, or a material containing both a ceramic material and a plastic material. In the latter case, the ceramic material can be embedded in the plastic material in granular form, or vice versa. It is also possible for the plastic material to form a core coated with a ceramic material, or for a ceramic core to be coated with a plastic coating. The polishing bodies can also be made of metallic, organic, or biological / natural materials.

[0049] The polishing bodies can also consist of composite materials, in particular of the materials mentioned above.

[0050] It has been shown that very good polishing results are achieved when the plastic material is polyurethane. This plastic material is characterized by its good abrasiveness and moderate hardness.

[0051] For polishing progressive spectacle lenses, it has proven effective if the polishing bodies have a volume between 5 mm 3 and 10000 mm 3 , preferably between 10 mm 3 and 5000 mm 3 , most preferably between 100 mm 3 and 10000 mm 3 Such polishing body volumes ensure that the abrasive contact between the spectacle lens and the polishing body is sufficiently small, i.e., punctiform, and that material removal occurs even at the deepest points of the spectacle lens surface.

[0052] The mass of a polishing body is preferably between 10 mg and 50 g, most preferably between 1 g and 10 g. A lower mass results in insufficient polishing pressure for material removal.

[0053] As already outlined above by way of example, the drive for generating the relative movement between the spectacle lens and the polishing bodies can be or comprise a rotating drum.

[0054] The limitations of ophthalmic lens geometry mentioned in the introduction to the description are completely eliminated with "multi-point polishing," and significantly more complex geometries can now be polished. It is also now possible to polish ophthalmic lenses that have been manufactured to their final contour prior to the polishing process. This allows the entire machining process, such as pre-milling, turning, edging, and, if necessary, drilling, to be performed entirely in a single setup prior to polishing. This enables significantly greater positioning accuracy from design to edge contour or frame geometry. Following the hard and anti-reflective coating, re-blocking for the grinding process, with its associated difficulties such as precise positioning of the block piece, varying and sometimes inadequate adhesion to different coatings, twisting errors, etc., can be completely eliminated.For the coating processes, this means that, since the spectacle lenses are already manufactured to the frame contour, significantly smaller workpieces generally need to be coated, which has a positive effect on coating capacity, for example. Thus, for example, the following process for manufacturing an spectacle lens from a semi-finished product with a lens surface to be machined is possible according to the invention, which is significantly simplified compared to the prior art: a) Protection of surfaces not to be machined, in particular the side of the semi-finished product facing a block piece, with protective varnish or protective film against damage b) Fixing the semi-finished product to a block piece using alloy, adhesive or putty material c) Shaping of the lens surface by grinding, milling and / or turning d) Edge machining of the shaped spectacle lens and / or grinding of the shaped spectacle lens and / or drilling of the shaped spectacle lens e) individual marking of the spectacle lens, whereby this step can optionally be carried out before steps a) or b) or c) or d) f) Covering surfaces that are not to be polished with suitable protective varnish, foil or the like g) Polishing the individually marked spectacle lens using the method described above h) Cleaning i) Coating and / or dyeing j) Sorting based on customer orders, whereby this step can optionally be carried out before step h) or i).

[0055] It should be noted that this sequence of process steps merely specifies the sequence in which the manufacturing process is carried out. However, it is fundamentally possible for additional intermediate steps to be performed between the individual process steps, or for individual process steps to be omitted. In particular, process steps a), d), e), h), i), and j) are optional.

[0056] A key prerequisite for the cost-effective application of this manufacturing process is the unique identifiability of each individual lens, since the polishing process presented here eliminates the need for paired processing. This can be achieved, for example, by individually laser-marking the lens (dot matrix code, order number, etc.) or by any other type of marking that is still legible after the aforementioned multi-point polishing process.

[0057] Because the ophthalmic lens can be machined to its final edge geometry during the shaping process, and complex geometries are also permitted during polishing, the ophthalmic lens edge geometry can be supplemented with additional contour elements that perform positioning and holding functions, for example, in the downstream coating process. Furthermore, the identifying marking can be applied to these additional contour elements, so that the actual ophthalmic lens is not affected by the marking.

[0058] A predetermined breaking point between the finished lens and this additional contour element makes separation easier.

[0059] Instead of a spectacle lens, a mold for producing spectacle lenses can also be polished using the polishing method according to the invention described above. Instead of the lens surface, the corresponding mold surface is polished.

[0060] In a corresponding manner, the device according to the invention can be configured for polishing a casting mold, alternatively or additionally. In this case, the holder must be designed to accommodate the casting mold(s), and the drive must be dimensioned accordingly to generate a corresponding relative movement between the casting mold(s) and the polishing body.

[0061] Finally, according to the invention, the last-described manufacturing method comprising process steps a) to j) is used to produce casting molds.

[0062] The invention is described in more detail below with reference to the drawings. They show: Fig. 1 a first embodiment of a device for polishing spectacle lenses Fig. 2 a second embodiment of a device for polishing spectacle lenses Fig. 3 a first embodiment of an apparatus according to the invention for polishing spectacle lenses Fig. 4 a second embodiment of a device according to the invention for polishing spectacle lenses

[0063] The Fig. Figure 1 shows a first embodiment of a device 100 for polishing spectacle lenses 108a, 108b. This device 100 comprises a drum 102, a motor 104, and a shaft 106 that connects the motor 104 and drum 102 in a manner that transmits a torque. The common center axis 106a of the drum 102, shaft 106, and motor 104 is arranged inclined relative to the horizontal. However, it could also be arranged vertically, as in the embodiment according to Fig. 2 be arranged.

[0064] Located in the drum are several spectacle lenses 108a, 108b and a plurality of polishing bodies 110a, 110b, 110c, 110d, ...110n in the form of cylindrical polyurethane rods with a diameter of 1.5 mm, a length of 5 mm, and a mass of approximately 1 g. The spectacle lenses 108a, 108b and the plurality of polishing bodies 110a, 110b, 110c, 110d, ...110n are freely movable in the drum 102.

[0065] The motor 104 drives the inclined drum 102 in a rotational R manner via the shaft 106. This creates a stochastic relative movement between the spectacle lenses 108a, 108b and the plurality of polishing bodies 110a, 110b, 110c, 110d, ...110n, so that the polishing body surfaces of at least some of the plurality of polishing bodies 110a, 110b, 110c, 110d, ...110n come into abrasive contact with the surface of the spectacle lenses 108a, 108b at corresponding contact surfaces.

[0066] The removal process itself can be carried out either dry or with the addition of a polishing suspension. For processing plastic ophthalmic lenses, a polishing suspension containing Al2O3 particles can be used. It has been shown that several ophthalmic lenses can be polished simultaneously without the need to fix them within the drum 102, so as not to touch each other in a way that would negatively affect the polishing result. The inner wall of the drum 102 is designed to prevent damage to the lenses and to prevent any removal during the contact time between the ophthalmic lens and the inner wall, which would negatively affect the polishing result.

[0067] The Fig. Figure 2 shows a second embodiment of a device 200 for polishing spectacle lenses 208. This device 200 again comprises a drum 202, a motor 204, and a shaft 206 that connects the motor 204 and drum 202 in a way that transmits torque. The common center axis 206a of the drum 202, shaft 206, and motor 204 is arranged at an angle. However, it could also be arranged vertically or horizontally.

[0068] In the drum there is at least one spectacle lens 208a, 208b, 208c and a plurality of polishing bodies 210a, 210b, 210c, 210d, ..., 2101, 210m, 210n of the aforementioned type. The plurality of polishing bodies 210a, 210b, 210c, 210d, ..., 2101, 210m, 210n are freely movable in the drum 202, as is the at least one spectacle lens 208a, 208b, 208c. In extension to the Fig. In the embodiment shown in Figure 1, additional guide contours 216, e.g. in the form of guide plates, screw profiles, etc., are introduced into the drum 202 in order to positively influence the mixing, wherein the relative movement of polishing bodies and spectacle lenses continues to be characterized stochastically.

[0069] According to the embodiments shown, the motor 204 drives the inclined drum 202 in rotation R via the shaft 206. The freely movable polishing bodies 210a, 210b, 210c, 210d, ..., 210l, 210m, 210n and the spectacle lenses 208a, 208b, 208c are conveyed upwards via a screw 216 and fall down in the middle at the end. This creates a stochastic relative movement between the spectacle lenses 208a, 208b, 208c and the plurality of polishing bodies 210a, 210b, 210c, 210d, ..., 210l, 210m, 210n, so that the polishing body surfaces of at least some of the plurality of polishing bodies 210a, 210b, 210c, 210d, ..., 210l, 210m, 210n come into abrasive contact with the surfaces of the spectacle lenses 208a, 208b, 208c at corresponding contact surfaces and polish them multipointly.

[0070] In the case of a helical design of the wall, a continuous process with continuous forward movement of the contents is also possible due to the initiated rotational movement of the drum 202 around the central axis 206a.

[0071] The Fig. Figure 3 shows a first embodiment of an apparatus 300 according to the invention for polishing spectacle lenses 308a and 308b. This apparatus 300 comprises a container 302, a tilting drive 304, and a plurality of coil springs 306a, 306b that connect the tilting drive 304 and the container 302 in a manner that transmits vibrations. The center axis 306c of the drum 302 is arranged vertically in the embodiment. However, it could also be inclined, as in the embodiment according to the Fig. 1 or arranged horizontally. Alternatively, the coil springs can be replaced with a different type of spring element.

[0072] In the container 302, there are several spectacle lenses 308a and 308b and a plurality of polishing bodies 310a, 310b, 310c, 310d, 310e, 310f of the aforementioned type. The plurality of polishing bodies 310a, 310b, 310c, 310d, 310e, 310f and the spectacle lenses 308a, 308b are freely movable in the container 302. It is possible, as in the embodiment according to the Fig. 4 one or more holders shall be provided to fix a corresponding number of spectacle lenses.

[0073] According to the invention, the tilting drive 304, which executes a tilting movement S, drives the container 302 in a translational oscillation T1, T2. The pressure and kinetic energy required for mechanical abrasion of the surface is introduced here in the form of vibrations, whereby the entire system of spectacle lenses 308a and 308b / polishing bodies 310a, 310b, 310c, 310d, 310e, 310f is subjected to vibrations. Due to their different mass compared to the spectacle lenses 308a, 308b, the polishing bodies 310a, 310b, 310c, 310d, 310e, 310f perform a relative movement to the latter.

[0074] The Fig. Figure 4 shows a further embodiment of a device 400 according to the invention with container 402, tilt drive 404 and coil springs 406a, 406b, which is characterized in that the at least one spectacle lens 408a, 408b, 408c to be polished is fixed with a holder 412. By means of this holder 412, which in the present example is designed like a mobile with a carrier 412a and rods 412b, 412c, 412d for fastening the spectacle lenses 408a, 408b, 408c, on the one hand, contact between the spectacle lenses 408a, 408b, 408c is prevented and on the other hand, it also enables the spectacle lenses 408a, 408b, 408c to be guided in a targeted manner on a rotational and / or translational path movement through the polishing bodies 410a, 410b, 410c which are in stochastic movement.This advantageous guided movement of the spectacle lens 408a, 408b, 408c by the polishing bodies 410a, 410b, 410c is not absolutely necessary, provided that a homogeneous distribution of the pressure and kinetic energy sufficient for mechanical abrasion on the spectacle lens surface can be achieved by the vibrations transmitted to the container 402 via the tilt drive 404 and helical springs 406a and 406b.

[0075] Instead of the tilting drive shown, a vibrator or other vibration generator can also be used, which causes the container 402 to vibrate in such a way that the polishing bodies cause an abrasive and smoothing effect on the surface of the workpieces through relative movements.

[0076] As an alternative to the tilting movement shown, a rotational movement of the container 402 is also possible as in Fig. 1 and Fig. 2, as well as a completely stationary container 402 and the sole introduction of the stochastic relative movement between polishing bodies 410a, 410b, 410c... and spectacle lenses 408a, 408b, 408c by a movement introduced via the holder 412, which in the present case has both rotational and translational components, which in Fig. 4 are identified by the reference symbols R1, R2, R3, R4, R5 and T1, T2, T3, T4.

[0077] With the aforementioned multi-point polishing process, several dozen ophthalmic lenses can be processed simultaneously in one container. After the process, vibrating devices and sieves can be used to separate polishing media and any liquids or suspensions used to support the process from the lenses, allowing them to be recycled into the polishing process. List of reference symbols 100, 200, 300, 400 device 102, 202 drum 104, 204 engine 106, 206 wave 106a, 206a, 306c center axis 108a, 108b, 208, 208a...208c, 308a, 308b, 408a...408c glasses lenses 110a...110n, 210a, ... 210n, 310a..310f, 410a...410c polishing bodies 216 leading contours / snail 302, 402 containers 304,404 Tilt drive 306a, 306b, 406a, 406b coil springs 412 bracket 412a carrier 412b, 412c, 412d Bars R Rotation R1, R2, R3, R4, R5 rotary components S Tilting movement T1, T2, T3, T4 translational components

Claims

[1] Method for polishing spectacle lenses (308a, 308b, 408a, 408b, 408c) and / or casting molds for spectacle lens production, comprising the following process steps: a) providing at least one spectacle lens (308a, 308b, 408a, 408b, 408c) with a lens surface and / or at least one mold with a mold surface b) Providing a plurality of polishing bodies (310a, 310b..., 410a, 410b) with polishing body surfaces c) generating a stochastic relative movement between the at least one spectacle lens (308a, 308b, 408a, 408b, 408c) and / or the at least one casting mold and the plurality of polishing bodies (310a, 310b...) by means of a drive which comprises a tilting drive (304, 404) which executes a tilting movement S, so that the polishing body surfaces of at least some of the plurality of polishing bodies (310a, 310b...410a, 410b...) come into abrasive contact with the lens surface of the at least one spectacle lens (308b, 408a, 408b, 408c) and / or the casting mold surface of the at least one casting mold at corresponding contact surfaces. [2] Method according to claim 1, characterized by that the contact surfaces are between 0.1 mm 2 and 25 mm 2 , or between 0.2 mm 2 and 5 mm 2 are large. [3] Method according to one of the preceding claims, characterized bythat the relative movement is an oscillatory movement and / or a rotational movement and / or a translational movement. [4] Method according to one of the preceding claims, characterized by that the oscillatory movement occurs at a frequency between 1 Hz and 10 kHz, or between 10 Hz and 5 kHz, or between 20 Hz and 2 kHz and / or that the rotational movement occurs at a rotational speed between 1 revolution / minute and 10,000 revolutions / minute, or between 10 revolutions / minute and 5,000 revolutions / minute, or between 20 revolutions / minute and 2,000 revolutions / minute and / or that the translational relative movement occurs at a relative speed between 0.01 m / s and 10 m / s, or between 0.1 m / s and 8 m / s, or between 0.2 m / s and 5 m / s. [5] Method according to one of the preceding claims, characterized by that the relative movement is an undirected movement. [6] Device for polishing spectacle lenses (308a, 308b, 408a, 408b, 408c) and / or casting molds for spectacle lens production a) with a receptacle for at least one spectacle lens (308a, 308b, 408a, 408b, 408c) with a lens surface and / or for at least one casting mold with a casting mold surface, b) with a plurality of polishing bodies (310a, 310b...410a, 410b...) with polishing body surfaces, c) with a drive (304, 404) which comprises a tilting drive (304, 404) which executes a tilting movement S, for generating a stochastic relative movement between the at least one spectacle lens (308a, 308b, 408a, 408b, 408c) and / or the at least one casting mold and the plurality of polishing bodies (310a, 310b...410a, 410b...), so that the polishing body surfaces of at least some of the plurality of polishing bodies (310a, 310b...410a, 410b...) come into abrasive contact with the lens surface of the at least one spectacle lens (308a, 308b, 408a, 408b, 408c) and / or with the casting mold surface of the at least one casting mold at corresponding contact surfaces. [7] Device according to claim 6, characterized by that the receptacle comprises a container into which the at least one spectacle lens (308a, 308b, 408a, 408b, 408c) and / or the plurality of polishing bodies (310a, 310b...410a, 410b...) can be introduced. [8] Device according to claim 7, characterized bythat the container is designed such that the at least one spectacle lens (308a, 308b) is freely movable in the at least one container (302, 402) and / or that the plurality of polishing bodies (310a, 310b...410a, 410b...) is freely movable in the container (302, 402). [9] Device according to one of claims 6 to 7, characterized by that the receptacle comprises a holding device (412) for releasably fastening the at least one spectacle lens (408a, 408b, 408c). [10] Device according to one of claims 6 to 9, characterized by that the plurality is a number greater than 1, or greater than 50, or greater than 100, or greater than 200. [11] Device according to one of claims 6 to 10, characterized bythat the polishing bodies (310a, 310b...) consist of a material comprising at least one of the following materials: a ceramic material, a plastic material, a metallic material, an organic material, a biological and / or natural material. [12] Device according to claim 11, characterized by that the plastic material is polyurethane. [13] Device according to one of claims 6 to 12, characterized by that the polishing bodies (310a, 310b...410a, 410b...) have a volume between 5 mm 3 and 10000 mm 3 , or between 10 mm 3 and 5000 mm 3 , or between 100 mm 3 and 1000 mm 3 have. [14] Device according to one of claims 6 to 13, characterized by that the drive comprises a rotating drum. [15] Method for manufacturing a spectacle lens from a semi-finished product with a lens surface to be machined or for manufacturing a casting mould for the production of spectacle lenses and a casting mould blank with a casting mould surface to be machined, comprising the following successive process steps: a) Optional protection of non-machined surfaces of the semi-finished product or the casting mold blank with protective varnish or protective film against damage, b) Fixing the semi-finished product or the casting mold blank to a block piece using alloy, adhesive or putty material, c) Shaping of the lens surface or the casting mould surface by grinding, milling and turning, d) Optionally, edge machining of the shaped spectacle lens and / or grinding of the shaped spectacle lens and / or optionally drilling of the shaped spectacle lens, e) Optional individual marking of the lens or the mould, whereby this step can optionally be carried out before steps a) or b) or c) or d), f) Covering surfaces not to be polished with protective varnish or film, g) polishing the individually marked spectacle lens using the method according to one of claims 1 to 5, h) Optionally clean, i) Optional coating and / or optional coloring, j) Optionally sort based on customer orders, whereby this step can optionally be carried out before step h) or i).

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