Device for polishing an optical lens or an optical mirror and method for polishing an optical lens or an optical mirror

Abstract

The invention relates to a device for polishing an optical lens or an optical mirror with a liquid polishing agent, wherein the device comprises a workpiece carrier for fixing at least one first surface of the optical lens or the optical mirror, wherein the workpiece carrier has a porous and elastic support for fixing the at least one first surface of the optical lens or the optical mirror, and wherein the support is designed as a surface permeable to the polishing agent. Furthermore, the invention relates to a method for polishing an optical lens or an optical mirror.

Description

[0001] The invention relates to an apparatus for polishing an optical lens or an optical mirror and a method for polishing an optical lens or an optical mirror.

[0002] For the sake of simplicity, the following text refers to lenses. However, optical mirrors with an imaging function are also always meant.

[0003] In practice, optical lenses are manufactured from transparent materials through multiple grinding processes or other machining methods. These materials can be mineral glass or suitable plastics.

[0004] In practice, optical lenses are manufactured from blanks in several steps. The grinding process is followed by polishing, which smooths the surface. Grinding typically involves using so-called cup tools, which perform rough and fine grinding. These tools have a diamond coating on their cutting edge, which can be coarser or finer depending on the grinding process to be performed.

[0005] In practice, polishing with appropriate polishing machines, however, is performed using tools whose surfaces are made of a relatively soft material. In one possible embodiment, the surface of the polishing tool in the working area is covered with a soft PU (polyurethane) film, known as a polishing film. Material removal is ensured by a polishing suspension that is introduced into the working area during the polishing process. It contains extremely fine particles that ensure the desired material removal. There are also polishing suspensions that can also remove material chemically.

[0006] In practice, it is known to form the base body of the polishing tool from a solid material. The base body has a shape in the working area that roughly corresponds to the negative impression of the surface of the lens to be polished. This area of ​​the polishing tool is covered with the aforementioned polishing film, which is then very precisely dressed using a dressing tool. After the dressing process, the surface of the polishing film corresponds very precisely to the negative impression of the optical lens. Such polishing tools are referred to as forming tools. However, polishing tools have also become known whose surface in the working area is made of a material that has the properties of a polishing film, meaning that an additional polishing film is not required.

[0007] As is known from practice, the polishing tool is attached to a tool spindle of a polishing machine, which sets it in rotation. The lens to be polished is located in a workpiece carrier, also called a lens holder, which in turn is connected to a workpiece spindle and also rotates. The drive required for this is located in the workpiece spindle. The tool spindle and the workpiece spindle of the polishing machine can usually be moved in several axes. In addition, one of the two spindles can be inclined so that the geometric axes of the tool and lens form an angle to each other and intersect at the center of the radius of the spherical lens surface to be machined. The tool and workpiece spindles rotate in the same direction.

[0008] The state of the art (DE 100 44 872 A1) includes a method for polishing optical lenses or mirrors with imaging properties using a polishing machine.

[0009] According to this state of the art, the optical lens is mounted in a lens holder, which in turn is spring-mounted and therefore has axial mobility. The polishing pressure between the polishing tool and the lens is applied by springs, which are preloaded by the feed movements of at least one of the machine spindles. The lens is suctioned onto the lens support in the lens holder by applying negative pressure to its rear side. The lens support is previously adjusted to the rear side of the lens by dressing it in the polishing machine.

[0010] According to this state of the art, a lens support made of porous material is provided to support the lens. The lens is fixed to the lens support using a vacuum.

[0011] This prior art design has the disadvantage that the lens flexes, especially when processing thin lenses, because the negative pressure creates an uneven airflow. This means that the pressure on the underside of the optical lens is not uniform.

[0012] In addition, the design requires the provision of an additional guide ring to ensure "cardanic mobility" of the optical lens.

[0013] This "gimbal-like mobility" is very important so that the lens can fit seamlessly into the polishing tool, which is designed as a mold. If the lens has a cylindrical shape at its outer edge and the lens holder is also cylindrical in the area of ​​the lens mount, this mobility is not achieved to the desired degree. This is especially true because there must not be much play between the lens and the lens mount to prevent the lens from slipping due to drag forces during polishing.

[0014] The prior art (DE 10 2020 008 132 A1) also includes a workpiece carrier for securing to a first lens surface of an optical lens according to the preamble of claim 1. According to this prior art, the lens is mounted in a floating manner. A workpiece carrier is secured to a first lens side (underside of the lens) and projects into a chamber containing a pressurized polishing suspension. According to this prior art, a purely hydrostatic bearing is described. This prior art bearing with liquid has the disadvantage that the pressure application generated by a volume flow exerts different forces on the back of the lens due to the flow profile, since the flow velocity is uneven in the various regions of the optical lens.

[0015] Furthermore, the prior art (JP H04 201039 A) includes a lens holder. The lens is held by vacuum suction of air to an elastic porous body arranged in a cylinder. The lens can be easily removed from the holder because it is held by the suction force. This device is not suitable for processing thin lenses.

[0016] The technical problem underlying the invention is to provide a device for polishing an optical lens or an optical mirror, which enables precise mounting of the optical lens or optical mirror during the polishing process and prevents bending of the optical lens or optical mirror, particularly when machining thin lenses. Furthermore, a method for polishing an optical lens or an optical mirror is to be provided, with which the polishing process of the optical lens or optical mirror can be carried out with the highest accuracy due to optimized mounting of the optical lens or optical mirror during the polishing process.

[0017] This technical problem is solved by a device having the features according to claim 1 and by a method having the features according to claim 6.

[0018] The device according to the invention for polishing an optical lens or an optical mirror is defined in claim 1.

[0019] The device according to the invention has the advantage that it comprises a combination of an elastic and porous support and a hydrostatic bearing in which the polishing agent flows through the support under pressure.

[0020] The device according to the invention has the advantage that the force acting orthogonally on the first surface of the optical lens or the optical mirror is uniformly distributed and constant over the entire first surface of the optical lens.

[0021] Due to the design of the device according to the invention with an elastic and porous support and a hydrostatic bearing, the distance between the optical lens and the lens holder changes only very slightly or not at all during the polishing process. This is a significant advantage over the purely hydrostatic bearing, which is part of the state of the art.

[0022] By designing the device according to the invention with a hydrostatic bearing and the elastic and porous support, the distance between the optical lens and the polishing tool changes only very slightly or not at all during the polishing process. This is a further advantage over the purely hydrostatic bearing, which is part of the state of the art.

[0023] For the sake of simplicity, the following statements regarding the invention refer only to lenses. However, optical mirrors with an imaging function are also always meant.

[0024] According to the invention, defining the at least one first surface of the optical lens means that the optical lens is arranged in a specific position relative to the workpiece carrier. The lens is arranged in a specific position relative to the support. In this position, the lens can be subjected to a polishing process.

[0025] Fixation refers to a guiding bearing. The lens is not clamped in the workpiece carrier. Clamping could cause damage, such as breakage, to the lens.

[0026] The first surface of the optical lens is fixed to the support to allow for some play. The optical lens is mounted floating on the support. During the polishing process, the lens's distance from the polishing tool remains constant or only slightly variable. This allows for "gimbal-like" movement.

[0027] The porous, elastic support and the polishing agent, which is forced through the support under pressure, ensure a very uniform pressure application to the first surface of the optical lens. The inventive design of the device allows the polishing agent to generate greater pressure than with a purely floating support, thus achieving a uniform pressure distribution on the first surface of the optical lens.

[0028] In the prior art device with the purely hydrostatic bearing, such a high pressure cannot be generated, so that the pressure in this device does not act evenly on the first surface of the optical lens.

[0029] The device according to the invention has the advantage that a layer of polishing agent is formed on a first surface of the optical lens and on a second surface of the optical lens.

[0030] In addition, pressure is also generated on the second surface, i.e., the side opposite the first surface of the optical lens, by the polishing agent and the polishing tool. The static pressure on the first surface of the optical lens has the same static conditions as on the second surface of the optical lens. This makes it possible to machine even thin lenses. Lenses with a diameter-to-thickness ratio greater than 2.0 and less than 22 or less than 25 can be machined.

[0031] According to the invention, it is provided that during a polishing process a layer of polishing agent is formed between the first surface of the optical lens or the optical mirror and the support.

[0032] The optical lens floats on the layer of polishing agent formed between the support and the first surface of the optical lens by the pressurized polishing agent.

[0033] The porous and elastic design of the support causes the pressurized polishing agent to flow through the porous and elastic support. After emerging from the porous and elastic support, the polishing agent forms a layer between the support and the first surface of the optical lens, which creates a resistance in the direction of flow of the polishing agent. The first surface of the optical lens is mounted on this layer. Due to the uniform pressure distribution orthogonally across the first surface of the optical lens, the optical lens is movably mounted, allowing the lens to be inserted into the polishing tool, which is designed as a mold, without any constraints.

[0034] According to the invention, the pad is made of a liquid-permeable elastomer or an elastic foam, in particular foam rubber or sponge rubber.

[0035] The support for the optical lens must be fluid-permeable so that the polishing agent can flow through it. It is particularly advantageous if the polishing agent flows evenly from the support on the side facing the lens.

[0036] Since the pad is not only porous but also elastic, it is particularly advantageous to construct the pad from a fluid-permeable elastomer. The pad can also be made from an elastic foam, particularly foam rubber or sponge rubber.

[0037] Foam rubbers or sponge rubbers belong to the category of porous rubbers. These are rubber products made from solid natural or synthetic rubber with the addition of propellant gases. Porous rubbers differ in their pore structure. Foam rubber has largely closed pores, while sponge rubber has completely open and interconnected pores. This structure allows the polishing agent to flow through the foam rubber or sponge rubber.

[0038] The support is advantageously made of a foamed plastic so that the elastomers mentioned are permeable to the polishing agent, i.e. permeable to liquids.

[0039] According to an advantageous embodiment of the invention, the overlay has a SHORE A hardness between 15 and 25. A SHORE A hardness of 20 is particularly preferred.

[0040] According to a further advantageous embodiment of the invention, it is provided that the support is designed to match the shape of the first surface of the optical lens or the optical mirror, and that the support is arranged in or on the workpiece carrier in an exchangeable manner. This embodiment has the advantage that a uniform layer of the polishing agent can form between the support and the first surface of the optical lens. This equidistant or nearly equidistant layer, in turn, has the advantage that it applies a uniform and constant pressure orthogonally to the first surface of the optical lens over the entire area of ​​the first surface of the optical lens.

[0041] This ensures optimal storage of the optical lens by the device according to the invention.

[0042] To allow the support to be adapted to different optical lenses, the support is arranged in the workpiece carrier in an interchangeable manner. Depending on which optical lens is to be processed, the appropriate support is arranged in or on the workpiece carrier. The support is preferably attached to the workpiece carrier in a detachable and fixed manner. It can be fixed to the workpiece carrier, for example, using at least one screw. Other fastening devices, such as clamping devices or adhesive devices, are also possible.

[0043] According to the invention, it is provided that at least one line for the polishing agent is arranged in the workpiece carrier.

[0044] The workpiece carrier advantageously comprises a base body with a pin for clamping in a processing machine. It is also possible to provide the pin with a thread. The polishing agent is advantageously conveyed through the workpiece carrier from a reservoir to the porous elastic support, allowing the polishing agent to flow through the support and form a layer between the porous elastic support and the optical lens.

[0045] For this purpose, it is advantageous to run at least one line through the workpiece carrier. The line is sealed against the environment, so that the polishing agent only emerges from the line in the area of ​​the porous and elastic support.

[0046] The line is preferably designed as a hole in the parts of the workpiece carrier. However, the line can also be designed as a hose or pipe.

[0047] According to a further advantageous embodiment of the invention, it is provided that the at least one line has a tube which is arranged in the line so as to slide in the axial direction.

[0048] The workpiece carrier according to the invention advantageously has a spring-loaded clamping body. The porous and elastic support is arranged on the clamping body on the lens side. The clamping body is advantageously spring-loaded relative to the base body. The clamping body is spring-loaded so that the optical lens arranged in the workpiece carrier can move freely relative to the polishing tool. This spring-loaded mounting of the optical lens compensates for different thicknesses of the optical lenses to be machined.

[0049] According to an advantageous embodiment of the invention, a central spring is provided for the resilient mounting of the clamping body. However, it is also possible to provide at least two, preferably three or four, springs distributed decentrally around the circumference of the clamping body. A uniform distribution of the at least two, preferably three or four, springs around the circumference is particularly advantageous.

[0050] In order to be able to carry out the height compensation of the movement of the clamping body relative to the base body in the line for the polishing agent, a tube is advantageously provided in the at least one line, which tube is arranged to slide in the line.

[0051] Particularly advantageously, at least one sliding ring is provided for this purpose. Particularly preferably, at least two or three sliding rings are provided. The sliding rings also act as sealing rings.

[0052] Additional O-rings or sliding rings can also be provided for further sealing.

[0053] To protect the at least one spring in the workpiece carrier, a rubber bellows or expansion joint is advantageously provided between the clamping body and the base body. The rubber bellows or expansion joint allows movement of the clamping body relative to the base body in the axial direction of the workpiece carrier. The expansion joint advantageously also functions as a rotary coupling.

[0054] The tube in the at least one line of the polishing agent serves to compensate for height due to the spring mounting.

[0055] The primary purpose of the at least one spring is to compensate for the thickness of the optical lens. Height adjustment is possible thanks to the spring-loaded mounting. The spring-loaded mounting reduces the precision requirements for adjusting the polishing tool, which reduces the workload.

[0056] According to a further advantageous embodiment of the invention, a lens guide ring is provided for alignment, preferably for centered alignment, of the optical lens or the optical mirror on the support.

[0057] A gap is formed between the lens guide ring and the optical lens. Firstly, the optical lens must not be clamped, as otherwise it could be damaged during machining. Secondly, the polishing compound flows through the gap between the optical lens and the lens guide ring toward the second surface of the optical lens, i.e., the surface of the optical lens facing the polishing tool. The polishing compound is used here to polish the optical lens.

[0058] The lens guide ring is used to align the lens centrally, with a certain amount of play relative to the lens guide ring.

[0059] The lens guide ring is advantageously made of plastic to protect the lens.

[0060] The other parts of the workpiece carrier can advantageously be made of metal or other materials.

[0061] The lens guide ring can be cylindrical on its inner circumference. However, according to a further advantageous embodiment, it is also possible to design the inner surface spherical. This means that the inner surface has a protrusion in the longitudinal section of the lens guide ring. The spherical design of the inner surface promotes the "gimbal mobility" of the optical lens.

[0062] According to a further advantageous embodiment of the invention, it is provided that a gap for the polishing agent is arranged between the lens guide ring and the optical lens or the optical mirror.

[0063] The gap between the lens guide ring and the optical lens is ideally 1 / 10 of a millimeter. The gap can also be larger or smaller.

[0064] As already explained, the polishing agent can flow past the optical lens through the gap between the lens and the lens guide ring towards the second surface of the optical lens.

[0065] The polishing agent is used on the second surface of the optical lens to polish the second surface.

[0066] Because the polishing agent emerges from the support on the first surface of the optical lens and flows laterally past the optical lens, an additional cooling effect of the optical lens occurs, which is particularly beneficial during the polishing process.

[0067] The polishing agent flows through the porous support at a pressure, preferably between one and three bar. This pressure has proven particularly advantageous in preventing the porous support from becoming clogged by the solid particles of the polishing suspension. The polishing agent preferably contains particles with a size in the micrometer range. The particles are preferably in the form of granules.

[0068] According to a further advantageous embodiment of the invention, a rotational speed Dω 1 of the workpiece carrier and a rotational speed Dω 2 of the polishing tool are synchronized. Both directions of rotation are the same. However, the workpiece carrier and the polishing tool each have a different rotational speed.

[0069] The support has a shape that corresponds to the first surface of the optical lens. Accordingly, the support can be flat, convex, or concave.

[0070] The inventive method for polishing an optical lens or an optical mirror with a polishing agent using a device according to claim 1 is defined in claim 6.

[0071] The method according to the invention has the advantage that a layer of polishing agent is formed on a first surface of the optical lens and on a second surface of the optical lens.

[0072] The layer of polishing agent on the first surface of the optical lens serves to support the optical lens so that the lens can fit into the polishing tool designed as a mold during the polishing process.

[0073] The layer of polishing agent on the second surface of the optical lens serves as a processing layer, that is, the layer is formed between the optical lens and the polishing tool.

[0074] According to a further advantageous embodiment of the invention, it is provided that the polishing agent, after emerging from the support and forming the layer between the support and the optical lens or the optical mirror, flows through the gap between the guide ring and the optical lens or the optical mirror, and that the polishing agent is subsequently used on the second surface of the optical lens or the optical mirror to polish the second surface.

[0075] This design allows the polishing agent to perform several tasks.

[0076] On the one hand, the polishing compound serves as a layer for the optical lenses. On the other hand, the polishing compound flowing around the optical lens fulfills a cooling function. The back of the optical lens is continuously cooled, thus achieving temperature equalization through the flow of the polishing compound.

[0077] In addition, the polishing agent on the second surface of the optical lens is available for the polishing process.

[0078] It is possible that only the polishing compound flowing around the lens is used for the polishing process. Alternatively, it is also possible to add additional polishing compound, for example, via nozzles to the second surface of the optical lens for the polishing process.

[0079] According to a further advantageous embodiment of the invention, it is provided that the polishing agent cools the first surface, a lateral surface and the second surface of the optical lens or the optical mirror.

[0080] As already mentioned, the polishing agent performs a cooling function. The cooling action primarily occurs on the first surface of the optical lens, where the coolant passes through the porous, elastic support and hits the first surface of the optical lens. However, the cooling function also occurs on the side of the optical lens and on the surface of the optical lens.

[0081] According to a further particularly advantageous embodiment of the invention, it is provided that the polishing agent generates a constant pressure over the entire surface of the first surface of the optical lens or the optical mirror.

[0082] The constant pressure is generated by the polishing agent flowing through the support under pressure. The support has the shape of the first surface of the optical lens, so that a uniform, preferably equidistant layer of polishing agent is formed between the support and the first surface of the optical lens. Since the polishing agent advantageously flows through the support at a constant flow velocity and constant pressure, a constant pressure is exerted on the entire surface of the first surface of the optical lens. In conjunction with the pressure that the polishing tool generates via the further layer of polishing agent on the second surface of the optical lens, the optical lens is optimally supported so that the lens does not bend. As a result, the surface of the optical lens is machined, i.e. polished, with high precision during the polishing process, which also involves material removal, albeit to a small extent.

[0083] According to a further advantageous embodiment of the invention, the polishing agent flows through the support at a constant flow rate. This constant flow rate prevents clogging of the porous support by the solid particles in the polishing agent.

[0084] With the device according to the invention and the method according to the invention, it is possible to process lenses with a diameter / thickness ratio of at least 2.0 to 22 or up to 25. This means that with the device according to the invention and the method according to the invention, significantly thinner lenses can be processed than with the prior art.

[0085] The device and method according to the invention have the advantage that the static pressure on the first surface of the optical lens has the same static conditions as on the second surface of the optical lens being machined by the polishing tool. As already explained, this makes it possible for the first time to machine significantly thinner lenses, since they are not subjected to different pressures or are subjected to only minimally different pressures on the first surface and the second surface of the optical lens during the polishing process.

[0086] The liquid layer formed by the polishing agent advantageously has a thickness of 2 to 3 micrometers. The liquid layer, i.e., the layer of polishing agent, can also be slightly thicker or thinner.

[0087] Because the polishing compound flows through the support and exits there, then flows past the optical lens through the gap between the optical lens and the lens guide ring, both external lubrication and central lubrication are provided. External lubrication creates the layer of polishing compound between the polishing tool and the optical lens. The horizontal force on the optical lens is exerted by the lens guide ring.

[0088] Further features and advantages of the invention will become apparent from the accompanying drawings, which illustrate several exemplary embodiments of a tool carrier, without limiting the invention to these exemplary embodiments. In the drawings: Fig. 1 shows a workpiece carrier in longitudinal section; Fig. 2 shows a modified embodiment of a tool carrier in longitudinal section.

[0089] Fig. 1 shows the workpiece carrier 1. A lens 2 is arranged in the workpiece carrier 1. The lens 2 rests with a first surface 3 on a support 4. The support 4 is porous and elastic.

[0090] A second surface 5 of the optical lens 2 is machined by a polishing tool 6. For this purpose, the lens 2 is mounted on a gimbal so that it can fit into a tool surface 7 of the polishing tool 6.

[0091] For this purpose, a polishing agent 8 is passed through the porous support 4, which is supplied to the workpiece carrier 1 from a storage container (not shown). The polishing agent 8 flows through a line 9. The polishing agent 8 passes through the porous support 4 and forms a layer 10 of polishing agent on the first surface 3 of the optical lens 2. The optical lens 2 is mounted floating on this layer 10. In the horizontal direction, the lens 2 is held with play by a lens guide ring 11. A gap 12 is provided between the lens guide ring 11 and the optical lens 2. The gap 12 is in the Fig. 1 For clarity, it is shown relatively large. Gap 12, for example, is 1 / 10 of a millimeter.

[0092] The polishing agent 9 emerges from the porous and elastic support 4 and flows through the gap 12. The polishing agent 9 is used for polishing the second surface 5 of the optical lens 2. For this purpose, a further layer 13 of polishing agent is formed between the surface 5 of the optical lens 2 and the surface 7 of the polishing tool 6. Because the polishing agent 9 emerges with pressure, preferably one to two bar, through the porous and elastic support 4 in the direction of the first surface 3 of the optical lens 2, a constant pressure is exerted over the entire surface of the first surface 3 of the optical lens 2, orthogonal to the first surface 3 of the optical lens 2. The pressure is indicated by arrows in Fig. 1 These arrows are marked FN for a normal force.

[0093] The forces acting on the lens are composed of the vectors FV for the vertical force and FH for the horizontal force. The resulting force FR acting on the second surface 5 of the optical lens 2 is calculated as follows: FR = FN × µ.

[0094] The support 4 is arranged on a clamping body 14. The support 4 is detachably connected to the clamping body, in this case by means of screws 15, of which Fig. 1 only one screw 15 is shown. The screws are evenly distributed around the circumference of the workpiece carrier 1. The lens insert 14 is arranged in the workpiece carrier 1 in a removable, fixed manner. The clamping body 14 can be adapted to the respective lens 2 to be machined, i.e., the first surface 3 of the lens 2 to be machined. Fig. 1 The optical lens 2 has a flat first surface 3. However, the first surface can also be convex or concave (not shown).

[0095] The clamping body 14 is arranged on a base 18 to which the lens guide ring 11 is attached. The lens guide ring 11 can be designed such that the lens guide ring 11 receives the lens 2 before processing with the polishing tool 6 and that the lens 2 can be removed again after the processing process.

[0096] The lens insert 14 with the support 4 arranged thereon is spring-mounted in the direction of the double arrow A. This allows for height adjustment of the optical lens 2. This height adjustment eliminates the need for highly precise alignment of the polishing tool 6.

[0097] A spring 16 is provided for the spring-loaded mounting. The spring 16 is arranged centrally in the workpiece carrier 1. A base part 17 of the movable part of the workpiece carrier 1, the lens guide ring 11 arranged thereon with the base 18, and the support 4 arranged thereon are arranged so as to be movable in the direction of the double arrow A relative to a base body 19 of the workpiece carrier 1. The base body 19 has a pin 20 with which the workpiece carrier 1 is clamped in a machine tool (not shown).

[0098] Line 9 runs through pin 20. It terminates in a pipe 21 to allow height adjustment in the direction of the double arrow A. Three sealing rings 22 to 24 are provided to seal pipe 21. The sealing rings 22 to 24 are designed as O-rings. In addition, sliding rings 25 to 27 are provided. In principle, only one sliding ring with a sealing function is sufficient. If a sliding ring becomes leaky, it is advantageous to provide at least two, in this case three, sliding rings 25 to 27.

[0099] An O-ring 28 is also provided. The sliding, sealing, and O-rings 22 to 28 serve to prevent polishing agent 8 from entering the chamber 29 and impairing the spring 16. A rubber bellows 20 is provided as further protection against the penetration of polishing agent into the chamber 29. The rubber bellows 30 allows relative movement between the base part 17 and the base body 19.

[0100] A sliding bushing 31 is provided to allow the base part 17 to move in a guided manner within the base body 19. The sliding bushing serves to provide linear guidance for the base part 17 within the base body 19.

[0101] The base body 19 is set in a rotary motion. This rotary motion is denoted by Dω 1 . The base body 19 rotates around the axis A1. The polishing tool 6 is inclined by the angle α with the rotational axis A2 to the axis A1. The polishing tool 6 rotates at the rotational speed Dω 2 . The rotational directions of the polishing tool 6 and the base body 19 are the same. The rotational speeds Dω 1 and Dω ​​2 depend on the angle α and differ.

[0102] In addition to its sealing function, the rubber bellows 13 also represents a rotary coupling, so that the rotary movement of the base body 19 is continued onto the base part 17.

[0103] The workpiece carrier 1 according to the invention has the advantage that a layer 10, 13 of polishing agent is formed on the first surface 3 and on the second surface 5 of the optical lens 2. The formation of the layer 10 on the first surface 3 of the optical lens 2 causes constant forces FN to act on the first surface of the optical lens. This allows very thin lenses to be machined, since the static pressure on the first surface 3 of the optical lens 2 has the same static conditions as on the second surface 5 of the optical lens 2, which represents the contact surface for the polishing tool 6.

[0104] According to Fig. 1 An inner surface 32 of the lens guide ring 11 is cylindrical. As already explained, a gap 12 is provided between the optical lens 2 and the inner surface 32.

[0105] Fig. 2 shows a modified embodiment of the workpiece carrier 1.

[0106] Equal parts are in the Fig. 1 and 2 with the same reference numbers. In Fig. 2 will only point out the differences to Fig. 1 received.

[0107] According to Fig. 2 is the spring 16 of the Fig. 1 , which according to Fig. 1 is arranged centrally, replaced by several springs 33 and 34. Springs 33 and 34 are shown in the sectional plane. The springs are advantageously distributed over the circumference of the workpiece carrier 1, and particularly advantageously evenly distributed over the circumference. This means that in the present case, four springs are provided, each offset by 90°. It is also possible to provide three springs, each offset by 120°.

[0108] In addition, according to Fig. 2 The lens guide ring 11 is spherical with respect to its inner surface 32. The lens guide ring 12 has a spherical inner surface 35. The spherical inner surface 35 has the advantage that the optical lens 2 is mounted in a gimbal manner, i.e., the lens 2 has a gimbal-like mobility relative to the lens guide ring 11. This mobility allows the lens 2 to be inserted into the polishing tool 6, which is designed as a forming tool, without any constraint.

[0109] The gap 12 between the inner surface 35 of the lens guide 11 and the optical lens 2 is in Fig. 2 It is depicted significantly larger than it actually is. The gap is, for example, 1 / 10 of a millimeter. Reference numbers

[0110] 1Workpiece carrier 2Optical lens 3First surface of the optical lens 2 4Support 5Second surface of the optical lens 2 6Polishing tool 7Surface of the polishing tool 8Polishing agent 9Line 10Layer of polishing agent 11Lens guide ring 12Gap between lens guide ring and lens 13Layer of polishing agent 14Clamping body 15Screws 16Spring 17Base part 18Base of lens guide ring 19Base body 20Pin 21Tube 22Sealing ring 23Sealing ring 24Sealing ring 25Sliding ring 26Sliding ring 27Sliding ring 28O-ring 29Chamber 30Rubber bellows 31Sliding bushing 32Inner surface of the lens guide ring 11 33Spring 34Spring 35Convex inner surface of the lens guide ring 11 A Double arrow FN Normal force FV Vertical force FH Horizontal force FR Resulting force A1 Axis Base body A2 Axis Polishing tool α Angle Dω 1 Rotational speed Dω 2 Rotational speed

Claims

1. Device for polishing an optical lens or an optical mirror with a liquid polishing agent, with the device comprising a workpiece carrier for securing at least one first surface of the optical lens or of the optical mirror and with at least one line for the polishing agent being arranged in the workpiece carrier, characterized in that the workpiece carrier (1) has a porous and elastic support (4) for securing the at least one first surface (3) of the optical lens (2) or of the optical mirror, and the support (4) is formed as a support (4) permeable to the polishing agent (8), in that during a polishing process a layer (10) of polishing agent (8) is formed between the first surface (3) of the optical lens (2) or of the optical mirror and the support (4), and in that the support (4) consists of a fluid-permeable elastomer or an elastic foam, in particular foam rubber or sponge rubber.

2. Device according to Claim 1, characterized in that the support (4) is matched to a shape of the first surface (3) of the optical lens (2) or of the optical mirror, and in that the support (4) is arranged interchangeably in or on the workpiece carrier (1).

3. Device according to Claim 1, characterized in that the at least one line (9) comprises a tube (21), which is arranged in said line (9) so as to slide in the axial direction.

4. Device according to any of the preceding claims, characterized in that a lens guide ring (11) is provided for the alignment, preferably for the centred alignment, of the optical lens (2) or of the optical mirror on the support (4).

5. Device according to Claim 4, characterized in that a gap (12) for the polishing agent (8) is arranged between the lens guide ring (11) and the optical lens (2) or the optical mirror.

6. Method for polishing an optical lens or an optical mirror with a polishing agent using a device according to Claim 1, the polishing agent (8) flowing through a line (9) in the workpiece carrier, characterized in that during a polishing process the polishing agent (8) is passed through the support (4), in that a layer (10) of polishing agent (8) is formed between the support (4) and the first surface (3) of the optical lens (2) or of the optical mirror, and in that a layer (13) of polishing agent (8) is formed between a polishing tool (6) and a second surface (5) of the optical lens (2) or of the optical mirror.

7. Method according to Claim 6, characterized in that after emerging from the support (4) and forming the layer (10) between the support (4) and the optical lens (2) or the optical mirror, the polishing agent (8) flows through the gap (12) between a guide ring (11) and the optical lens (2) or the optical mirror, and in that the polishing agent (8) is then used on the second surface (5) of the optical lens (2) or of the optical mirror for polishing the second surface (5).

8. Method according to Claim 6 or 7, characterized in that the polishing agent (8) cools the first surface (3), a lateral surface and the second surface (5) of the optical lens (2) or of the optical mirror.

9. Method according to any of Claims 6 to 8, characterized in that the polishing agent (8) generates a constant pressure (FN) on the entire surface of the first surface (3) of the optical lens (2) or of the optical mirror.

10. Method according to any of Claims 6 to 9, characterized in that the polishing agent (8) flows through the support (4) at a constant flow velocity.

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