Machining system and method for laser machining a workpiece

Abstract

The invention relates to a machining system for laser machining a workpiece (104), comprising at least one laser beam source (106) for providing a plurality of coherent laser beams (110), a phase adjustment unit (114) for adjusting a respective phase difference between the coherent laser beams (110), an amplifying unit (118) for amplifying the coherent laser beams (110), wherein respective amplified coherent laser beams (122) are formed by amplifying the respective coherent laser beams (110), a processing optic (124) for combining the amplified coherent laser beams (122) to form at least one machining laser beam (102) and for applying the workpiece (104) with the at least one machining laser beam (102), a feed unit (128) for controlling a position (x0,y0,z0) and / or and orientation (α0) and / or a movement status (v0, a0) of the workpiece (104) relative to the at least one machining laser beam (102), a detection unit (134) for determining a status of the feed unit (128), and a control unit (140) for controlling the phase adjustment unit (114), wherein the control unit (140) is designed to control the phase adjustment unit (114) according to the status of the feed unit (128) determined by the detection unit (134).

Description

[0001] Processing system and method for laser processing of a workpiece

[0002] The invention relates to a processing system and a method for laser processing a workpiece.

[0003] From DE 10 2020 201 161 A1 a device for combining a plurality of coherent laser beams is known, comprising a splitting device for splitting an input laser beam between the plurality of coherent laser beams, a plurality of phase adjusting devices for adjusting a respective phase of one of the coherent laser beams, and a beam combining device for combining the coherent laser beams emanating from a plurality of raster positions of a raster arrangement to form at least one combined laser beam, wherein the beam combining device has a microlens arrangement with exactly one microlens array for forming the at least one combined laser beam.

[0004] From WO 2017 / 125345 A1, a phase control system for controlling the relative phase of two laser beams to be coherently combined in a laser system which is intended to provide a phase-controlled sum laser beam is known.

[0005] From WO 2020 / 016824 A1 a method for determining phase shifts of several beams of a coherent beam combining device impinging on a target is known.

[0006] From EP 3 597 405 A1, a device for the additive production of three-dimensional objects by successively irradiating and solidifying layers of a building material by means of an energy beam is known, wherein an irradiation device is provided which is configured to generate at least two coherently stimulated energy beams, wherein the irradiation device comprises a modulation unit which is configured to combine the at least two energy beams into a combined energy beam and to adjust at least one combined beam property of the combined energy beam.

[0007] From WO 2019 / 092702 A2, a laser system is known, comprising a seed laser, a subsystem for splitting and combining laser beams, which receives an output from the seed laser and provides a combined laser output with noise, and a noise suppression subsystem, which serves to provide a noise suppression phase correction output based on the consideration of the noise at a noise sampling rate, wherein the subsystem for splitting and combining laser beams changes a phase of the combined laser output at a phase variation rate that exceeds the noise sampling rate.

[0008] The invention is based on the object of providing a processing system for laser processing of a workpiece as mentioned above, which enables versatile and flexible laser processing of the workpiece with dynamically adjustable beam parameters.

[0009] This object is achieved by a processing system mentioned above, comprising at least one laser beam source for providing a plurality of coherent laser beams, a phase adjustment device for adjusting a respective phase difference between the coherent laser beams, an amplification device for amplifying the coherent laser beams, wherein respective amplified coherent laser beams are formed by amplifying the respective coherent laser beams, a processing optics for combining the amplified coherent laser beams to form at least one processing laser beam and for applying the at least one processing laser beam to the workpiece, a feed device for controlling a position and / or an orientation and / or a movement state of the workpiece relative to the at least one processing laser beam, a detection device for determining a state of the feed device,and a control device for controlling the phase adjustment device, wherein the control device is configured to control the phase adjustment device depending on the state of the feed device determined by means of the detection device.

[0010] The processing system according to the invention enables the control of the phase adjustment device and thus the control of the phase differences between the coherent laser beams and amplified coherent laser beams depending on the state of the feed device, for example, depending on a position or speed of the at least one processing laser beam relative to the workpiece. By adjusting the phase differences between the coherent laser beams and amplified coherent laser beams, the properties and / or beam parameters of the at least one processing laser beam can be adjusted. The properties and / or beam parameters of the at least one processing laser beam can thus be adjusted depending on the state of the feed device.

[0011] By adjusting the respective phase difference between the coherent laser beams, various beam parameters and / or properties of the at least one processing laser beam can be adjusted. This allows, for example, the beam parameters and / or properties of the at least one processing laser beam to be dynamically adjusted depending on its position or speed relative to the workpiece. For example, the phase differences can be varied using the control device so that the processing laser beam has different beam parameters and / or properties in different spatial regions of the workpiece.

[0012] For example, by adjusting the respective phase difference between the coherent laser beams, the following beam parameters and / or properties of the existing processing laser beam or the existing processing laser beams can be set: a number of the existing processing laser beams - an intensity and / or polarization of the processing laser beam or the respective processing laser beams

[0013] - a spatial beam shape and / or a spatial beam profile of the processing laser beam or the respective processing laser beams

[0014] - a temporal sequence and / or a temporal pulse shape of pulses assigned to the processing laser beam or the respective processing laser beams

[0015] In particular, the processing optics are suitable for focusing the at least one processing laser beam onto and / or into the workpiece.

[0016] The feed device is particularly suitable for applying the processing laser beam to the workpiece at predetermined positions over time, and / or for applying predetermined orientations and / or motion states of the processing laser beam. For example, a trajectory along which the at least one processing laser beam is moved relative to the workpiece can be specified. The feed device can, for example, be programmed to apply the processing laser beam to the workpiece in a corresponding manner within the scope of a specific laser processing operation.

[0017] The amplification device may, for example, comprise a fiber amplifier, slab amplifier, rod amplifier or disc amplifier.

[0018] It can be provided that the amplification device has a frequency conversion stage or that a frequency conversion stage of the processing system is assigned to the amplification device.

[0019] In particular, a respective phase difference between the coherent laser beams and / or between the amplified coherent laser beams can be adjusted by means of the phase adjustment device. In particular, a change in the phase difference between the coherent laser beams carried out by means of the phase adjustment device causes a change in the phase difference between the corresponding amplified coherent laser beams. In particular, a minimum time interval with which the state of the feed device can be determined by means of the detection device or is determined during operation of the processing system lies in the range from 1 ns to 1 |JS. On this time scale, the phase adjustment device can be controlled, in particular by means of the control device, and the resulting adjustment of the respective phase difference between the coherent laser beams can take place.

[0020] For example, the amplification device is arranged downstream of the phase adjustment device. In particular, the phase adjustment device is then used to adjust the respective phase differences between the coherent laser beams before they are coupled into the amplification device. However, it is also possible, in principle, to arrange the phase adjustment device downstream of the amplification device.

[0021] The workpiece can, for example, be transparent, partially transparent, or opaque to a wavelength of the at least one processing laser beam. For example, the workpiece can comprise or consist of a ceramic material, a metal material, an organic material, a polymer material, a glass material, a crystal material, and / or a semiconductor material.

[0022] In particular, the state of the feed device is or includes a position of the workpiece relative to the at least one processing laser beam.

[0023] In particular, the state of the feed device is or includes an alignment of the workpiece relative to the at least one processing laser beam. For example, the state of the feed device is or includes an angle of incidence of the at least one processing laser beam relative to a reference plane of the workpiece.

[0024] In particular, the state of the feed device is or includes a movement state of the workpiece relative to the at least one processing laser beam, for example, a speed and / or acceleration of the workpiece relative to the at least one processing laser beam. The state of the feed device can in particular include the speed and / or acceleration with respect to a translation and / or rotation of the workpiece.

[0025] In particular, it can be provided that the control device is configured to adjust the respective phase difference between the coherent laser beams and / or the amplified coherent laser beams depending on the state of the feed device by controlling the phase adjustment device. In particular, the respective phase difference can be adjusted to a predetermined target value by means of the control device depending on the state of the feed device. This enables the adjustment of different properties of the at least one processing laser beam depending on the state of the feed device.

[0026] In particular, it can be provided that the state of the feed device that can be determined or is determined by the detection device is an actual state and / or a desired state of the feed device. The control of the phase adjustment device or the adjustment of the respective phase difference between the coherent laser beams can then be carried out depending on the determined actual state and / or desired state of the feed device.

[0027] The target state is understood to mean, in particular, a state of the feed device to be achieved based on current settings of the feed device, for example, a position or speed to be achieved of the at least one processing laser beam relative to the workpiece. The actual state is understood to mean, in particular, a measured and / or actual state of the feed device, preferably by means of a sensor device, for example, a measured position or speed of the at least one processing laser beam relative to the workpiece. It can be advantageous if the feed device has a scanner device, wherein the scanner device comprises, in particular, an acousto-optical deflector and / or a scanner mirror and / or a galvanometer scanner. The at least one output laser beam can thus be positioned and / or moved relative to the workpiece by means of the feed device.

[0028] It may be advantageous if the processing system includes a holder for arranging and / or securing the workpiece. In particular, the feed device is then associated with the holder and configured to move and / or align the workpiece arranged on the holder relative to the at least one processing laser beam.

[0029] The fact that the feed device is assigned to the holder and configured to move and / or align the workpiece arranged on the holder relative to the at least one processing laser beam does not necessarily mean that (as viewed in the laboratory system) the holder is actually spatially moved and / or shifted. It is also possible for other components of the processing system (as viewed in the laboratory system) to be spatially moved and / or shifted in order to move the at least one processing laser beam relative to the workpiece. For example, a gantry system can be provided for this purpose.

[0030] The said relative movement between the holder and the workpiece arranged thereon on the one hand and the at least one processing laser beam on the other hand can be realized by means of the feed device (viewed in the laboratory system), for example by moving the holder and / or by moving beam guidance components of the at least one processing laser beam and / or by moving the processing optics.

[0031] For example, the workpiece can be moved translationally and / or rotationally relative to the processing laser beam using the holder. The translational movement occurs, for example, along two and preferably along three spatial axes. The rotational movement occurs, for example, around at least two spatial axes.

[0032] It may be advantageous if the detection device comprises a sensor device for determining an actual state of the feed device, wherein the sensor device is in particular assigned to one or more components of the processing system that are configured to move and / or align the at least one processing laser beam relative to the workpiece. These components are assigned to the feed device and / or are part of the feed device, and by means of these components, the position and / or alignment and / or the movement state of the workpiece relative to the at least one processing laser beam can be adjusted.

[0033] For example, these components can be a scanner device of the feed device and / or an acousto-optical deflector of the feed device and / or a holder associated with the feed device for arranging the workpiece and / or a beam guide of the at least one processing laser beam and / or the processing optics.

[0034] For example, the sensor device comprises one or more sensor elements to determine the actual state of the feed device. This allows the actual state of the feed device to be determined technically simply and reliably.

[0035] In particular, the sensor device can comprise one or more sensor elements configured as position sensors and / or speed sensors. This allows, for example, positions or speeds on a scanner mirror and / or a galvanometer scanner and / or a mount to be detected in a technically simple manner in order to determine the actual state of the feed device.

[0036] Furthermore, the sensor device can, for example, comprise one or more sensor elements designed as temperature sensors. This allows, for example, in the case of an acousto-optical deflector, temperature-dependent deviations in the positions or speeds of the at least one processing laser beam relative to the workpiece to be determined.

[0037] It may be advantageous if the detection device is configured to read and / or process data from the feed device in order to determine the target state of the feed device. In particular, the data read and / or processed by the detection device are relevant for setting the target state of the feed device.

[0038] In particular, the read and / or processed data contain the target state of the feed device at a specific point in time.

[0039] In particular, it can be provided that the phase adjustment device is controlled by the control device based on a predefined assignment rule. In this case, it can be advantageous if the assignment rule has at least two different predefined parameter sets, which are selected depending on the state of the feed device determined by the detection device.

[0040] The assignment rule contains in particular an assignment of states of the feed device to phase differences to be set between the coherent laser beams.

[0041] A predefined parameter set is or contains a specification for the phase differences to be set between the respective coherent laser beams depending on the determined state of the feed device, ie a specification for which phase differences are set depending on a determined state of the feed device by means of the control device by controlling the phase setting device.

[0042] During operation of the processing system, the parameter sets are selected, in particular, on a minimum time scale in the range of 1 ns to 1 ps. In one variant, it may be provided that the assignment rule and / or the predefined parameter sets are not changed during operation of the processing system.

[0043] Alternatively, it is also possible for the assignment rule and / or the predefined parameter sets to be adapted and / or optimized during operation of the processing system, whereby this can be done in particular on a smallest time scale of 1 ps to 1 ps.

[0044] In particular, it can be provided that the coherent laser beams provided by the laser beam source are pulsed laser beams, in particular ultrashort pulse laser beams, and / or that the at least one processing laser beam is a pulsed laser beam, in particular an ultrashort pulse laser beam. Ultrashort pulse laser beams can be advantageously used for precise and low-damage micro-material processing.

[0045] In principle, it is also possible that the coherent laser beams and / or the at least one processing laser beam are continuous wave laser beams.

[0046] According to the invention, a method for laser processing a workpiece is provided, in which a plurality of coherent laser beams are provided, a respective phase difference between the coherent laser beams is adjusted, the coherent laser beams are amplified, wherein respective amplified coherent laser beams are formed by amplifying the respective coherent laser beams, the amplified coherent laser beams are combined to form the at least one processing laser beam, and the workpiece is exposed to the at least one processing laser beam, a position and / or an orientation and / or a movement state of the workpiece relative to the at least one processing laser beam is controlled by means of a feed device, a state of the feed device is determined by means of a detection device, and the phase adjustment device is controlled by means of a control device,The control device controls the phase adjustment device depending on the state of the feed device determined by the detection device. In particular, the method according to the invention has one or more further features and / or advantages of the processing system according to the invention. Advantageous embodiments of the method according to the invention have already been explained in connection with the processing system according to the invention. In particular, the method according to the invention is carried out by means of the processing system according to the invention and / or the processing system according to the invention is suitable for carrying out the method according to the invention.

[0047] The fact that a first device and / or a first element of the processing system is arranged downstream of a second device and / or a second element of the processing system is to be understood in the present case as meaning that the laser beams guided in the processing system, such as the input laser beam and / or the coherent laser beams and / or the amplified coherent laser beams, first strike the second device and / or the second element and then the first device and / or the first element. The second device and / or the second element is then arranged upstream of the first device and / or the first element. This information always relates to the main propagation direction of the laser beams guided through the processing system.

[0048] The following description of preferred embodiments, taken in conjunction with the drawings, serves to further explain the invention. They show:

[0049] Fig. 1 is a schematic representation of an embodiment of a processing system; and

[0050] Fig. 2 is a plan view of a workpiece arranged on a holder of the machining system.

[0051] Identical or functionally equivalent elements are provided with the same reference numerals throughout all figures. An exemplary embodiment of a processing system is shown schematically in Fig. 1 and designated by 100. The processing system 100 can provide at least one processing laser beam 102, which is intended for laser processing a workpiece 104.

[0052] In the embodiment shown in Fig. 1, the processing system 100 comprises a laser beam source 106 by means of which an input laser beam 108 is provided, wherein a plurality of coherent laser beams 110 are formed by splitting the input laser beam 108.

[0053] It is also possible in principle for multiple laser beam sources 106 to be provided to provide the coherent laser beams 110. For example, one or more coherent laser beams are then provided by a respective laser beam source 106.

[0054] For splitting the input laser beam 108 into a plurality of coherent laser beams 110, a splitting device 112 is provided, for example. Figure 1 shows, for example, three coherent laser beams 110, which are formed by splitting the input laser beam 108 by means of the splitting device 110.

[0055] The input laser beam 108 and / or the coherent laser beams 110 are, for example, pulsed laser beams and in particular ultrashort pulse laser beams.

[0056] The coherent laser beams 110 have, in particular, the same properties, such as the same wavelength and / or the same spectrum.

[0057] A phase adjustment device 114 is provided for adjusting a respective phase difference between the individual coherent laser beams 110. The phase adjustment device 114 comprises, in particular, a plurality of phase adjustment elements 116, wherein a specific phase adjustment element 116 can be used to adjust the phase of a coherent laser beam 110 assigned to this phase adjustment element 116. For example, a phase adjustment element 116 is assigned to several or all of the coherent laser beams 110.

[0058] In the case of N coherent laser beams 110, the

[0059] Phase adjustment device 114, for example N1 or N phase adjustment elements 116. This makes it possible, in particular, to set a respective phase difference between all existing coherent laser beams 110.

[0060] For technical details on combining coherent laser beams, please refer to the scientific publications "Coherent combination of ultrafast fiber amplifiers", Hanna, et al., Journal of Physics B: Atomic, Molecular and Optical Physics 49(6) (2016), 062004; "Performance scaling of laser amplifiers via coherent combination of ultrashort pulses", Klenke, Mensch und Buch Verlag; "Coherent beam combining with an ultrafast multicore Yb-doped fiber amplifier", Ramirez, et al., Optics Express 23(5), (2015), 5406-5416; and "Highly scalable femtosecond coherent beam combining demonstrated with 19 fibers", Le Dortz, et al., Optics Letters 42(10), (2017), 1887-1890.

[0061] To amplify the coherent laser beams 110, the processing system 100 comprises an amplification device 118 for amplifying the respective coherent laser beams 110. In particular, the amplification device 118 comprises a plurality of amplification elements 120, wherein, for example, a respective amplification element 120 is assigned to one of the coherent laser beams 110.

[0062] In the example shown in Fig. 1, the amplification device 118 or the amplification elements 120 are arranged downstream of the phase adjustment device 114 or the phase adjustment elements 116. For example, coherent laser beams 110 coupled out of the phase adjustment device 114 are coupled into the amplification device 118. In particular, the respective phase differences between the coherent laser beams 110 are adjusted by means of the phase adjustment device 114 before they are coupled into the amplification device 118. The coherent laser beams 110 amplified by the amplification device 118 are hereinafter referred to as amplified coherent laser beams 122. In the example shown, a number of existing coherent laser beams 110 corresponds to a number of existing amplified coherent laser beams 122.

[0063] To combine the amplified coherent laser beams 122 into the processing laser beam 102, the processing system 100 includes processing optics 124.

[0064] For example, amplified coherent laser beams 122 coupled out of the amplification device 118 are coupled into the processing optics 124. The processing laser beam 102 is then formed by combining these amplified coherent laser beams 122 by means of the processing optics 124.

[0065] For example, the processing optics 124 may comprise a diffractive optical element and / or a grating structure and / or a microlens array and / or a focusing element.

[0066] With regard to the technical details on the combination of coherent laser beams using diffractive optical elements, reference is made to the scientific publications "Coherent combination of ultrashort pulse beams using two diffractive optics", Zhou et al., Opt. Lett. 42, 4422-4425 (2017) and "Diffractive-optics-based beam combination of a phase-locked fiber laser array", Cheung et al., Opt. Lett. 33, 354-356 (2008). For the combination of coherent laser beams using one or more microlens arrays, reference is made to WO 2020 / 016336 A1 and DE 10 2020 201 161 A1.

[0067] The processing optics 124 are particularly configured to introduce and / or focus the formed processing laser beam 102 into the workpiece 102.

[0068] The workpiece 104 on which the laser processing is to be performed is arranged and / or secured and / or fixed, for example, to a holder 126 of the processing system 100. In particular, the workpiece 102 can be positioned and / or moved and / or tilted and / or rotated relative to the processing laser beam 102 by means of the holder 126.

[0069] For example, the workpiece 104 can be moved by means of the holder 126 in three different spatial directions and / or along three different spatial axes (indicated by arrows in Fig. 1, which correspond there, for example, to the x-, y-, and z-axes). For example, the workpiece 104 can then be rotatable about one or more of these spatial axes by means of the holder 126.

[0070] For example, it may be provided that one or more holders 126 are arranged and / or formed on a conveyor belt. For example, a plurality of workpieces 104 can be arranged one after the other on the conveyor belt in order to process them one after the other using the processing laser beam 102.

[0071] The processing system 100 has a feed device 128, by means of which a position xo, yo, zo and / or an orientation and / or a movement state of the workpiece 104 relative to the processing laser beam 102 can be controlled. In particular, a translation and / or a rotation of the workpiece 104 relative to the processing laser beam 102 can be controlled by means of the feed device 128.

[0072] The position xo,yo,zo or the movement state is to be understood in particular as a position or a movement state of a focus assigned to the processing laser beam 102 or a focus zone assigned to the processing laser beam 102 relative to the workpiece 104. Accordingly, the alignment can be understood as an alignment of the focus or the focus zone of the processing laser beam 102 relative to the workpiece 104.

[0073] The feed device 128 is particularly configured to introduce the at least one processing laser beam 102 into the workpiece 104 as a function of time at predetermined positions and / or with predetermined orientations and / or with predetermined motion states. The motion state of the workpiece 104 is understood to mean, for example, a speed vo and / or an acceleration ao of the workpiece 104 relative to the processing laser beam 102 with respect to translation or rotation.

[0074] The orientation of the workpiece 104 is understood, for example, to mean an angle of incidence ao of the processing laser beam 102 relative to a reference plane 130 of the workpiece 104, onto which the processing laser beam 102 is incident. In the example shown, the reference plane 130 is an outer side of the workpiece 104 onto which the processing laser beam 102 is incident.

[0075] In one embodiment, the feed device 128 is assigned to the holder 126 and / or the holder 126 is part of the feed device 128. The feed device 128 is then configured to move the holder 126 with the workpiece 104 arranged thereon relative to the processing laser beam 102, whereby the position and / or the orientation and / or the state of movement of the workpiece 104 relative to the processing laser beam 102 can be controlled by means of the feed device 128.

[0076] Alternatively or additionally, it may be provided that the feed device 128 is assigned to the processing optics 124 and / or a beam guide of the processing laser beam 102 of the processing system 100 in order to control the position, orientation, and / or movement state of the processing laser beam 102 relative to the workpiece 104. In particular, the processing optics 124 and / or the beam guide can then be controlled and / or moved by means of the feed device 128 in order to control the aforementioned position, orientation, and / or movement state.

[0077] It can be provided that the processing system 100 has a scanner device 132, by means of which the position, orientation, and / or movement state of the processing laser beam 102 relative to the workpiece 104 can be controlled. By means of the scanner device 132, the processing laser beam 102 can be positioned and / or moved and / or aligned relative to the workpiece 104. The scanner device 132 is arranged, for example, after a combination of the amplified coherent laser beams 122 by means of the processing optics 124 and / or before a focusing of the amplified coherent laser beams 122 by means of the processing optics 124 (indicated in Fig. 1). For example, the scanner device 132 is part of the processing optics 124 or integrated into the processing optics 124.

[0078] The scanner device 132 comprises, for example, an acousto-optical deflector and / or a scanner mirror and / or a galvanometer scanner.

[0079] The processing system 100 further comprises a detection device 134, by means of which a state of the feed device 128 can be determined. The state of the feed device 128 is to be understood in particular as the position xo, yo, zo, orientation ao and / or the movement state vo, ao of the workpiece 104 relative to the processing laser beam 102.

[0080] In particular, actual values ​​and / or target values ​​of the state of the feed device 128 can be determined by means of the detection device 134, ie actual states and / or target states of the feed device 128 can be determined.

[0081] To determine the target state of the feed device 128, the detection device 134 reads, for example, data from the feed device 128, on the basis of which the feed device 128 controls the workpiece 104 with regard to its position and / or its orientation and / or its state of movement relative to the processing laser beam 102 at a specific time. For this purpose, the detection device 134 is connected to the feed device 128 for signaling purposes (indicated in Fig. 1).

[0082] It is also possible in principle for the detection device 134 to be part of the feed device 128 and / or integrated into the feed device 128. The detection device 134 then has, in particular, the data of the feed device 128, on the basis of which the control of the workpiece 104 takes place at a specific time.

[0083] In any case, the detection device 134 provides the determined or existing data concerning the desired state of the feed device 128 for further processing.

[0084] To determine the actual state of the feed device 128, the detection device 134 may include a sensor device 136. This sensor device 136 can be used to measure the actual state of the feed device 128 with respect to the position, orientation, and / or movement state of the workpiece 104 relative to the processing laser beam 102.

[0085] The sensor device 136 is configured, for example, to capture measured values ​​relating to the holder 126 and / or the scanner device 132, from which the actual state of the feed device 128 can be determined. In particular, the sensor device 136 has one or more sensor elements 138, which are assigned, for example, to the holder 126 and / or the scanner device 132.

[0086] A specific sensor element 138 can be designed, for example, as a position sensor, orientation sensor, speed sensor, acceleration sensor or temperature sensor.

[0087] During operation of the processing system 100, it is provided that the phase adjustment device 114 is controlled in order to adjust the respective phase difference between the coherent laser beams 110 and / or the amplified coherent laser beams 122. In the example shown, the phase adjustment device 114 can be used to adjust the respective phase difference between the coherent laser beams 110 coupled into the amplification device 118, which effects a change and / or adjustment of the respective phase difference between the corresponding amplified coherent laser beams 122. To control the phase adjustment device 114, the processing system 100 has a control device 140, which is signal-effectively connected to the phase adjustment device 114. The control device 140 is configured to control the phase adjustment device 114 based on an assignment rule with specific control values.The assignment rule contains an assignment of target values ​​of the respective phase difference between the coherent laser beams 110 and / or amplified coherent laser beams 122 to specific control values. For example, the assignment rule is or includes an assignment table.

[0088] By means of the control device 140, the respective phase difference between the coherent laser beams 110 and / or the amplified coherent laser beams 122 can thus be adjusted to predetermined target values. This allows the processing laser beam 102 to be provided with predetermined properties for laser processing the workpiece 104.

[0089] Furthermore, the control device 140 is configured to control the phase adjustment device 114 during operation of the processing system 100 depending on the state, in particular the desired state and / or the actual state, of the feed device 128. In particular, the control device 140 is configured to adjust the respective phase difference between the coherent laser beams 110 and / or amplified coherent laser beams 122 depending on the state of the feed device 128.

[0090] The control device 140 is, for example, signal-effectively connected to the detection device 134 in order to obtain information regarding the state, in particular the desired state and / or the actual state, of the feed device 128 during operation of the processing system 100. Based on this information, the control device 140 then sets the respective phase difference between the coherent laser beams 110 or amplified coherent laser beams 122 to predetermined desired values ​​by appropriately controlling the phase adjustment device 114. For this purpose, for example, a further assignment rule can be provided, which contains an assignment of the state of the feed device to the desired desired values ​​of the respective phase difference.This further assignment rule can, for example, contain several predefined parameter sets for the phase differences to be set, which are selected depending on the state of the feed device 128.

[0091] A main propagation direction 142 of the coherent laser beams 110 and / or the amplified coherent laser beams 122 and / or the input laser beam 108 and / or the processing laser beam 102 through the processing system 100 is indicated by an arrow in Fig. 1.

[0092] The processing system 100 operates as follows:

[0093] During operation of the processing system 100, a plurality of coherent laser beams 110 are provided by the laser beam source 106. In the example shown in Fig. 1, an input laser beam 108 is first generated by the laser beam source 106, and this input laser beam 108 is split into the coherent laser beams 110 by the splitting device 112.

[0094] In the example shown, the provided coherent laser beams 110 then pass through the phase adjustment device 114 and subsequently the amplification device 118, wherein the amplified coherent laser beams 122 are formed by amplifying the coherent laser beams 110 by means of the amplification device 118.

[0095] The amplified coherent laser beams 122 are coupled into the processing optics 124 and combined and focused by means of the processing optics 124 to form the at least one processing laser beam 102. The processing laser beam 102 is introduced into the workpiece 104 and / or focused therein for laser processing.

[0096] To form the processing laser beam 102(s) with the desired properties, it is necessary to coordinate the respective phase differences between the amplified coherent laser beams 124 prior to their combination. For this purpose, these phase differences are adjusted by controlling the phase adjustment device 114 by means of the control device 140.

[0097] For laser processing of the workpiece 104, the at least one processing laser beam 102 and in particular its focus or focus zone is introduced into the workpiece 104, or aligned relative to it, or moved relative to it, as a function of time at predetermined positions xo, yo, zo and / or with predetermined orientations ao and / or motion states vo, ao. The corresponding control of the processing laser beam 102 relative to the workpiece 104 is carried out by means of the feed device 128, which is programmed accordingly, for example, for a specific laser processing operation of the workpiece 104.

[0098] As explained above, the control device 140 is configured to adjust the phase differences depending on the state of the feed device 128. For this purpose, the control device 140 receives corresponding information from the detection device 134.

[0099] The detection device 134 determines the state of the feed device 128, i.e. its actual state and / or desired state, by reading information from the feed device 128 itself and / or from the sensor elements 138 of the sensor device 136.

[0100] The state of the feed device 128 is to be understood in particular as the position xo,yo,zo and / or orientation ao and / or state of movement vo, ao of the workpiece 104 relative to the processing laser beam 102 acting on the workpiece 104.

[0101] For example, the workpiece may have four different regions Ai, A2, Bi, and B2, which are schematically shown in Fig. 2 and whose spatial boundaries are represented by the dashed lines. The feed device 128 may then be configured, for example, such that the workpiece 104 is sequentially exposed to the processing laser beam 102 in the regions Ai, Bi, B2, and A2 to perform a laser processing operation.

[0102] By detecting the current target position and / or actual position of the processing laser beam 102 by means of the detection device 134 and forwarding this information to the control device 140, the control device 140 can, for example, control the phase adjustment device 114 such that, depending on the respective area Ai, A2, Bi, B2 of the workpiece 104 in which the processing laser beam 102 is currently positioned, the respective phase differences between the amplified coherent laser beams 122 are set to different values. For example, it can be provided that a first predefined parameter set is set for the respective phase differences for the areas Ai and A2, and a second predefined parameter set is set for the areas Bi and B2.

[0103] By adjusting the respective phase differences, properties of the existing processing laser beams 102, such as their respective intensities, can be defined. In the example presented, the predefined parameter sets could, for example, be selected such that the processing laser beam 102 has different intensities in the areas Ai and A2, or Bi and B2.

[0104] List of reference symbols

[0105] Ai, A2 areas of the workpiece

[0106] BI, B2Areas of the workpiece xo,yo,zo Position

[0107] VO Speed ​​ao Acceleration ao Angle of attack

[0108] 100 processing system

[0109] 102 processing laser beam

[0110] 104 Workpiece

[0111] 106 Laser beam source

[0112] 108 input laser beam

[0113] 110 coherent laser beam

[0114] 112 Distribution device

[0115] 114 Phase adjustment device

[0116] 116 Phase adjustment element

[0117] 118 amplification device

[0118] 120 reinforcement element

[0119] 122 amplified coherent laser beams

[0120] 124 processing optics

[0121] 126 bracket

[0122] 128 Feed device

[0123] 130 Reference plane

[0124] 132 Scanner setup

[0125] 134 Detection device

[0126] 136 Sensor device

[0127] 138 Sensor element

[0128] 140 Control device

[0129] 142 Main propagation direction

Claims

Claims: Machining system for laser processing of a workpiece (104), comprising - at least one laser beam source (106) to provide a plurality of coherent laser beams (110), - a phase adjustment device (114) for adjusting a respective phase difference between the coherent laser beams (110), - an amplification device (118) for amplifying the coherent laser beams (110), wherein amplification of the respective coherent laser beams (110) results in the formation of respective amplified coherent laser beams (122), - a processing optic (124) for combining the amplified coherent laser beams (122) to form at least one processing laser beam (102) and for impinging the workpiece (104) with the at least one processing laser beam (102), - a feed device (128) for controlling a position (xo,yo,zo) and / or an orientation (oo) and / or a state of movement (vo, ao) of the workpiece (104) relative to the at least one processing laser beam (102), - a detection device (134) for determining the state of the feed device (128), and - a control device (140) for controlling the phase adjustment device (114), wherein the control device (140) is configured to control the phase adjustment device (114) depending on the state of the feed device (128) determined by means of the detection device (134). Machining system according to claim 1, characterized in that the state of the feed device (128) comprises at least one of the following: - a position (xo,yo,zo) of the workpiece (104) relative to the at least one processing laser beam (102); - an alignment of the workpiece (104) relative to the at least one processing laser beam (102), in particular an angle of inclination (‰) of the at least one processing laser beam (102) to a reference plane (130) of the workpiece (104); - a state of motion of the workpiece (104) relative to the at least one processing laser beam (102), in particular a velocity (vo) and / or acceleration (ao) of the workpiece (104) relative to the at least one processing laser beam (102); processing system according to claim 1 or 2, characterized in that the control device (140) is configured to adjust the respective phase difference between the coherent laser beams (110) and / or the amplified coherent laser beams (122) as a function of the state of the feed device (128) by controlling the phase adjustment device (114). Processing system according to one of the preceding claims, characterized in that the state of the feed device (128) determined by means of the detection device (134) is an actual state and / or a target state of the feed device (128).Machining system according to one of the preceding claims, characterized in that the feed device (128) comprises a scanner device (132) which in particular has an acousto-optic deflector and / or a scanner mirror and / or a galvanometer scanner. A machining system according to one of the preceding claims, characterized by a holder (126) for arranging and / or fixing the workpiece (104), wherein the feed device (128) is configured to move and / or align the workpiece (104) arranged on the holder (126) relative to the at least one machining laser beam (102). A machining system according to one of the preceding claims, characterized in that the detection device (134) has a sensor device (136) for determining an actual state of the feed device (128), wherein the sensor device (136) is in particular assigned to one or more components of the machining system which are configured to move and / or align the at least one machining laser beam (102) relative to the workpiece (104).Machining system according to one of the preceding claims, characterized in that the detection device (134) is configured to read and / or process data from the feed device (128) in order to determine the target state of the feed device (128). Machining system according to one of the preceding claims, characterized in that the phase adjustment device (114) is controlled by the control device (140) based on a predetermined assignment rule, wherein the assignment rule has, in particular, at least two different predefined parameter sets, which are selected depending on the state of the feed device (128) determined by the detection device (134).Processing system according to one of the preceding claims, characterized in that the coherent laser beams (110) provided by means of the laser beam source (106) are pulsed laser beams and in particular ultrashort pulse laser beams and / or that the at least one processing laser beam (102) is a pulsed laser beam and. in particular an ultrashort pulse laser beam. Method for laser processing of a workpiece (102), wherein - a plurality of coherent laser beams (110) is provided, - a respective phase difference between the coherent laser beams (110) is set, - the coherent laser beams (110) are amplified, whereby by amplifying the respective coherent laser beams (110) respective amplified coherent laser beams (122) are formed, - the enhanced coherent laser beams (122) to which at least one processing laser beam (102) is combined and the workpiece (104) is acted upon with the at least one processing laser beam (102), - a position (xo,yo,zo) and / or an orientation (oo) and / or a state of movement (vo, ao) of the workpiece (104) relative to which at least one processing laser beam (102) is controlled by means of a feed device (128), - a state of the feed device (128) is determined by means of a detection device (134), and - the phase adjustment device (114) is controlled by means of a control device (140), wherein the control device (140) controls the phase adjustment device (114) depending on the state of the feed device (128) determined by means of the detection device (134).

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