Patent Application
20240342860
Applicant claims priority under 35 U.S.C. § 119 of European Application No. 23167981.2 filed on Apr. 14, 2023, the disclosure of which is incorporated by reference.
The invention relates to a device for polishing an optical lens or an optical mirror and to a method for polishing an optical lens or an optical mirror.
In the following text, the term lenses is used for linguistic simplification. However, optical mirrors having an imaging function are always meant, as well.
In practice, optical lenses are produced from transparent materials, by means of multiple grinding processes or other chip-removing machining methods. The materials can be mineral glass or suitable plastics.
In practice, the optical lenses are produced from blanks, in multiple work processes. Polishing follows the grinding processes, during which polishing the surface is made smooth. Usually, what are called diamond cup wheels are used for grinding; rough and precision grinding is carried out using them. These tools have a diamond edging on their blade, which edging is structured to be coarser or finer in accordance with the grinding process to be carried out.
In contrast, polishing using corresponding polishing machines is carried out, in practice, using tools having a surface that consists of a rather soft material. In a possible embodiment, the surface of the polishing tool is covered with a soft PU film (polyurethane film) glued onto it in the work region, which film is referred to as a polishing film. A polishing suspension ensures the removal of material; it is supplied to the work region during the polishing process and contains micro-particles that ensure the desired removal of material. There are also polishing suspensions that can additionally remove material by means of a chemical process.
From practice, it is known to form the basic body of the polishing tool from a solid material. The basic body has a shaping in the work region that approximately corresponds to the negative imprint of the surface to be machined, of the lens to be polished. This region of the polishing tool has the aforementioned polishing film glued onto it, and this film is very precisely dressed using a dressing tool. After the dressing process, the surface of the polishing film corresponds very precisely to the negative imprint of the optical lens. Such polishing tools are referred to as shaping tools. However, polishing tools have also become known that have a surface, in the work region, that consists of a material that has the properties of a polishing film, so that an additional polishing film is not necessary.
The polishing tool is attached, as is known from practice, to a tool spindle of a polishing machine, by which it is put into rotation. The lens to be polished is situated in a workpiece carrier, also called a lens holder, which in turn is connected with a workpiece spindle and also rotates. The drive required for this is situated in the workpiece spindle. The tool spindle and the workpiece spindle of the polishing machine can usually be moved in multiple axes. Furthermore, one of the two spindles can be set at a slant, so that the geometrical axes of the tool and the lens form an angle relative to one another, and intersect at the center point of the radii of the spherical lens surface to be machined. The tool spindle and the workpiece spindle have the same direction of rotation.
A method for polishing optical lenses or mirrors having imaging properties, using a polishing machine, is part of the state of the art (DE 100 44872 A1).
According to this prior art, the optical lens is mounted in a lens holder, which in turn is mounted resiliently and therefore possesses axial mobility. The polishing pressure between the polishing tool and the lens is applied by springs, after these have been biased by means of setting movements of at least one of the machine spindles. The lens is held in place on the lens lining, in the lens holder, by suction, by means of applying a partial vacuum on its rear side. In this regard, the lens lining is previously adapted to the rear side of the lens, by means of dressing in the polishing machine.
According to this prior art, a lens lining composed of porous material is provided, which lining carries the lens. By means of a partial vacuum, the lens is fixed in place on the lens lining.
This embodiment, which belongs to the prior art, has the disadvantage that the lens bends, in particular if thin lenses are being worked, because the partial vacuum generates a non-uniform air stream. This means that the pressure on the underside of the optical lens is not uniform.
Furthermore, it is necessary, on the basis of the design, that an additional guide ring is provided, which guarantees a “cardanic mobility” of the optical lens.
This “cardanic mobility” is very important, so that the lens can be inserted into the polishing tool, which is configured as a shaping tool, without any force. If the lens has a cylindrical shape on its outer edge, and the lens holder is also configured to be cylindrical in the region of the lens receptacle, this possibility does not exist to the desired degree. This holds true all the more because no great play is allowed to be present between the lens and the lens receptacle, so that the lens does not slip through as the result of the dragging forces that occur during polishing.
Furthermore, a workpiece carrier for being fixed in place on a first lens surface of an optical lens belongs to the state of the art (DE 10 2020 008 132 A1). According to this prior art, the lens is mounted so as to float. A workpiece carrier is fixed in place on a first lens side (underside of the lens) and projects into a chamber, in which a polishing suspension to which pressure is applied is situated. According to this state of the art, a purely hydrostatic mounting is described. This mounting with liquid, which belongs to the state of the art, has the disadvantage that due to the pressure application, which is produced by means of a volume stream, different forces are applied to the rear side of the lens, as the result of the flow profile, since the flow velocity is non-uniform in the different regions of the optical lens.
The technical problem on which the invention is based consists of indicating a device for polishing an optical lens or an optical mirror, with which device precise mounting of the optical lens or of the optical mirror during the polishing process is made possible, and bending of the optical lens or of the optical mirror is prevented, in particular if thin lenses are being worked. Furthermore, a method for polishing an optical lens or an optical mirror is supposed to be indicated, with which method the polishing process of the optical lens or of the optical mirror can be carried out in the greatest possible range of precision, on the basis of optimized mounting of the optical lens or of the optical mirror during the polishing process.
This technical problem is solved by means of a device having the characteristics according to one aspect of the invention as well as by a method having the characteristics according to another aspect of the invention.
The device according to the invention, for polishing an optical lens or an optical mirror, using a liquid polishing agent, wherein the device has a workpiece carrier for fixing in place at least a first surface of the optical lens or of the optical mirror, is characterized in that the workpiece carrier has a porous and elastic lining for fixing in place the at least one first surface of the optical lens or of the optical mirror, and that the lining is configured as a lining that is permeable for the polishing agent.
The device according to the invention has the advantage that it has a combination of an elastic and porous lining and a hydrostatic mounting, in which the polishing agent flows through the lining with pressure.
The device according to the invention has the advantage that the force that acts orthogonally on the first surface of the optical lens or of the optical mirror is uniformly distributed and constant over the entire first surface of the optical lens.
By means of the configuration of the device according to the invention, with an elastic and porous lining and a hydrostatic mounting, the distance between the optical lens and the lens holder does not change or only changes very slightly during the polishing process. This is a significant advantage as compared with a purely hydrostatic mounting, which is part of the state of the art.
By means of the configuration of the device according to the invention, with a hydrostatic mounting and the elastic and porous lining, the distance between the optical lens and the polishing tool does not change or changes only very slightly during the polishing process. This is a further advantage as compared with a purely hydrostatic mounting, which is part of the state of the art.
The following statements with regard to the invention are made only for lenses, for linguistic simplification. However, optical mirrors having an imaging function are always meant in the same way.
Fixing in place the at least one first surface of the optical lens is understood to mean, according to the invention, 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 lining. In this position, the lens can be subjected to a polishing process.
Fixing in place should be understood to mean guided mounting. The lens is not clamped in place in the workpiece carrier. If it were clamped, the lens could be damaged, for example it could break.
Fixing in place the first surface of the optical lens serves to mount the lens with play. The optical lens is mounted to float on the lining. The lens does not assume any distances or only insignificantly different distances from the polishing tool during the polishing process. As a result, “cardanic mobility” is possible.
As a result of the porous, elastic lining and of the polishing agent that is passed through the lining with pressure, a very uniform application of pressure to the first surface of the optical lens occurs. By means of the configuration according to the invention, of the device, a greater pressure can be generated by the polishing agent than in the case of a purely floating mounting, so that the uniform distribution of pressure onto the first surface of the optical lens is achieved.
In the case of the device that belongs to the state of the art, with the purely hydrostatic mounting, it is not possible to produce such a great pressure, so that the pressure does not act uniformly on the first surface of the optical lens in the case of this device.
The device according to the invention has the advantage that a layer of polishing agent is formed, in each instance, on a first surface of the optical lens and on a second surface of the optical lens.
Furthermore, a pressure is also produced on the second surface, in other words the side that lies opposite the first surface of the optical lens, by means of 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. In this way, it is possible to also work on thin lenses. Lenses that have a diameter/thickness ratio of greater than 2.0 and less than 22 or less than 25 can be worked on.
According to a particularly preferred embodiment of 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 of the optical mirror and the lining.
The optical lens floats on the layer of polishing agent that is formed between the lining and the first surface of the optical lens, by means of the polishing agent to which pressure is applied.
The porous and elastic configuration of the lining brings about the result that the polishing agent, to which pressure is applied, flows through the porous and elastic lining. After exiting from the porous and elastic lining, the polishing agent forms a layer between the lining and the first surface of the optical lens, which forms a resistance in the flow direction of the polishing agent. The first surface of the optical lens is mounted on this layer. By means of the uniform distribution of pressure orthogonally on the first surface of the optical lens, the optical lens is movably mounted, so that the lens can be inserted into the polishing tool, which is configured as a shaping tool, without any force.
According to a further advantageous embodiment of the invention, it is provided that the lining consists of an elastomer that is permeable for liquid, or of an elastic foam material, in particular sponge rubber or foam rubber.
The lining for the optical lens must be permeable for liquids, so that the polishing agent can flow through the lining. It is particularly advantageous if the polishing agent exits from the lining uniformly on the side of the lining that faces the lens.
Since the lining has not only the property that it is porous but also the property that it is elastic, it is particularly advantageous to form the lining from an elastomer that is liquid-permeable. The lining can also consist of an elastic foam material, in particular a foam rubber or a sponge rubber.
Foam rubbers or sponge rubbers are part of the group of pore rubbers. These are rubber articles that are produced from solid natural rubber or synthetic rubber, with the addition of propellant gases. Pore rubbers differ in terms of their pore structure. Foam rubber has extensively closed pores, and sponge rubber has completely open pores, which stand in connection with one another. As the result of this structure, it is possible for the polishing agent to flow through the foam rubber or the sponge rubber.
It is advantageous if the lining is formed from a foamed plastic, so that the aforementioned elastomers are permeable for the polishing agent, in other words permeable for liquid.
According to an advantageous embodiment of the invention, the lining has a SHORE A hardness between 15 and 25. A SHORE A hardness of 20 is particularly preferred.
According to another advantageous embodiment of the invention, it is provided that the lining is configured to be adapted to a shape of the first surface of the optical lens or of the optical mirror, and that the lining is arranged in or on the workpiece carrier, so as to be replaceable. This embodiment has the advantage that a uniform layer of the polishing agent can form between the lining and the first surface of the optical lens. This equidistant or almost 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 surface of the first surface of the optical lens.
In this way, optimal mounting of the optical lens is guaranteed by means of the device according to the invention.
In order to make it possible to configure the lining so that it is adapted to different optical lenses, the lining is arranged in the workpiece carrier so as to be replaceable. Depending on the optical lens that is to be worked on, the matching lining is arranged in or on the workpiece carrier. It is advantageous if the lining is fixed in place on the workpiece carrier, in a releasable manner. For example, it can be fixed in place on the workpiece carrier by means of at least one screw. Other fastening means, such as clamping devices or clipping devices, are also possible.
According to a further advantageous embodiment of the invention, it is provided that at least one line for the polishing agent is arranged in the workpiece carrier.
It is advantageous if the workpiece carrier has a basic body that has a pin for being held in place in a processing machine. The possibility also exists of providing the pin with a thread. It is advantageous if the polishing agent is passed through the workpiece carrier from a supply container, up to the porous elastic lining, so that the polishing agent can flow through the lining and can form a layer between the porous elastic lining and the optical lens.
For this purpose, it is advantageous if it is provided that at least one line is passed through the workpiece carrier. The line is structured to be sealed off from the surroundings, so that the polishing agent only exits from the line in the region of the porous and elastic lining.
It is advantageous if the line is configured as a bore in the parts of the workpiece carrier. However, the line can also be configured as a hose or pipe.
According to another advantageous embodiment of the invention, it is provided that the at least one line has a pipe that is arranged in the line so as to slide in the axial direction.
It is advantageous if the workpiece carrier according to the invention has a resilient mounting of a holding body. The porous and elastic lining is arranged on the holding body, on the lens side. It is advantageous if the holding body is mounted resiliently relative to the basic body. The holding body is mounted resiliently so that the optical lens arranged in the workpiece carrier can move out of the way relative to the polishing tool. By means of this resilient mounting of the optical lens, different thicknesses of the optical lenses to be worked on are balanced out.
According to an advantageous embodiment of the invention, a central spring is provided for the resilient mounting of the holding body. However, it is also possible to provided at least two, preferably three or four springs, distributed decentralized over the circumference of the holding body. Particularly advantageously, a uniform distribution of the at least two, advantageously three or four springs over the circumference is provided.
In order to make it possible to carry out the height equalization of the movement of the holding body relative to the basic body in the line for the polishing agent, it is advantageous if a pipe is provided in the at least one line, which pipe is arranged in the line so as to slide.
Particularly advantageously, at least one slide ring is provided for this purpose. Particularly preferably, at least two or three slide rings are provided. The slide rings simultaneously act as sealing rings.
For further sealing, additional O-rings or slide rings can additionally be provided.
For protection of the at least one spring in the workpiece carrier, it is advantageous if rubber bellows or folded bellows are provided between the holding body and the basic body. The rubber bellows or folded bellows allow movements of the holding body relative to the basic body in the axial direction of the workpiece carrier. Furthermore, it is advantageous if the folded bellows additionally have the function of a rotational coupling.
The pipe in the at least one line of the polishing agent serves for height equalization on the basis of the resilient mounting.
Primarily, the at least one spring serves for equalization of the thickness of the optical lens. Height equalization is possible by means of the at least one spring. By means of the resilient mounting, the demands regarding the precision of the adjustment of the polishing tool are not as great, and this reduces the work effort.
According to another advantageous embodiment of the invention, it is provided that a lens guide ring is provided for alignment, preferably for centered alignment of the optical lens or of the optical mirror on the lining.
A gap is formed between the lens guide ring and the optical lens. For one thing, the optical lens is not allowed to be wedged in place, since it could be damaged during machining. For another thing, the polishing agent flows through the gap between the optical lens and the lens guide ring, in the direction of the second surface of the optical lens, in other words the surface of the optical lens that faces the polishing tool. Here, the polishing agent is used for polishing the optical lens.
The lens guide ring serves to align the lens so that it is centered, specifically with a certain play relative to the lens guide ring.
It is advantageous if the lens guide ring is formed from plastic, so as to provide protection for the lens.
The other parts of the workpiece carrier can be advantageously formed from metal or from other materials.
The lens guide ring can be configured cylindrically on its inside circumference. According to a further advantageous embodiment, however, it is also possible to configure the inner surface spherically. This means that in a longitudinal section of the lens guide ring, the inner surface has a protrusion on the inner surface. The spherical configuration of the inner surface promotes the “cardanic mobility” of the optical lens.
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.
It is advantageous if the gap between the lens guide ring and the optical lens amounts to 1/10 millimeter. The gap can also be larger or smaller.
As has already been explained, the polishing agent can flow past the optical lens, through the gap between the lens and the lens guide ring, in the direction of the second surface of the optical lens.
The polishing agent is used on the second surface of the optical lens, for polishing the second surface.
Because of the fact that the polishing agent exits from the lining on the first surface of the optical lens, and flows past the optical lens on the side, a cooling effect of the optical lens additionally occurs, and this has a particularly advantageous effect during the polishing process.
The polishing agent flows through the porous lining at a pressure, advantageously a pressure of one to two bar. This pressure has proven to be particularly advantageous, so that the porous lining does not become clogged with the solids particles of the polishing suspension. It is advantageous if the polishing agent contains particles having a size in the micrometer range. It is advantageous if the particles are configured as grains.
According to another advantageous embodiment of the invention, a speed of rotation Dω1 of the workpiece carrier and a speed of rotation Dω2 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 speed of rotation.
The lining has a shape that corresponds to the first surface of the optical lens. Accordingly, the lining can be configured to be planar or convex or concave.
The method according to the invention, for polishing an optical lens or an optical mirror, using a polishing agent and using a device according to claim 1, is characterized in that during a polishing process, the polishing agent is passed through the lining, that a layer composed of polishing agent is formed between the lining and the first surface of the optical lens or of the optical mirror, and that a layer of polishing agent is formed between a polishing tool and a second surface of the optical lens or of the optical mirror.
The method according to the invention has the advantage that a layer of polishing agent is formed, in each instance, on a first surface of the optical lens and on a second surface of the optical lens.
The layer composed of polishing agent that is formed on the first surface of the optical lens serves for mounting of the optical lens, so that the lens cannot insert itself into the polishing tool, which is formed as a shaping tool, during the polishing process.
The layer composed of polishing agent that is formed on the second surface of the optical lens serves as a processing layer, in other words the layer is formed between the optical lens and the polishing tool.
According to another advantageous embodiment of the invention, it is provided that the polishing agent, after exiting from the lining and forming the layer between the lining and the optical lens or of the optical mirror, flows through the gap between the guide ring and the optical lens or of the optical mirror, and that the polishing agent is subsequently used on the second surface of the optical lens or of the optical mirror, to polish the second surface.
By means of this embodiment, the polishing agent fulfills multiple functions.
For one thing, the polishing agent serves as a layer for mounting the optical lenses. For another thing, the polishing agent, which flows around the optical lens, performs a cooling function. The rear side of the optical lens is constantly cooled, and thereby a temperature equalization is achieved by means of the flow of the polishing agent.
Furthermore, the polishing agent on the second surface of the optical lens is available for the polishing process.
It is possible that only the polishing agent that flows around the lens is used for the polishing process. Alternatively, it is also possible to additionally supply polishing agent to the second surface of the optical lens, for the polishing process, for example by way of nozzles.
According to a further advantageous embodiment of the invention, it is provided that the polishing agent cools the first surface, a side surface, and the second surface of the optical lens or of the optical mirror.
As has already been explained, the polishing agent fulfills a cooling-function. The primary cooling takes place on the first surface of the optical lens, where the coolant passes through the porous, elastic lining and impacts the first surface of the optical lens. However, the cooling function also exists on the side of the optical lens, as well as on the top surface of the optical lens.
According to another particularly advantageous embodiment of the invention, it is provided that the polishing agent produces a constant pressure on the entire surface area of the first surface of the optical lens or of the optical mirror.
The constant pressure is produced in that the polishing agent flows through the lining with pressure. The lining has the shape of the first surface of the optical lens, so that a uniform, preferably equidistant layer of polishing agent forms between the lining and the first surface of the optical lens. Since the polishing agent advantageously flows through the lining at a constant flow velocity and a constant pressure, a constant pressure is exerted on the entire surface area of the first surface of the optical lens. In interaction with the pressure that the polishing tool produces over the further layer of polishing agent on the second surface of the optical lens, the optical lens is optimally mounted, so that the lens does not bend. In this way, the top surface of the optical lens is worked, in other words polished, with great precision during the polishing process, during which a removal of the material, although only to a small extent, also takes place.
According to another advantageous embodiment of the invention, it is provided that the polishing agent flows through the lining at a constant flow velocity. By means of the constant flow velocity, clogging of the porous lining with the solids particles in the polishing agent is prevented.
Using the device according to the invention and the method according to the invention, it is possible to process lenses having a diameter/thickness ratio of at least 2.0 up to 22 or up to 25. This means that using the device according to the invention and the method according to the invention, clearly thinner lenses can be processed, as compared with the state of the art.
In the case of the device according to the invention and the method according to the invention, the advantage exists that the static pressure on the first surface of the optical lens has the same static states as on the second surface of the optical lens, which is being processed by the polishing tool. As has already been explained, it is thereby possible, for the first time, to process clearly thinner lenses, since these are not exposed to different pressures or merely minimally different pressures on the first surface and the second surface of the optical lens during the polishing process.
The liquid layer formed by the polishing agent advantageously has a thickness of 2 to 3 micrometers. The liquid layer, in other words the layer composed of polishing agent, can also be slightly thicker or thinner.
Because of the fact that the polishing agent flows through the lining and exits there, and subsequently flows past the optical lens through the gap between the optical lens and the lens guide ring, external lubrication and central lubrication is provided. The external lubrication serves for producing the layer composed of polishing agent between the polishing tool and the optical lens. The horizontal force on the optical lens is exerted using the lens guide ring.
Further characteristics and advantages of the invention are evident from the related drawings, in which multiple exemplary embodiments of a tool carrier are shown, without restricting the invention to these exemplary embodiments. The drawings show:
A second surface 5 of the optical lens 2 is processed by a polishing tool 6. For this purpose, the lens 2 is mounted cardanically, so that it can insert itself into a tool surface 7 of the polishing tool 6.
For this purpose, a polishing agent 8 is passed through the porous lining 4, which agent is supplied to the workpiece carrier 1 from a supply container (not shown). The polishing agent 8 flows through a line 9. The polishing agent 8 passes through the porous lining 4 and forms a layer 10 composed of polishing agent on the first surface 3 of the optical lens 2. The optical lens 2 is mounted to float on this layer 10. In the horizontal direction, the lens 2 is held with play by means of 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 shown relatively large in
The polishing agent 9 exits from the porous and elastic lining 4 and flows through the gap 12. The polishing agent 9 is used for polishing on the second surface 5 of the optical lens 2. For this purpose, a further layer 13 composed of polishing agent is formed between the top surface 5 of the optical lens 2 and the top surface 7 of the polishing tool 6. Because of the fact that the polishing agent 9 exits at pressure, preferably one to two bar, through the porous and elastic lining 4, in the direction of the first surface 3 of the optical lens 2, a constant pressure, orthogonal to the first surface 3 of the optical lens 2, is exerted over the entire surface of the first surface 3 of the optical lens 2. The pressure is shown with arrows in
The forces that act on the lens are composed of the vectors FV for the vertical force and FH for the horizontal force. The resulting force FR that acts on the second surface 5 of the optical lens 2 is composed as follows: FR=FN×μ.
The lining 4 is arranged on a holding body 14. The lining 4 is releasably connected to the holding body, in the present case by means of screws 15, of which only one screw 15 is shown in
The holding body 14 is arranged on a base 18, to which the lens guide ring 11 is attached. The lens guide ring 11 can be configured in such a manner that the lens guide ring 11 holds the lens 2 before it is processed using the polishing tool 6, and that after the processing process, the lens 2 can be removed again, accordingly.
The holding body 14 with the lining 4 arranged on it is mounted resiliently in the direction of the double arrow A. In this way, a height equalization of the optical lens 2 is possible. Because of this height equalization, it is not necessary to precisely align the polishing tool 6 in terms of height.
A spring 16 is provided for the resilient 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 having the base 18, arranged on the ring, and the lining 4 arranged on that, are arranged to be movable relative to a basic body 19 of the workpiece carrier 1, in the direction of the double arrow A. The basic body 19 has a pin 20 with which the workpiece carrier 1 is clamped into a machine tool (not shown).
The line 9 leads through the pin 20. It opens into a pipe 21, so as to make height equalization in the direction of the double arrow A possible. Three sealing rings 22 to 24 are provided for sealing off the pipe 21. The sealing rings 22 to 24 are configured as O-rings. Furthermore, slide rings 25 to 27 are provided. Fundamentally, only one slide ring, which has a sealing function, is sufficient. If a slide ring develops a leak, it is advantageous if at least two, in the present case three slide rings 25 to 27, are provided.
Furthermore, an O-ring 28 is provided. The slide rings, sealing rings, and O-rings 22 to 28 serve to ensure that no polishing agent 8 gets into the space 29 and impairs the spring 16. As further protection against the penetration of polishing agent into the space 29, rubber bellows 30 are provided. The rubber bellows 30 allow a relative movement between the base part 17 and the basic body 19.
In order for the base part 17 to be able to move, guided in the basic body 19, a slide bushing 31 is provided. The slide bushing serves for linear guidance of the base part 17 in the basic body 19.
The basic body 19 is put into a rotational movement. This rotational movement is indicated with Dω1. The basic body 19 rotates about the axis A1. The polishing tool 6 is inclined by the angle α, with the axis of rotation A2, relative to the axis A1. The polishing tool 6 rotates with the speed of rotation Dω2. The directions of rotation of the polishing tool 6 and of the basic body 19 are the same. The speeds of rotation Dω1 and Dω2 are dependent on the angle α and are different.
The rubber bellows 30 represent not only the sealing function but also a rotational coupling, so that the rotational movement of the basic body 19 continues on the base part 17.
The workpiece carrier 1 according to the invention has the advantage that a layer 10, 13 composed of polishing agent is formed, in each instance, 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 brings about the result that constant forces FN act on the first surface of the optical lens. As a result, very thin lenses can be processed, since the static pressure on the first surface 3 of the optical lens 2 has the same static states as on the second surface 5 of the optical lens 2, which represents the contact surface to the polishing tool 6.
According to
The same parts are provided with the same reference numbers in
According to
Furthermore, according to
The gap 12 between the inner surface 35 of the lens guide 11 and the optical lens 2 is clearly shown to be greater in
| Number | Date | Country | Kind |
|---|---|---|---|
| 23167981.2 | Apr 2023 | EP | regional |
