Method for determining position of optical waveguide core body of optical waveguide, method for machining optical waveguide, machine tool for machining optical waveguide, and control device

Abstract

The present invention provides a method for determining a position of an optical waveguide core body 1 of an optical waveguide 10 machined on a numerically controlled machine tool 100, the optical waveguide 10 comprising at least a core body 1 and a surrounding shell body 2, the core body 1 extending from a first end face 3 of the optical waveguide 10 to a second end face 4 of the optical waveguide 10. The method comprises providing an optical measurement system 200 including at least a light source device 211 and a detection device 212, the light source device 211 illuminating the optical waveguide 10, the optical measurement system 210 measuring the first end face 3 of the optical waveguide 10, the detection device 212 detecting radiation emitted from the first end face 3 by the illumination of the optical waveguide 10, and determining a position of a center point 5 of the core body 1 on the first end face 3 relative to the shell body 2 based on the detected radiation. The method is performed on the numerically controlled machine tool 100 and further comprises clamping the optical waveguide 10 on a worktable 20 of the numerically controlled machine tool 100. The optical measurement system 200 is arranged on the numerically controlled machine tool 100, and measurement of the first end face 3 is performed on the optical waveguide 10 clamped to the work table 20 by the optical measurement system 200 arranged on the numerically controlled machine tool 100.

Description

[Technical field]

[0001] The present invention relates to a method for determining the position of an optical waveguide core body of an optical waveguide machined by a numerically controlled machine tool, a method for machining an optical waveguide in a numerically controlled machine tool, a machine tool for machining an optical waveguide, and a control device for use in a machine tool. [Background technology]

[0002] The use of optical waveguides is known from the prior art and is used in many fields for purposes such as energy transmission, communication technology with data and signal transmission, lighting, etc. Such optical waveguides, often also called optical waveguide cables, optical fiber cables, etc., are designed to transmit electromagnetic radiation, in particular light, and for this purpose consist of at least one optical waveguide core body (also called optical fiber) and a surrounding shell body, in which the electromagnetic radiation or light to be transmitted is guided along the longitudinal direction of the core body.

[0003] In the field of communications technology, optical waveguides offer significantly higher transmission speeds and ranges than electrical conductors, allowing nearly lossless communication between transmitter and receiver without significant delay times.

[0004] In the process of manufacturing such an optical waveguide, the initial optical waveguide or optical waveguide blank is heated and then stretched along the longitudinal direction of the core body or optical waveguide in a deformation-stretching process. Depending on the implementation of the stretching process, a change in length of about 1 / 40000 in the longitudinal direction can be realized, for example, an optical waveguide with a length of 40 kilometers can be stretched from an optical waveguide blank with a length of 1 meter.

[0005] In preparation for such a drawing process, the preparation of the optical waveguide or the optical waveguide blank is usually carried out in a machine tool. For example, in the course of such preparation for a drawing process known from the prior art, a hole running as parallel as possible to the core body surrounded by the shell body is inserted in the shell body. In order to make the optical waveguide deformable and thus able to be drawn in the longitudinal direction, a hot fluid is passed through said hole in the hot drawing process.

[0006] The preparation process must be carried out with high precision and to relatively small tolerances, which is made even more difficult by manufacturing-related deviations in the original shape of the optical waveguide or the optical waveguide blank being machined, as the core body is usually not positioned exactly in the center of the shell body.

[0007] In order to compensate for such deviations, methods are known from the prior art in which the optical waveguide to be machined or the optical waveguide blank is measured by means of an optical microscope to determine the position of the core body in the optical waveguide, the measured optical waveguide or the optical waveguide blank to be machined is then clamped in a machine tool and machined taking into account the measurement results. Summary of the Invention

[0008] One object of the present invention is to provide an improved, in particular more accurate, method of machining optical waveguides on a machine tool compared to the prior art.

[0009] In order to solve this problem, the present invention provides a method for determining the position of an optical waveguide core body of an optical waveguide as claimed in claim 1, a method for machining an optical waveguide as claimed in claim 14, a machine tool for machining an optical waveguide as claimed in claim 20, and a control device as claimed in claim 29.

[0010] Each dependent claim refers to preferred embodiments which may be provided individually or in any combination.

[0011] According to a first aspect, there is provided a method for determining the position of an optical waveguide core body of an optical waveguide for machining on a numerically controlled machine tool, the optical waveguide comprising at least a core body and a shell body surrounding the core body, both extending from a first end face of the optical waveguide to a second end face of the optical waveguide. The method comprises providing an optical measurement system including at least a light source device and a detector device, and measuring the first end face of the optical waveguide by the optical measurement system, the measuring comprising illuminating the optical waveguide by the light source device, detecting radiation emitted from the first end face by illuminating the optical waveguide by the detector device, and determining a position of a center point of the core body at the first end face relative to the shell body based on the detected radiation. The method is performed on the numerically controlled machine tool and further comprises clamping the optical waveguide to a work table of the numerically controlled machine tool. The optical measurement system is arranged on the numerically controlled machine tool, and the first end face of the optical waveguide attached to the work table is measured by the optical measurement system arranged on the numerically controlled machine tool.

[0012] The method breaks away from the separate procedures known from the prior art and allows the optical waveguide to be measured for the purpose of determining the position of the optical waveguide core body while it is clamped in a machine tool for subsequent machining, which is also to be understood as optical waveguide blank, since the optical waveguide blank itself is an optical waveguide.

[0013] Compared to the prior art, the deviation between a) the actual shape of the optical waveguide in the clamped state, in particular the relative position of the core body to the shell body, and b) the measurement results can be significantly reduced or compensated for by the provided method.

[0014] In procedures known from the prior art, such deviations can occur in particular by inserting an optical waveguide measured outside the machine tool into the working space of the machine tool and clamping it there. This can be caused, for example, by different conditions between the measuring environment outside the machine tool and the measuring environment in the working space, for example temperature differences can lead to thermal deformations of the optical waveguide, which can result in deviations from the measuring result and a corresponding decrease in the subsequent machining accuracy. Mechanical deformations (including elastic deformations) caused by the application of clamping forces in the machine tool can also occur.

[0015] By measuring the optical waveguide already clamped for subsequent machining in the machine tool according to the invention, not only does the measurement environment simultaneously correspond to the machining environment, but the measurement and the machining based on the measurement results obtained therefrom are carried out under essentially the same boundary conditions for the optical waveguide, so that the aforementioned deviations occurring in the prior art are completely eliminated, and particularly precise machining can be carried out based on almost perfect measurement results.

[0016] In this sense, the accuracy of the subsequent machining by the machine tool is already improved by knowing the relative position of the center of the core body on the first end face of the clamped optical waveguide with respect to the shell body. For example, it can be ensured that when machining the shell body at the first end face, the tool is applied to the shell body and not the core body. Furthermore, said application position of the tool can be positioned particularly accurately with respect to the core body, for example to maintain a predetermined distance.

[0017] In order to ensure that all radiation can be detected or emitted, it may be necessary to align the optical measurement system with respect to the clamped optical waveguide or its first end face before measuring the first end face, for example by moving the work table or the measurement system itself.

[0018] The illumination of the optical waveguide carried out in the course of measuring the first end face is preferably carried out with electromagnetic radiation from an optical frequency range provided by a light source device, which includes ultraviolet, visible and infrared radiation, but should not be limited thereto, as long as the detection device is suitable for detecting at least a part of the frequency range of the electromagnetic radiation provided by the light source device. The detection device is preferably a camera, particularly preferably a microscope camera, which derives image data from the detected radiation for the subsequent step of determining the center point. Compared to a normal camera, a microscope camera can achieve a higher image resolution and therefore a higher measurement accuracy.

[0019] Radiation emitted by the first end face is to be understood as any electromagnetic radiation that occurs by illuminating the optical waveguide, which electromagnetic radiation is incident on the detection device, for example via an emission process, a transmission process or a reflection process from the first end face.

[0020] Due to the generally different light conducting properties of the shell body and the core body, the difference between the radiation emitted by the core body and the radiation emitted by the shell body, e.g. the difference in intensity or frequency (compared to detection in pure ambient light), can be increased by targeted illumination of the optical waveguide when detecting the radiation emitted by the first end face by the detection device. The image data thus obtained shows a higher contrast between the bodies, thus improving the accuracy of determining the center position of the core body. The simplified expression of an increased contrast of the detected radiation is intended to explain the aforementioned situation of a larger difference between the radiation components of the cladding and the core body, on the basis of which image data with an increased contrast between the bodies on the end face can be derived.

[0021] It is particularly preferred that when illuminating the light guide, the majority of the radiation is directed to the core body, such that the proportion of radiation transmitted to the core body is greater than the proportion of radiation of the light source device transmitted to the shell body. The very good conductive properties of the core body, necessary for use as a light guide, further increase the contrast of the detected radiation.

[0022] The term position is generally understood to mean a combination of information suitable for spatial description, by which the position and optionally the orientation of the object being described with respect to the selected reference system can be unambiguously determined with respect to the selected reference system. A reference system defines a reference for determining the position, and in the field of machine kinematics usually corresponds to a physical object, in particular a machine part. For example, the machine frame of a machine tool, the worktable of a machine tool, or the optical waveguide itself can be defined as a reference system. For mathematical description, a reference system is usually assigned a coordinate system fixed to the body or the reference system. The position of an object or body should be understood only as the position of an object fixed point with respect to the selected reference system. This can be determined, for example, by the position vector of the object fixed point in the (fixed to) coordinate system of the reference system. On the other hand, the orientation refers to the orientation or tilt of the object with respect to the selected reference system. This can be determined, for example, by the rotation angle of the object fixed coordinate system with respect to the coordinate system of the reference system.

[0023] The respective reference system, between which the relative positions are specified, will usually be specified below with the preposition "with respect to". Any number of coordinate systems can be assigned to each reference system. It should be noted that the choice of origin and basis vectors of the coordinate systems belonging to a reference system is in no way prescribed and can be chosen arbitrarily. Furthermore, the coordinate systems of different but coincident reference systems can also be transformed into one another, for example by shifting and / or rotating them.

[0024] The determined relative position of the center of the core body with respect to the shell body is preferably represented in a coordinate system fixed to the optical waveguide and therefore also to the shell body, which preferably has its origin on the first or second end face and preferably has two of its basis vectors in the plane of the first or second end face. In this way, the position of the center of the core body on the first end face with respect to the shell body (as a reference system) can be determined particularly simply by determining a position vector in said coordinate system.

[0025] The position of the point itself, such as the center point on the first end face in this case, does not require information about direction, but for example, the center line of the core body can be described by a position vector that describes the position to the center point on the first end face, and a direction vector that describes the direction of the center line.

[0026] Determining the location of the center point is essential for subsequent machining since the center point corresponds to the penetration point of the centerline of the core body at the first end face and, due to the manufacturing or forming process, does not usually correspond to the geometric center point of the first end face and varies from optical waveguide to optical waveguide.

[0027] Preferably, the method can be supplemented by a step performed before measuring and determining the position of the optical waveguide core body on the basis of the same outside the machine tool. The position determined in this prior art step can be supplemented by a position determined on the clamped optical waveguide, in this case at least the center point of the core body on the first end face. For this purpose, the method preferably comprises determining one or more compensation parameters, which can be used by the control device of the machine tool and which relate to the deviation in the position of the optical waveguide core body caused by clamping, on the basis of the measurement results from the upstream process and at least the position of the center point of the core body on the first end face determined relative to the shell body when the optical waveguide is clamped.

[0028] The aforementioned steps are not limited to the position on the first end face determined relative to the shell body, but can also be performed optionally based on the position determined in the following preferred embodiment of the method (such as the center point on the second end face, the center line of the core body, etc.) The compensation parameters thus determined serve to compensate for the deviation, thereby improving the accuracy of the subsequent machining of the optical waveguide.

[0029] In a preferred embodiment, illuminating the clamped optical waveguide to measure the first end-face of the clamped optical waveguide comprises illuminating at least a subsection of the second end-face of the clamped optical waveguide with a light source arrangement.

[0030] The illumination radiation emitted by the first end face essentially comprises a portion of the illumination radiation transmitted through the optical waveguide, in particular the core body, from the second end face by the light source device.

[0031] Preferably, the end face of the core body on the second end face is located completely within the irradiated subsection, and particularly preferably, the area ratio of the end face of the core body on the subsection on the second end face is greater than the area ratio of the end face of the shell body on the second end face to the subsection, so that a larger proportion of the irradiated radiation is transmitted through the core body, which further increases the contrast of the detected radiation and improves the position determination.

[0032] In a preferred embodiment, illuminating the clamped optical waveguide to measure the first end-face of the clamped optical waveguide comprises illuminating at least a subsection of the first end-face of the clamped optical waveguide with a light source arrangement.

[0033] In this case, the radiation emitted by the first end face essentially consists of a portion of the illumination radiation transmitted through the optical waveguide, in particular the core body, by the light source device, that is reflected by the first end face and a portion that is reflected at the second end face.

[0034] Due to the fact that illumination and detection are performed on the same end face, here the first end face, it is possible to provide a particularly compact optical measurement system in an advantageous manner compared to the above-mentioned embodiments, whereby the light source device and the detection device are arranged locally in close proximity to one another, preferably in a common housing, which considerably simplifies handling of the optical measurement system, for example on a machine tool (e.g. picking it up from the tool table or moving the measurement system).

[0035] Thus, the devices can be positioned together opposite the optical waveguide or the first end face in one step, whereas in the case of locally separate designs, positioning of the detection device and the light source device takes time.

[0036] In order to further increase the difference in the detected radiation of the shell body and the core body, and thus the contrast, it is particularly useful to arrange a reflecting device, for example in the form of a mirror, at the second end face in order to guide a greater proportion of the radiation transmitted by the optical waveguide from the first end face back to the first end face.

[0037] In a preferred embodiment, the optical measurement system further comprises a reflecting device for reflecting the illumination radiation provided by the light source device, and measuring the first end face of the clamped optical waveguide further comprises disposing the reflecting device opposite and facing the second end face of the clamped optical waveguide such that the reflecting device reflects at least a portion of the radiation guided through the optical waveguide starting from the illuminated first end face and thereafter emanating from the second end face to the second end face.

[0038] Preferably, the end face of the core body on the first end face is located completely within the irradiated subsection, and particularly preferably the area proportion of the end face of the core body on the subsection on the first end face is greater than the area proportion of the end face of the shell body on the first end face to the subsection, which further increases the contrast of the detected radiation and improves position detection.

[0039] In a preferred embodiment, the detector and light source devices of the optical measurement system are designed as a uniform measurement device so that they always have a constant relative positional relationship with respect to each other, which simplifies the positioning of the optical measurement system with respect to the clamped optical waveguide, since it is only necessary to position the measurement device and not the two separately designed devices.

[0040] In a preferred embodiment, at least parts of the optical measurement system, in particular the detection device and the machine table, are movable relative to one another by at least one numerically controllable axis of the machine tool.

[0041] In this way, the possibility of relative alignment of the clamped optical waveguide and the optical measuring system is implemented via controllable axes of the machine tool, in particular in the run-up to measuring the first end face, which allows conceptually different measuring configurations to be implemented in the machine tool with various advantages. For example, optical waveguides of different shapes can be measured without manually adjusting the alignment to the new shape each time, which can be done by the numerically controlled machine tool itself. In another example, the worktable with the optical waveguide attached can be moved to an area of ​​the working space intended for the measurement, separate from the machining area, and the optical measuring system is rigidly installed on the machine frame of the machine tool, so that the measuring system is as far away as possible from the machining area and as protected as possible from any possible contamination. In another example, the measuring system can be moved in and out of the working space of the machine tool via at least one numerically controllable axis, which allows the measuring system to be completely protected from contamination during machining in the working space.

[0042] A lateral movement by a numerically controllable axis is understood here to mean both a translational movement via a linear axis along the translational axis / axis of the machine tool and a rotational movement via a rotational axis about the rotational axis / axis of rotation.

[0043] In a particularly preferred embodiment, the machine tool comprises a machining device with a working spindle configured to hold a tool, and at least the detection device of the optical measuring system is arranged on the machining device. Furthermore, the machine tool is configured to move the worktable and the machining device relative to one another via a number of numerically controllable axes, in particular three linear axes and two rotary axes. It is particularly preferred that the standardized measuring device with the light source device and the detection device is arranged on the machining device.

[0044] This allows for a particularly flexible positioning of the optical measuring system with respect to the optical waveguide mounted on the machine table. At the same time, machine tools with a large number of numerically controllable axes, in particular designed as 5-axis machines, offer the possibility of carrying out a wide variety of machining operations in a wide variety of directions on the clamped optical waveguide after the position has been determined. In particular, 5-axis machine designs, in which the machining device is movable in three linear axes relative to the machine frame and the machine table is movable in two rotary axes relative to the machine frame, allow machining to obtain almost any final shape, whereby not only can the optical waveguide clamped therein be measured on one machine tool, but also all necessary machining steps can be carried out subsequently, thus saving time as well as avoiding machining errors and inaccuracies that arise from re-clamping between several machine tools and / or external measuring devices.

[0045] Furthermore, since the detection device for measurement and the tool for subsequent machining are arranged on the same machine part, the position determination results used during machining with the tool are not corrupted by position tolerances between different machine parts, making it possible to achieve particularly precise position determination for machining.

[0046] In this embodiment, it is particularly preferred that the detection device and the light source device are designed as a uniform measurement device in order to provide a compact and therefore easily mobile optical measurement system.

[0047] In a particularly preferred embodiment, at least the detection device, preferably the standardized measuring device, of the optical measuring system is accommodated in the working spindle of the machining device.

[0048] This advantageously allows the optical measuring system to be inserted and removed by the working spindle, which serves as a universal interface for the measuring system and the tool for subsequent machining. For example, the entire detection or measuring device can be removed from the tool magazine or tool holder before a process and then returned to the tool magazine. Furthermore, the tool and the detection device are essentially located in the same position relative to the machining device, which further improves the accuracy of the position determination for subsequent machining.

[0049] In a particularly preferred embodiment, the method further comprises determining a position of the first end face of the clamped optical waveguide relative to the machine tool in a first coordinate system of the machine tool, in particular relative to the machine frame of the machine tool in a worktable fixed coordinate system or relative to the worktable in a worktable fixed coordinate system, and determining a position of the center of the core body on the first end face of the clamped optical waveguide relative to the machine tool in the first coordinate system of the machine tool, in particular relative to the machine frame of the machine tool in the worktable fixed coordinate system or relative to the worktable in the worktable fixed coordinate system, based on the determined position of the first end face of the clamped optical waveguide and the determined relative position of the center of the core body on the first end face with respect to the shell body.

[0050] This provides in a particularly simple manner a description of the position of the optical waveguide or the position of the first end face of the optical waveguide suitable for use by a control device of a machine tool, which, together with the predetermined position of the centre point of the first end face relative to the shell body, leads to a description of the position of said centre point which can be used by the control device.

[0051] The reference system of the machine tool is understood to be all possible reference systems of the machine tool, whereby the individual machine parts can be understood as reference systems. The choice of the reference system for describing the determined positions is arbitrary, as is the choice of the coordinate system of the selected reference system, and the coordinate system selected for the description is called the first coordinate system. As is known from the prior art, the kinematics of the machine tool can be described using several coordinate systems, each assigned to a different reference system (i.e. machine parts), which can be converted into one another on the basis of the position parameters of the numerically controllable axes. Depending on the reference system of the machine tool, the control device performs the control of the machine tool, the determined positions with respect to the optical waveguide are converted into the coordinate system of the reference system used for control, for utilization by the control device. The advantage of describing the machine table as a reference system in a worktable fixed coordinate system is that the position of the optical waveguide determined with respect to the machine table is a constant position (the optical waveguide is fixed to the worktable) and can be converted relatively easily into other reference systems of the machine tool.

[0052] In a preferred embodiment, the position of the first end face of the clamped optical waveguide relative to the machine tool is determined using a tactile measurement system comprising a touch probe device arranged on the machine tool.

[0053] Preferably, determining the position of the first end face of the clamped optical waveguide relative to the machine tool by the tactile measurement system comprises detecting one or more positions of surface points of the clamped optical waveguide relative to the machine tool by a touch probe device of the tactile measurement system, and determining the position of the first end face of the clamped optical waveguide relative to the machine tool based on the detected one or more positions.

[0054] Preferably, determining the position of the first end face of the clamped optical waveguide relative to the machine tool by means of the tactile measurement system further comprises providing at least one shape parameter relating to the shape of the clamped optical waveguide, in particular in the form of CAD data, and determining the position of the first end face of the clamped optical waveguide relative to the machine tool is additionally performed on the basis of the provided at least one shape parameter.

[0055] By using a tactile measuring system with a touch probe device, the position of the optical waveguide relative to the machine tool can be determined as simply as possible and in a technically proven manner.

[0056] In a particularly preferred embodiment, the method further comprises determining a position of a centerline of the core body relative to the machine tool based on a position of the center of the core body on the first end face of the clamped optical waveguide determined relative to the machine tool and a position of the first end face of the clamped optical waveguide determined relative to the machine tool, the position being determined in the first coordinate system of the machine tool or in any other coordinate system, if necessary after prior transformation.

[0057] In this way, a first approach to determining the location of the centerline of the core body is provided using the simplifying assumption of a centerline perpendicular to the first end face. If the location of the first end face and the center of the core body thereon are known, the simplifying assumption allows the location of the centerline relative to the machine tool, e.g., in the first coordinate system, to be quickly identified.

[0058] In a particularly preferred embodiment, the method further comprises measuring the second end face of the clamped optical waveguide by means of an optical measuring system arranged on a numerically controlled machine tool, determining the position of the second end face of the mounted optical waveguide relative to the machine tool, and determining the position of the center point of the core body on the second end face of the mounted optical waveguide relative to the machine tool, the aforementioned steps being capable of being carried out analogously to any advantageous or preferred embodiment already described in the context of determining the position of the center point on the first end face.

[0059] In this way, the center position of the core body on the second end surface can also be provided in a form usable by the control device.

[0060] In a preferred embodiment, the method further comprises determining a position of a centerline of the core body relative to the machine tool based on a position of the center of the core body at said first and second end faces of the clamped optical waveguide determined relative to the machine tool, the position being specified in the first coordinate system of the machine tool or in any other coordinate system, if necessary after prior transformation.

[0061] In this way, based on a description of the position of the center of the core body on the first and second end faces which can be used by the control device, a particularly precise description of the position of the centerline of the core body relative to the machine tool is made possible in an advantageous manner, which, in contrast to the simplified assumption of the core body being orthogonal to the end faces, also makes it possible to detect angular deviations (see also FIG. 1b) associated with the manufacture of the core body within the shell body with high precision, which can be taken into account accordingly during subsequent machining.

[0062] According to a second aspect of the invention, there is provided a method for machining an optical waveguide with a numerically controlled machine tool, the optical waveguide having a structure already described in the course of the description of the first aspect of the invention, the method comprising providing a numerically controlled machine tool with a machine table and a machining device with a work spindle configured to accommodate a tool, the machine tool moving the machine table and the machining device relative to each other via a plurality of numerically controllable axes, in particular three linear axes and two rotary axes, the method comprising clamping the optical waveguide to the machine table of the machine tool, determining a position of an optical waveguide core body of the optical waveguide clamped to the machine table according to the method according to the first aspect of the invention, providing the determined position to a control device configured for controlling the machine tool, and machining the clamped optical waveguide by a tool accommodated by the work spindle in response to at least the determined position provided to the control device.

[0063] The method according to the second aspect relates to machining of a light wave body measured by the advantageous method according to the first aspect and allows particularly precise machining of the clamped light guide based on the precise determination of the position of the light wave guiding core body as described above.

[0064] The provided numerical machine tool is preferably a five-axis machine, in which the worktable is movable relative to the machine frame via two rotary axes and the machining device is movable relative to the machine frame via three linear axes, which allows a particularly flexible and almost unlimited positioning of the clamped optical waveguide and the working spindle, thus allowing almost unlimited machining.

[0065] In a preferred embodiment, a detection device and optionally a light source device of the optical measuring system, which may be designed in particular as a standardized measuring device, for determining the position of the optical waveguide core body, are accommodated by the work spindle of the machine tool, and a tool is accommodated by the work spindle of the machine tool for machining the clamped optical waveguide.

[0066] As a result, the work spindle advantageously acts as an interface to both the optical measurement system and the tool, minimizing errors in position determination for subsequent machining.

[0067] In a preferred embodiment, the machining of the clamped optical waveguide is a material removal process. Material removal can preferably be performed by a cutting tool or by a laser-based tool using laser radiation.

[0068] In preparation for the hot drawing process, material is removed, for example to form clamping features in the shell body or to form holes / channels for fluid-based heating. Knowing the position of the core body has the advantage that it is possible to avoid damaging the core body during machining. Instead, material can be removed in a defined relationship to the core body while maintaining particularly low tolerances.

[0069] In a preferred embodiment, the tool held by the work spindle for machining the optical waveguide is equipped with a vibration generator configured to excite the part of the tool intended for material removal to vibrate, in particular at frequencies in the ultrasonic range, during machining of the clamped optical waveguide.

[0070] This not only significantly reduces the forces required for machining, but also enables the shell body, which is usually made of a hard and brittle material, to be machined with a relatively high surface quality, e.g. with a low roughness, and in compliance with low manufacturing tolerances.

[0071] Such a high surface quality is particularly advantageous for the insertion of channels for the subsequent passage of a heated fluid in a hot drawing process, since a turbulence-free, almost laminar flow can be achieved in the interface region with the channel walls.

[0072] In a preferred embodiment, the position of the optical waveguide core body of the clamped optical waveguide is determined according to a preferred embodiment of the method according to the first aspect, in which the position of the centre line of the clamped optical waveguide is determined relative to a machine tool in order to provide said position of the centre line of the core body of the clamped optical waveguide to a control device. Machining the clamped optical waveguide comprises inserting at least one channel, preferably inserting at least two channels, into the shell body of the clamped optical waveguide, the inserted channel or channels extending continuously from the first end face substantially parallel to the centre line of the core body and at least partially through the shell body, in particular to the second end face.

[0073] By inserting a channel or channels in parallel, the optical waveguide is optimally prepared for the thermal drawing process, so that the heat transfer between the fluid flowing through the channel and the core body running parallel to it remains constant and does not vary with distance changes. In this way, a particularly uniform thermal drawing process can be performed with a uniform deformation of the core body. The insertion can be performed continuously from one end face, or partially from a first end face and then from a second end face, so that the two partial channels are joined.

[0074] Essentially parallel means that, although the position of the centerline is accurately determined, deviations during manufacturing cannot be completely avoided, and therefore essentially parallel is understood to mean parallelism within the limits of accuracy that the machine tool can maintain.

[0075] In a preferred embodiment, inserting at least one flow passage into the shell body comprises aligning the work table and the machining device such that the centerline of the core body is substantially parallel to an extension of a spindle axis of a working spindle carrying a tool by controlling one or more of a plurality of numerically controllable axes in response to a position of the centerline of the core body provided to the control device, and moving the work spindle carrying the tool and the work table relative to each other in a feed direction along the spindle axis.

[0076] In this way, the centre line of the core body is aligned exactly parallel to the feed direction of the spindle axis, so that when inserting the channels only the numerically controllable axis set up for the feed movement along the spindle axis has to be controlled, so that the actual machining operations are kept particularly simple in terms of control technology.

[0077] According to a third aspect of the present invention, a machine tool for machining an optical waveguide is provided, the optical waveguide having at least an optical waveguide core body and a shell body surrounding the core body and extending from a first end face of the optical waveguide to a second end face of the optical waveguide. The machine tool is designed as a numerically controlled machine tool and comprises at least one work table, a machining device having a working spindle configured to accommodate a tool, a control device arranged to control the machine tool, and a number of axes that can be numerically controlled via the control device for a relative movement between the work table and the machining device. An optical measuring system can be arranged on the machine tool, comprising a light source device and a detection device, and can be coupled to the control device. The control device is configured to measure a first end face of the optical waveguide attached to the work table with the optical measurement system with the optical measurement system arranged on the machine tool, the control device is configured to control the light source device to illuminate the clamped optical waveguide to detect at least the attached optical waveguide, the detection device is configured to detect radiation emitted from the illuminated first end face of the clamped optical waveguide and to transmit this descriptive detection data to an evaluation unit of the control device, and the evaluation unit is configured to determine a position of a center point of the core body on the first end face of the clamped optical waveguide with respect to the shell body based on the transmitted detection data.

[0078] The machine tool is therefore adapted to carry out the methods according to the first and second aspects of the invention with all the advantages in this respect and in the preferred embodiments already described.

[0079] Preferably, the optical measurement system is designed as part of the machine tool.

[0080] In a preferred embodiment, the evaluation unit of the control device is configured to determine the position of the first end face of the clamped optical waveguide relative to the machine tool, in particular its position relative to a work table, in particular by means of a tactile measuring system, and is further configured to determine the position of the center of the core body of the first end face of the clamped optical waveguide relative to the machine tool, in particular its position relative to the work table, based on the position of the first end face determined relative to the machine tool, and to determine the position of the center of the core body of the first end face of the clamped optical waveguide relative to the machine tool, in particular its position relative to the work table, based on a) the position of the first end face of the clamped optical waveguide determined relative to the machine tool and b) the relative position of the center of the core body on the first end face determined relative to the shell body.

[0081] In a preferred embodiment, the optical measurement system is designed such that the light source device illuminates the second end face of the clamped optical waveguide when measuring the first end face.

[0082] In a preferred embodiment, the optical measurement system is designed such that the light source device illuminates the first end face of the clamped optical waveguide when measuring the first end face.

[0083] In a preferred embodiment, the optical measurement system further includes a reflecting device that is arranged to face the second end face of the clamped optical waveguide when measuring the first end face and reflects the illumination light supplied from the light source device.

[0084] In a preferred embodiment, at least the detection device, with the optical measurement system installed, is arranged on a machine part which is movable relative to the machine frame of the machine tool, in particular on a machining device which is movable relative to the machine frame.

[0085] In a preferred embodiment, at least the detection device is accommodated in the working spindle of the machining device, with the optical measurement system installed.

[0086] Preferably, the light source device and the detector device are designed as a uniform measurement device.

[0087] In a preferred embodiment, the control device is configured to control at least one of a plurality of numerically controllable axes for machining of the clamped optical waveguide depending on one or more determination results of an evaluation part of the control device.

[0088] The determination result is to be understood as any position determined in the course of measuring the first end face and / or the second end face of the clamped optical waveguide.

[0089] In a preferred embodiment, the machine tool for performing material removal machining of the clamped optical waveguide comprises a tool held by a working spindle and having a vibration generator configured to excite the part of the tool intended for material removal to vibrate during machining of the clamped optical waveguide, in particular at frequencies in the ultrasonic range.

[0090] According to a fourth aspect, there is provided a controller for use in a machine tool according to the third aspect of the invention.

[0091] In this way, existing machine tools can be relatively easily extended with the functionality of the machine tool according to the third aspect of the invention, in particular with the possibility of determining the position of the optical waveguide core body, provided by the evaluation unit. [Brief description of the drawings]

[0092] Further preferred embodiments and their advantages, as well as more specific embodiments of the aforementioned aspects and features, are described below with the aid of the figures shown in the accompanying drawings. [Figure 1a] FIG. 2 is a perspective view showing a schematic example of an optical waveguide before machining. [Figure 1b] FIG. 2 is a perspective view showing a schematic example of an optical waveguide before machining. [Figure 2a] 1 shows a schematic structure for implementing the method according to the first and second example embodiments of the first aspect of the present invention; [Figure 2b]1 shows a schematic structure for implementing the method according to the first and second example embodiments of the first aspect of the present invention; [Diagram 3] 2a and 2b with the worktable, the clamping device and the optical waveguide; [Figure 4] 1 shows a perspective view of a part of a machine tool according to an example embodiment of a third aspect of the present invention; [Figure 5a] 2 shows a flow chart of an exemplary sequence of a method according to an example embodiment of the first aspect of the present invention; [Figure 5b] 5 shows a flowchart of an exemplary sequence of a method according to an embodiment of the second aspect of the invention, based on the flowchart of FIG. 5a.

[0093] It is emphasized that the invention is in no way limited to the embodiments described below and their features, the invention further includes modifications of said embodiments, in particular those resulting from modifications and / or combinations of individual or several features of the described embodiments, within the scope of protection of the independent claims. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0094] 1a and 1b are perspective views showing a schematic example of an optical waveguide before machining.

[0095] 1a shows a cylindrically shaped optical waveguide 10 comprising an optical waveguide core body 1 and a surrounding shell body 2. The core body 1 and shell body 2 extend from a first end face 3 to a second end face 4 of the optical waveguide 10, relative to the longitudinal axis of the optical waveguide 10. As a frame of reference, an exemplary optical waveguide or shell body fixed coordinate system 11 is shown to describe the position of the core body 1 relative to the shell body 2, with its origin at the centre of the first end face 3, whereby the basis vector x L (→ above x) and y L (→ above y) is in the plane of the first end face 3 and has a basis vector z L (→ above z) runs along the center line 9 of the optical waveguide 10 .

[0096] The optical waveguides that are measured and subsequently machined will typically have a substantially cylindrical shape as shown, with the core body 1 extending inside the shell body 2 also being substantially cylindrical, however, the present invention is not intended to be limited for use solely with optical waveguides of such shapes.

[0097] Due to manufacturing reasons, the core body 1 will generally not pass through the exact center of the shell body 2 along a centerline 7 connecting a center point 5 on the first end face 3 and a center point 6 on the second end face 4. Thus, in the example shown in Figure 1a, the core body 1 runs parallel to, but spaced from, the centerline 9 of the optical waveguide 10.

[0098] The centre point is to be understood as the surface centre point of the cross section of each of the first and second end faces 3, 4, the cross section of the optical waveguide corresponding exactly to the first or second end face 3, 4 itself.

[0099] To describe the position of the core body 1, we can use here a position vector r1 (→ above r) relative to the center point 5 on the first end face 3 or the center point 6 on the second end face 4, and a direction vector 8 describing the direction of the center line 7 of the core body 1.

[0100] In contrast to the more specific case of FIG. 1a, FIG. 1b shows an exemplary optical waveguide 10 in which the position of the core body 1 relative to the shell body 2 is more general, and the centerline 7 of the core body 1 is not parallel to the centerline 9 of the optical waveguide 10. Starting from a center point 5 on the first end face 3, the direction vector 8 of the centerline 7 of the core body 1 is not perpendicular to the first end face 3, but is parallel to the surface normal (here z L (running parallel to → above z) (see also Figure 3).

[0101] As can be seen from the example of Figures 1a and 1b, the position of the core body 1 relative to the shell body 2 can vary significantly during the manufacturing process, so that a determination of the corresponding position is necessary to ensure accurate machining of the optical waveguide 10. This is particularly advantageously solved by the method according to the first aspect of the invention, in the course of which the position of at least the centre point 5 on the first end face 3 is determined. Particularly advantageously, the position of the centre point 6 on the second end face 4 is also determined, as well as the direction vector 8 of the centre line 7 connecting the centre points 5 and 6, which can be derived therefrom.

[0102] Based on the above description of the optical waveguide, embodiments of the method and machine tool are described below.

[0103] FIG. 2a shows a schematic structure for implementing a method according to a first example embodiment of the first aspect of the present invention for determining the position of an optical waveguide core body 1 of a clamped optical waveguide 10 when illuminating and measuring a first end face 3 with a partially drawn machine tool according to the third aspect.

[0104] The optical waveguide 10 is clamped to a work table 20 of a machine tool, not shown in full here, via a clamping device 30, which is fixed to the upper side of the work table 20 via corresponding fixing bolts 34. The work table can be rotated about a first rotation axis R1 via a rotary shaft with a drive 22, for example relative to a machine frame or a swivel arm of a rotating swivel table (see also FIG. 4).

[0105] The mechanism for determining the position comprises an optical measurement system 200, which includes a light source 211 and a microscope camera 212, designed as a uniform measuring device 210 in the same housing, as well as a reflector 220. The optical paths of the light source 211 and the microscope camera 212 occur through the same opening in the housing of the measuring device 210, using for this purpose a semi-transparent mirror 213. It should be noted that the optical measurement system 200 is arranged on the machine tool, even if not explicitly shown here, and that the structure shown is in no way limited to a microscope camera, but rather any detection device capable of detecting at least a part of the radiation emitted by the light source can be used.

[0106] When measuring the first end face 3, the measuring device 210 faces the first end face 3, so that the illumination light from the light source 211 hits the first end face 3 via the semi-transparent mirror 213 and is partially transmitted and reflected there. The transmitted portion directed towards the second end face 4 is mostly reflected to the second end face 4 by the reflector facing the second end face 4 after leaving the optical waveguide, such that the illumination light emitted from the first end face in the direction of the measuring device 210 is essentially composed of a portion reflected at the first end face 3 and a portion reflected at the reflector 220.

[0107] The light irradiated from the first end face 3 passes through a semi-transparent mirror 213 and is imaged by a microscope camera 212 arranged behind the mirror.

[0108] The optical measurement system 200 is connected to a control device 50 of the machine tool, which comprises at least one evaluation unit 51. Preferably, the control device 50 further comprises a control unit 52 for controlling the numerically controllable axes of the machine tool and a memory unit 53 in which the control programs of the machine tool as well as the received data can be stored and retrieved.

[0109] The radiation captured by the microscope camera 212 is converted into corresponding image data by the microscope camera 212 and transmitted to the evaluation unit 51 of the control device 50, or the captured raw data (captured data) is transmitted directly.

[0110] The evaluation unit 51 is configured to determine, based on the transmitted data, the position of the centre point of the core body 1 of the clamped optical waveguide 10 on the first end face 3. For this purpose, any common prior art image and pattern recognition methods can be used which, based on the difference in the radiation components of the core body 1 and the shell body 2, recognise them as different objects in the evaluated acquired data and determine, using any mathematical, usually numerical, method, the centre of the core body 1 and its position on the first end face 3 relative to the shell body 2.

[0111] The position determined by the evaluation unit 51 is output in a form usable by the control device 50 so that subsequent machining of the clamped optical waveguide 10 can be performed depending on the determined position.

[0112] Preferably, the position of the centre point of the core body 1, determined relative to the shell body 2, is directly offset relative to the position of the light guide 10 relative to the machine tool, e.g. the worktable 20, to obtain the position of the centre point relative to the machine tool. The position of the light guide can be indicated, for example, by a position vector of the light guide point in the worktable fixed coordinate system 21 (see also FIG. 3).

[0113] After measuring the first end face 3 of the optical waveguide 10, the worktable 20 can be rotated about the first rotation axis R1 to rotate it by 180°, so that the second end face 4 can be measured as well. In this sense, the position determination is preferably performed fully automatically by the control device 50, which, after receiving an image or acquired data of the first end face 3, independently commands the realignment for measuring the second end face 4 and controls the light source 211 and the microscope camera 212 in the process (as when measuring the first end face 3).

[0114] FIG. 2b shows a schematic structure for implementing a method according to a second example embodiment of the first aspect of the present invention for determining the position of the optical waveguide core body 1 of a clamped optical waveguide 10 when illuminating the second end face 4 and measuring the first end face 3 with a partially depicted machine tool according to the third aspect.

[0115] The structure shown in FIG. 2b corresponds largely to the structure in FIG. 2a, but differs in the optical measurement system 200 and the corresponding procedure for determining the position.

[0116] In Fig. 2b, the light source 211 and the detection device are also designed as a uniform measurement device 210, but in contrast to the structure of Fig. 2a, the second end face 4 of the attached light guide 10 is illuminated. For this purpose, the measurement device 210 has an exemplary U-shaped design with a web 214 spanning the light guide 10, which allows the light guide 10 to be positioned between the microscope camera 212 and the light source 211.

[0117] In this case, the radiation emitted by the first end face 3 and detected by the detector 212 consists essentially of the component transmitted through the optical waveguide 10 and illuminated by the light source 211 at the second end face 4. The evaluation by the evaluation unit 51 based thereon is the same as in the process of FIG.

[0118] FIG. 3 shows a perspective view of a portion of the structure of FIGS. 2a and 2b with a work table 20, a clamping device 30, and an attached optical waveguide 10, with a simplified representation of the optical waveguide 10 replaced by the representation shown in FIG. 1b.

[0119] 2a and 2b, Fig. 3 shows a detailed structure of the clamping device 30, which comprises a lower part 31 and an upper part 32, between which the optical waveguide 10 is clamped. The clamping is performed by a corresponding clamping bolt (not shown here), which is inserted into the upper part 32 through an upper hole 35 and is screwed into the lower part 31 with a suitable threaded mating part in order to fix the optical waveguide 10 located between the lower part 31 and the upper part 32.

[0120] The clamping device 30 itself is fixed to the upper side of the worktable 20 via fixing bolts (see FIGS. 2 a , 2 b ) that are led through holes 33 , so that the optical waveguide device 10 is clamped to the worktable 20 .

[0121] In addition to FIGS. 2a and 2b, the worktable 20 also has a second rotary axis which in FIG. 3 can rotate about a second axis of rotation R2 which is orthogonal to the first axis of rotation R1.

[0122] In the following, the position of the centre line 7 of the core body 1 of the clamped optical waveguide 10 relative to the machine tool or the worktable 20 of the machine tool will be exemplarily described as a correspondingly selected reference system of the machine tool.

[0123] For the description of the worktable 20, an orthonormal worktable-fixed coordinate system 21 has been chosen. The origin of the coordinate system 21 is illustratively placed at the center of the worktable 20, so that the basis vector x M (→ above x) and y M (→ above y) runs parallel to the top of the worktable 20 and is the basis vector z M (→ above z) is perpendicular to it.

[0124] By measuring the first end face 3 and the second end face 4 in the sense of a preferred embodiment of the method according to the first aspect of the invention, both the center point 5 of the first end face 3 and the center point 6 of the second end face 4 can be indicated relative to the shell body 2 or the optical waveguide 10 itself. As an example, only the position vector running in the optical waveguide fixed coordinate system 11 is shown. r1 (→ above r) is shown. For the center point 6 on the second end face 4, by vector addition with an equivalent not shown here, the direction vector 8 of the center line 7 is determined, which can be described, for example, by the inclination angles α and β shown relative to the first end face 3.

[0125] The position of the optical waveguide 10 is described by a position vector r0 (→ above r) from the origin of the worktable fixed coordinate system 22 to the origin of the optical waveguide fixed coordinate system 11. r1 (→ above r) can be used to identify the center point 5 relative to the worktable 20. The position vector r0 (→ above r) can be determined, for example, with the aid of a tactile measurement system of the machine tool, which probes at least the first end face for position determination. The orientation of the center line 7 relative to the worktable can be similarly described by means of a direction vector 8.

[0126] The basis vectors of the coordinate systems 11 and 21 shown in Fig. 3 run parallel in pairs, so that a description of the orientation of the first end face 3 relative to the worktable 20, for example by an inclination angle, is unnecessary or self-evident. At this point, it should be noted that the first end face may be inclined relative to the coordinate system 21 of the worktable 20 due to clamping or manufacturing, and a corresponding inclination angle has to be determined in order to describe the position of the first end face 3 relative to the worktable 20. For this purpose, for example, several surface points of the optical waveguide or the first end face 3 can be examined with a tactile measuring system, so that the plane of the first end face 3 can be described, among other things, in the worktable-fixed coordinate system 22.

[0127] FIG. 4 shows a perspective view of a part of a machine tool 100 according to an example embodiment of the third aspect of the present invention, having a structure substantially corresponding to that of FIG. 1 a for measuring the first end face 3 of a clamped optical waveguide 10.

[0128] The machine tool 100 is designed as a five-axis machine and comprises a machine frame 60, a machining device 40 which is movable relative to this via three linear axes along the directions L1, L2 and L3 (forwards and backwards, respectively) and which carries a working spindle 41, and a work table 20 which is designed as a rotating swivel table about two rotation axes relative to the machine frame 60, on whose upper side a clamping device 30 is fastened for clamping the optical waveguide 10. The axis of rotation of the first rotary axis, not shown here, is perpendicular to the table surface to which the clamping device 3 is fastened, the axis of rotation R2 of the second rotary axis is again perpendicular to the axis of rotation of the first rotary axis.

[0129] In the illustrated configuration, a single measuring device 210 is housed in the working spindle 41, which essentially corresponds to the measuring device shown in FIG. 1a, with a microscope camera and a light source arranged inside.

[0130] The measuring device 210 and the optical waveguide 10 can be positioned relative to each other by lateral movement, and the orientation shown is adopted for the purpose of measuring a first end face 3 of an optical waveguide 10 clamped according to the method according to the first aspect of the invention, during which the optical waveguide 10, vertically aligned by a rotational movement of the worktable 20, is illuminated at its first end face 3.

[0131] A reflector 220 is positioned below the worktable 20 to reflect the transmitted illumination light back to the second end face 4 of the optical waveguide 10, thereby increasing the contrast when the radiation is detected by a microscope camera of the measuring device 210 directed towards the first end face 3.

[0132] The machine tool 100 is provided with a control device, not shown here, which is connected to a measuring device 210 accommodated in the working spindle 41 and has an evaluation section which evaluates the radiation detected by the microscope camera to determine the relative position of the center point of the core body on the first end face 3 with respect to the shell body.

[0133] FIG. 5a shows a flow chart of an exemplary sequence of a method according to an embodiment of the first aspect of the invention.

[0134] In step S1, an optical waveguide is clamped to a worktable of a numerically controlled machine tool on which an optical measurement system including at least a light source device and a detection device is disposed. The optical waveguide has at least one optical waveguide core body extending from a first end face of the optical waveguide to a second end face of the optical waveguide and a shell body surrounding the optical waveguide core body.

[0135] In steps S2 to S5, the first end face of the clamped optical waveguide is measured by an optical measurement system arranged in the machine tool.

[0136] In step S2, the clamped optical waveguide is aligned with respect to an optical measurement system.

[0137] In step S3, the clamped optical waveguide, in particular the first or second end face of the clamped optical waveguide, is illuminated by a light source device of the optical measurement system.

[0138] In step S4, a detection device of the optical measurement system detects radiation emitted by the first end face of the optical waveguide as a result of the optical waveguide being illuminated.

[0139] In step S5, the position of the center point of the core body relative to the shell body at the first end face of the suspended optical waveguide is determined based on the radiation detected in step S4.

[0140] FIG. 5b shows a flow chart of an exemplary sequence of a method according to an example embodiment of the second aspect of the present invention.

[0141] In a first step S1*, the position of an optical waveguide core body of an optical waveguide to be machined in the course of the method is determined on a numerically controlled machine tool having a work table and a machining device with a work spindle configured to accommodate a tool and configured to move the work table and the machining device relative to one another via a plurality of numerically controllable axes. The position is determined according to the method according to the first aspect of the invention, which in Fig. 5b corresponds exactly to the sequence described in Fig. 5a with similar steps S1-S5.

[0142] In step S2*, the positions determined in the course of step S1* are provided to a numerically controlled machine tool controller arranged to control the machine tool.

[0143] In step S3* (as described above) machining of the optical waveguide clamped in step S1 is finally carried out by a tool accommodated by a working spindle of the machine tool at least according to the positions determined from step S2* and provided to the control device.

[0144] Although the preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, the present invention is not limited to such examples.

[0145] It is emphasized again that the invention is in no way limited to the above-described embodiments and the features of these embodiments, the invention further includes modifications of said embodiments, in particular those resulting from modifications and / or combinations of individual or several features of the described embodiments, within the scope of protection of the independent claims. [Explanation of symbols]

[0146] 1. Core Body 2 Shell body 3 First end surface 4 Second end face 5 Center of core body at first end face 6 Center of core body at first end face 7 Centerline of Core Body 8 Centerline direction vector 9 Centerline of optical waveguide 10 Optical waveguide 11 Optical waveguide fixed coordinate system 20 workbench 21 Workbench fixed coordinate system 22 Drive device for first rotary shaft 30 Clamping device 31 Lower part of clamp device 32 Upper part of clamp device 33 Bolt fixing holes 34 Fixing bolt Hole for clamping 35 bolt 40 Machining equipment 41 Working spindle 50 Control device 51 Evaluation Department 52 Controls for controllable axes 53 Storage section 60 Machine Frame 100 Machine tools 200 Optical Measurement System 210 Measuring Equipment 211 Light source 212 Microscope Camera 213 Semi-transparent mirror 214 Bar 220 Reflector R1 First rotation axis R2 Second rotation axis L1 first translation direction L2 second translation direction L3 third translation direction

Claims

1. A method for determining the position of an optical waveguide core body (1) of an optical waveguide (10) machined on a numerically controlled machine tool (100), comprising the steps of: The optical waveguide (10) comprises at least the core body (1) and a surrounding shell body (2), both of which extend from a first end face (3) of the optical waveguide (10) to a second end face (4) of the optical waveguide (10); The method comprises: - providing an optical measurement system (200) comprising at least a light source device (211) and a detection device (212); - measuring the first end face (3) of the optical waveguide (10) using the optical measurement system (200); Equipped with Measuring the first end surface (3) comprises: - illuminating said optical waveguide (10) by said light source device (211); - detecting, by means of said detector (212), radiation emitted from said first end face (3) as a result of illuminating said optical waveguide (10); - determining the position of a center point (5) of the core body (1) at the first end face (3) relative to the shell body (2) based on the detected radiation; having - clamping said optical waveguide (10) to a worktable (20) of said numerically controlled machine tool (100); the optical measurement system (200) is arranged on the numerically controlled machine tool (100), and the measurement of the first end face (3) of the optical waveguide (10) clamped to the worktable (20) is performed by the optical measurement system (200) arranged on the numerically controlled machine tool (100). method.

2. Illuminating the optical waveguide (10) to measure the first end face (3) of the clamped optical waveguide (10) comprises: - illuminating at least a subsection of the second end face (4) of the clamped optical waveguide (10) by the light source device (211); Characterized by: The method of claim 1.

3. Illuminating the optical waveguide (10) to measure the first end face (3) of the clamped optical waveguide (10) comprises: - illuminating at least a subsection of the first end face (3) of the clamped optical waveguide (10) by the light source device (211); Characterized by: The method of claim 1.

4. The optical measurement system (200) further comprises a reflecting device (220) for reflecting the illumination light provided by the light source device (211); Measuring the first end face (3) of the clamped optical waveguide (10) comprises: - further comprising positioning the reflecting device (220) facing and facing the second end face (4) of the clamped optical waveguide (10) such that the reflecting device (220) reflects at least a portion of the radiation guided through the optical waveguide (10) starting from the illuminated first end face (3) and subsequently emerging from the second end face (4) and returning to the second end face (4), Characterized by: The method of claim 2.

5. the detection device (212) and the light source device (211) of the optical measurement system (200) are designed as a uniform measurement device (210); Characterized by: A method according to any one of the preceding claims.

6. at least a part of the optical measurement system (200), in particular the detection device (212) and the worktable (20) are movable relative to one another by at least one numerically controllable axis of the machine tool (100); Characterized by: A method according to any one of the preceding claims.

7. The machine tool (100) comprises a machining device (40) having a working spindle (41) adapted to receive a tool, and at least the detection device (212) of the optical measurement system (200) is arranged in the machining device (40), the machine tool (100) is adapted to move the worktable (20) and the machining device (40) relative to one another via a number of numerically controllable axes, in particular three linear axes and two rotary axes; Characterized by: The method according to claim 6.

8. at least the detection device (212) of the optical measurement system (200) is accommodated in the working spindle (41) of the machining device (40); Characterized by: The method of claim 7.

9. - determining the position of the first end face (3) of the clamped optical waveguide (10) relative to the machine tool (10) in a first coordinate system of the machine tool, in particular relative to the machine table (20) in a machine table fixed coordinate system (21); - determining the position of the center point (5) of the core body (1) on the first end face (3) of the clamped optical waveguide (10) relative to the machine tool (100) in the first coordinate system of the machine tool, in particular the worktable (20) in the worktable fixed coordinate system (21), based on the determined position of the first end face (3) of the clamped optical waveguide (10) and the determined relative position of the center point (5) of the core body (1) on the first end face (3) with respect to the shell body (2); and Characterized by: A method according to any one of the preceding claims.

10. determining the position of the first end face (3) of the clamped optical waveguide (10) relative to the machine tool (100) is performed by a tactile measurement system arranged on the machine tool (100) having a touch probe device; Characterized by:

10. The method of claim 9.

11. determining a position of a center line (7) of the core body (1) relative to the machine tool (100) based on a position of the center point (5) of the core body (1) on the first end face (3) of the clamped optical waveguide (10) determined relative to the machine tool (100) and a position of the first end face (3) of the clamped optical waveguide (100) determined relative to the machine tool (100), Characterized by:

11. The method according to claim 9 or 10.

12. - illuminating the clamped optical waveguide (10) by means of the light source device (211); - detecting, by means of said detector (212), radiation emitted from said second end face (4) upon illumination of said clamped optical waveguide (10); - determining the position of a center point (6) of the core body (1) on the second end face (4) relative to the shell body (2) based on the detected radiation emanating from the second end face (4); Equipped with - measuring the second end face (4) of the clamped optical waveguide (10) by means of the optical measuring system (200) arranged on the numerically controlled machine tool (100); - determining the position of the second end face (4) of the clamped optical waveguide (10) relative to the machine tool (100) in the first or further coordinate system of the machine tool (100), in particular relative to the worktable (20) in the worktable fixed coordinate system (21); - determining the position of the center point (6) of the core body (1) on the second end face (4) of the clamped optical waveguide (10) relative to the machine tool (100) in the first coordinate system or the further coordinate system of the machine tool (100), in particular the worktable (20) in the worktable fixed coordinate system (21), based on the position of the second end face (4) of the clamped optical waveguide (10) determined relative to the machine tool (100) and the determined relative position of the center point (6) of the core body (1) on the second end face (4) relative to the shell body (2); and Characterized by:

11. The method according to claim 9 or 10.

13. determining a position of a center line (7) of the core body (1) relative to the machine tool (100) based on the positions of the center points (5, 6) of the core body (1) at the first and second end faces (3, 4) of the clamped optical waveguide (10) determined relative to the machine tool (100), Characterized by: The method of claim 12.

14. A method for machining an optical waveguide (10) on a numerically controlled machine (100), comprising the steps of: The optical waveguide (10) has at least one optical waveguide core body (1) extending from a first end face (3) of the optical waveguide (10) to a second end face (4) of the optical waveguide (10) and a shell body (2) surrounding the optical waveguide core body (1); The method comprises: - providing a numerically controlled machine tool (100) with a work table (20) and a machining device (40) with a working spindle (41) arranged to accommodate a tool, said machine tool (100) being adapted to move said work table (20) and said machining device (40) relative to one another via a number of numerically controllable axes, in particular three linear axes and two rotary axes; - clamping said optical waveguide (10) to said worktable (20) of said machine tool (100); - determining the position of the optical waveguide core body (1) of the optical waveguide (10) mounted on the worktable (20) according to a method according to any one of claims 1 to 13; - providing said determined positions to a control device (50) configured to control said machine tool (100); - machining said clamped optical waveguide (10) by means of a tool housed by said work spindle (41) at least depending on said position determined and provided to said control device (50); To have Characterized by: method.

15. Determining the position of the optical waveguide core body (1) comprises: - the working spindle (41) of the machine tool (100) accommodates the detection device (212) and optionally the light source device (211) of the optical measurement system (200); Machining the clamped optical waveguide (10) comprises: - the working spindle (41) of the machine tool (100) picks up a tool; Characterized by: The method of claim 14.

16. said machining said clamped optical waveguide (10) being a material removing machining; Characterized by:

16. The method according to claim 14 or 15.

17. the tool accommodated by the work spindle (41) for machining the optical waveguide (10) comprises a vibration generator configured to vibrate a part of the tool intended for material removal during machining of the clamped optical waveguide (10), in particular at frequencies in the ultrasonic range, Characterized by:

17. The method of claim 16.

18. Providing the control device with the position of the centerline (7) of the core body (1) of the clamped optical waveguide (10) to determine the position of the optical waveguide core body (1) of the clamped optical waveguide (10) is performed according to a method according to one of claims 11 or 13, It is characterized by: Machining the clamped optical waveguide (10) comprises: - inserting at least one flow channel into the shell body (2) of the clamped optical waveguide (10), the inserted flow channel extending continuously from the first end face (3) substantially parallel to the center line (7) of the core body (1) at least partially through the shell body (2), in particular to the second end face (4), 18. The method according to claim 16 or 17.

19. Inserting the at least one flow passage into the shell body (2) comprises: - aligning the worktable (20) and the machining device (41) by driving one or more of the numerically controllable axes depending on the position of the centerline (7) of the core body (1) provided to the control device (50) so that the centerline (7) of the core body (1) is substantially parallel to an extension of a spindle axis of a working spindle (41) carrying the tool; - moving a work spindle (41) carrying said tool and said work table (20) relative to each other along said spindle axis in a feed direction; To have Characterized by:

20. The method of claim 18.

20. A machine tool (100) for machining an optical waveguide (10), comprising: The optical waveguide (10) has at least one optical waveguide core body (1) extending from a first end face (3) of the optical waveguide (10) to a second end face (4) of the optical waveguide (10) and a shell body (2) surrounding the optical waveguide core body (1); The machine tool (100) is a numerically controlled machine tool (100) and includes at least - a workbench (20), a machining device (40) having a working spindle (41) adapted to receive a tool; a control device (50) configured to control said machine tool (100); - a plurality of numerically controllable axes, controllable via said control device (50) for the relative movement of said worktable (20) and said machining device (40); Equipped with An optical measurement system (200) comprising a light source device (211) and a detection device (212) and connectable to the control device (50) can be arranged on the machine tool (100); the control device (50) having the optical measurement system (200) arranged on the machine tool (100) is configured to measure a first end surface (3) of the optical waveguide (10) mounted on the work table (20) by the optical measurement system (200); It is characterized by: The control device (50) is configured at least to control the light source device (211) to illuminate the clamped optical waveguide (10); the detection device (212) is configured to detect radiation emitted from the first end face (3) of the illuminated clamped optical waveguide (10) and to transmit explanatory detection data therefrom to an evaluation part (51) of the control device (50); the evaluation unit (51) is configured to determine a position of a center point (5) of the core body (1) on the first end face (3) of the clamped optical waveguide (10) relative to the shell body (2) based on the transmitted detection data. Machine tools (100).

21. the evaluation unit (51) of the control device (50) is configured to determine the position of the first end face (3) of the attached optical waveguide (10) relative to the machine tool (100), in particular the work table (20), in particular by means of a tactile measuring system, and is further configured to determine the position of the center point (5) of the core body (1) on the first end face (3) of the attached optical waveguide (10) relative to the machine tool (100), in particular the work table (20), based on the position of the first end face (3) of the clamped optical waveguide (10) determined relative to the machine tool (100) and the relative position of the center point (5) of the core body (1) on the first end face (3) determined relative to the shell body (2); Characterized by: The machine tool (100) of claim 20.

22. the optical measurement system (200) is designed such that the light source device (211) illuminates the second end face (4) of the clamped optical waveguide (10) when measuring the first end face (3); Characterized by:

22. Machine tool (100) according to one of claims 20 or 21.

23. the optical measurement system (200) is designed such that, when measuring the first end face (3), the light source device (211) illuminates the first end face (3) of the clamped optical waveguide (10); Characterized by:

23. The machine tool (100) of claim 22.

24. the optical measurement system (200) further comprises a reflecting device (220) for reflecting the illumination light provided by the light source device (211), which is arranged opposite to and faces the second end face (4) of the clamped optical waveguide (10) when measuring the first end face (3); Characterized by:

24. The machine tool (100) of claim 23.

25. when the optical measurement system (200) is arranged, at least the detection device (212) is arranged on a machine part (100) movable with respect to a machine frame (60) of the machine tool (100), in particular on a machining device (40) movable with respect to the machine frame (60), Characterized by: A machine tool (100) according to one of claims 20 to 24.

26. when said optical measurement system (200) is arranged, at least said detection device (212) is accommodated by said working spindle (41) of said machining device (40); Characterized by:

26. The machine tool (100) of claim 25.

27. the control device (50) is configured to control at least one, in particular all, of the plurality of numerically controllable axes depending on one or more determination results of the evaluation unit (51) of the control device (50) for machining the clamped optical waveguide (10); Characterized by: A machine tool (100) according to one of claims 20 to 26.

28. the machine tool (100) for machining the clamped optical waveguide (10) with material removal comprises a tool accommodated by the work spindle (41) and a vibration generator configured to vibrate a part of the tool provided for material removal during machining of the clamped optical waveguide (10), in particular at frequencies in the ultrasonic range, Characterized by: A machine tool (100) according to one of claims 20 to 27.

29. A control device (50) for use in a machine tool (100) according to any one of claims 20 to 28.

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