Laser processing system for generating multi-part asymmetrically varied laser pulses and method for processing material therewith

Abstract

The invention relates to a laser processing system (1) having at least one laser source (3, 4) for generating a plurality of mutually independent laser intensity distributions (5, 6). The laser processing system (1) comprises a control device (7) for controlling the laser power levels (P1, P2, 13, 14) and / or the beam quality levels (K1, K2, 14, 16) of the laser intensity distributions (5, 6) independently of one another. The laser processing system (1) is designed to vary the laser power levels (P1, P2, 13, 15) and / or the beam quality levels (K1, K2, 14, 16) of the laser intensity distributions (5, 6) differently from one another within each laser pulse by means of the control device (7). The invention also relates to a corresponding method for processing material (2) by means of corresponding laser radiation (5, 6).

Description

[0001] LASER PROCESSING SYSTEM FOR THE PRODUCTION OF MULTI-PART ASYMMETRICAL

[0002] VARIED LASER PULSE AND METHOD FOR MATERIAL PROCESSING WITH IT

[0003] The present invention relates to a laser processing system and a method for material processing using such a laser processing system.

[0004] Lasers can be used to great advantage in a wide variety of applications and fields. For example, laser-based material processing, such as welding or cutting, can offer advantages over other processing techniques. However, it can also present disadvantages or challenges, such as spatter from the processed material, the formation of unwanted cracks in the material, or less than optimal weld quality under all circumstances or conditions.

[0005] Previous approaches to optimization, such as adjusting the laser beam shape or laser power, cannot always completely avoid the aforementioned problems.

[0006] The object of the present invention is to enable improved laser-based material processing.

[0007] The problem is solved by the subject matter of the main claim and the dependent claim or independent claims. Further possible embodiments of the invention are specified in the dependent claims, the description, and the drawings. Features, advantages, and possible embodiments set forth in the description for one of the subject matter of the independent claims are to be regarded, at least analogously, as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as of any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the dependent claims.

[0008] The laser processing system according to the invention comprises at least one laser source for generating laser pulses, i.e., pulsed laser radiation. Depending on the requirements or application, various types of laser sources can be used, for example, a fiber laser, a solid-state laser, a gas laser, or the like. Likewise, the at least one laser source can be configured to generate laser pulses of different lengths, for example, to generate picosecond pulses, nanosecond pulses, ps pulses, fs pulses, or the like. The laser processing system according to the invention is configured to generate several independent laser intensity distributions at its output. In other words, this allows for the generation of multiple laser intensity distributions at one output of the laser processing system or in a working or processing area where a particular material or workpiece is processed by means of the generated laser pulses.When laser radiation can be processed or acted upon, two or more laser intensity distributions, i.e., laser points or laser areas, can be generated.

[0009] These independent laser intensity distributions can exhibit different properties and / or shapes, such as different profiles or cross-sectional areas. The independence of the laser intensity distributions can mean, for example, that they can be switched on and off independently by the laser processing system and / or have their parameters, properties, or characteristics adjusted or modified differently. In particular, the laser intensity distributions—at least on the material being processed or within the intended effective range of the laser radiation or laser pulses—can be spatially separated, either completely or partially, and / or only partially overlap. Thus, for example, the intensity maxima or focus areas of the laser intensity distributions can have different sizes and / or positions.For example, they can be located next to each other, or the intensity maximum or focus or focus area of ​​one of the laser intensity distributions can be surrounded by that of at least one other laser intensity distribution, or the like.

[0010] The intended processing or working area can encompass at least all laser intensity distributions, or at least their intensity maxima or focus areas. This working area can be a contiguous, compact region, which, depending on the requirements or application, may have a size of, for example, a few millimeters or centimeters. Thus, while the laser intensity distributions may be independent of each other in terms of their properties or control, they can nevertheless be directed or focused into the same, common working area by the laser processing system. For example, the laser intensity distributions can have at least essentially the same beam axes or beam axes that intersect within the working area.According to the invention, the laser processing system also includes a control unit for independently controlling or adjusting at least the laser power and / or the beam qualities of the various laser intensity distributions. The laser processing system is configured to vary the laser power and / or the beam qualities of the laser intensity distributions differently from one another within a single laser pulse by means of the control unit, i.e., by appropriate control. In other words, the laser power and / or the beam quality of one, more, or all of the different laser intensity distributions can be varied, i.e., changed, over a single laser pulse. Thus, different temporal profiles of at least their power and / or beam qualities can be generated for several or all of the laser intensity distributions within this laser pulse.This can also include a constant temporal evolution of one or more properties of one of the laser intensity distributions. The beam quality of a laser intensity distribution can, for example, denote, or be determined or characterized by, the beam quality of the respective corresponding laser pulse or laser pulse component immediately before the effective area, and / or the focus diameter or focus sharpness of the respective laser intensity distribution in the effective area or – viewed in the propagation direction – at the point or in the region of maximum focusing, and / or the Rayleigh length of the respective laser intensity distribution or the corresponding laser pulse or laser pulse component.

[0011] According to the present invention, multidimensional variation, in particular simultaneous and different variation or adjustment of the laser intensity distributions in several dimensions, i.e., sizes, properties, or parameters, within or during a laser pulse is possible. This allows, for example, not only the total power of the laser radiation directed onto the respective material to be processed to be varied within a laser pulse, but also its distribution across the various, and in particular, different laser intensity distributions. Compared to conventional approaches, the present invention thus allows for more flexible and comprehensive optimization. Depending on the application, various advantages can be achieved.For example, the present invention can be used to improve the quality of laser welds and / or prevent or reduce cracking in a material during or after laser processing and / or prevent or reduce unwanted spatter from the processed material, or similar effects. To enable simple, reliable, and consistent control and material processing, a defined, i.e., predetermined, time window can be specified for each laser pulse. It can then be specified, for example, as a boundary condition for controlling the laser intensity distributions that they must disappear at the beginning and end of the respective time window, i.e., exhibit an intensity or power of zero.Within the time window, however, the laser intensity distributions can vary as described, exhibiting different profiles in one or more properties or parameters. This allows for the temporal synchronization of the laser intensity distributions with respect to their timing across multiple pulses, particularly when the different laser intensity distributions have different lengths or activity times with non-zero intensity or power, i.e., different start times and / or times within the common time window. In other words, this prevents an unwanted temporal shift in the activity times of the different laser intensity distributions relative to each other, provided that the different laser intensity distributions have different pause or inactivity times between two pulses.Activity periods or different timing of activity times are planned.

[0012] The laser processing system according to the invention can include further components, such as an electrical supply and / or at least one laser amplifier and / or processing optics and / or a beam splitter and / or a beam trap and / or a displacement mechanism for moving the material to be processed or for generating relative movement between the material to be processed and the at least one laser source or an output of the laser processing system and / or the like. For example, when using a fiber laser or guiding the laser intensity distributions in a fiber, i.e., an optical waveguide or fiber optic cable, processing optics can project the end of the fiber, i.e., the laser intensity distributions present there, onto the material to be processed or acted upon, or onto the predetermined working or processing area.Similarly, the processing optics can be set up to focus the laser intensity distributions or to shift their focus positions or the like.

[0013] In one possible embodiment of the present invention, the control unit directly controls an input of the at least one laser source, at least for varying the laser power. In other words, the laser processing system can be configured accordingly, i.e., the control unit can be configured accordingly and coupled to the at least one laser source or its voltage or power supply, or the like. For example, the supply or input power of the at least one laser source can be controlled by means of an electrical function generator. This generator can be controlled by the control unit or be part of the control unit. The embodiment of the present invention proposed here can enable simple, effective, and efficient control or adjustment of the properties of the laser intensity distributions.This also makes it possible to achieve a particularly compact, cost-effective and robust overall design for the laser processing system.

[0014] Alternatively, for example, at least one controllable optical element could be arranged within a predetermined, intended light path or beam path within the laser processing system to controllably influence the described properties of the laser intensity distributions, and this element could then be controlled accordingly by means of the control unit. Such an optical element could, for example, be or comprise an electro-optically active material, an optical modulator, or the like.

[0015] In a further possible embodiment of the present invention, the laser processing system for guiding the laser pulses comprises at least one optical waveguide with several separate light-guiding regions, each for guiding one of the laser intensity distributions. In particular, the optical waveguide can have a central core region for guiding a first laser intensity distribution and at least one surrounding ring region for guiding a second or further laser intensity distribution. In other words, the optical waveguide can be a multi-core, 2-in-1, or n-in-1 optical fiber. The different laser intensity distributions can thus be generated separately or independently of one another and coupled into one of the light-guiding regions.Using such an optical waveguide, the various laser intensity distributions can be guided relative to each other particularly easily, reliably, and in a highly precise and consistent arrangement. This allows for a simple achievement of consistent behavior and performance of the laser processing system, making it particularly robust. In a further possible embodiment of the present invention, the laser processing system comprises several laser sources and a combination device for combining the laser radiation generated by these laser sources. The individual laser sources can be controlled individually, i.e., independently of each other, for example, by means of the control unit. Each individual laser source can generate precisely one of the different laser intensity distributions. This allows the various laser sources to be individually optimized.The combining device can be, for example, a fiber combiner for combining or splicing multiple optical waveguides, a beam splitter, or the like. The combining device can be arranged along a defined or predetermined beam path of the laser pulses or laser radiation within the laser processing system, between the laser sources and the output, in particular an output-side processing and / or focusing optic. Using the combining device, the laser radiation from the various laser sources can, for example, be superimposed in a predetermined manner or directed or coupled into a single common optical waveguide, or the like.This allows, on the one hand, a flexible design of the laser processing system, for example with regard to the arrangement of the individual laser sources relative to each other, and on the other hand, a robust and consistent laser output behavior or a robust and consistent performance of the laser processing system.

[0016] If the combination device includes a beam splitter, such as one that can be optically controlled, it allows laser radiation from different laser sources to be distributed or coupled into different light-guiding areas of a multi-core optical waveguide. The proposed use of multiple laser sources enables even greater flexibility in controlling and adjusting the laser intensity distributions, the laser output behavior, and the overall performance of the laser processing system. For example, different types of laser sources can be used for the various laser intensity distributions, and these can be individually and independently selected and optimized for different tasks or requirements.Furthermore, this allows the power of each laser intensity distribution to be easily adjusted between 0% and 100% of the maximum laser power of a laser source, i.e., without loss of efficiency or without leaving any of the generated laser radiation unused. In a possible embodiment of the present invention, the multiple laser sources are each configured to generate one of the laser intensity distributions. In addition, the common optical waveguide is arranged to guide one, and in particular exactly one, of the different laser intensity distributions in each of its various light-guiding areas. This allows the different laser intensity distributions to be controlled or varied with particular precision and independently of one another. Ultimately, this can lead to particularly precise and optimized control.Adjusting the properties of the different laser intensity distributions and thus ultimately enabling particularly precise and high-quality material processing.

[0017] In a further possible embodiment of the present invention, the laser processing system additionally comprises at least one continuous-wave laser source. Here, the laser processing system is configured to simultaneously direct or focus pulsed laser radiation (i.e., the laser pulses) generated by the at least one pulsed laser source and continuous laser radiation generated by the continuous-wave laser source into the same predetermined working area or processing area of ​​the laser processing system. Thus, the laser processing system can be configured to process or treat the respective material with the continuous laser radiation and also with the laser pulses that are temporarily superimposed on it. The laser pulses and the continuous laser radiation can have different properties and, in particular, can be parameterized or controlled independently of one another.The proposed embodiment of the present invention allows, for example, several different processing functions to be performed using the same laser processing system, or even in the same processing operation or pass. For instance, continuous laser radiation and laser pulses can be used in a single pass to derust a metallic material and simultaneously engrave, weld, drill, cut, or perform similar operations. This further increases the flexibility of the laser processing system.

[0018] In a further possible embodiment of the present invention, the laser processing system or its control unit is configured to temporarily reduce the output laser power of at least one of the laser intensity distributions to at least essentially zero in a temporally central region of a laser pulse. In other words, the corresponding laser intensity distribution within a pulse, for example within the corresponding predetermined time window for the laser pulse mentioned elsewhere, can initially be greater than zero, then drop to at least essentially zero, and subsequently be greater than zero again. For this purpose, the control unit can, for example, be configured or designed for correspondingly fast control or switching relative to the predetermined total length of the laser pulses.The proposed embodiment of the present invention allows for even greater flexibility, as well as further adaptation and optimization of the behavior and effect of the emitted laser radiation. This, in turn, further improves the precision and quality of the material processing results achievable with the laser processing system.

[0019] In a further possible embodiment of the present invention, the laser processing system or its control unit is configured to asymmetrically vary the temporal profile of at least one or more of the aforementioned properties of at least one or more of the laser intensity distributions, in particular their laser power and / or their beam quality, relative to the temporal midpoint of each laser pulse over the entire duration of that laser pulse, i.e., over its total temporal length or the corresponding time window mentioned elsewhere. In other words, the laser processing system or its control unit can be configured to generate or adjust a temporally asymmetric profile within a laser pulse with respect to at least one property of at least one of the laser intensity distributions.This allows, for example, the consideration or compensation of asymmetric changes in the properties or state of the material being processed during a laser pulse. For instance, the laser power of a laser intensity distribution might be relatively high or increase rapidly at the beginning of the laser pulse and then decrease towards the end, or reduce via a longer and shallower ramp compared to the initial increase. Similarly, the beam quality, i.e., the size of the laser intensity distribution, might be relatively small or the focus diameter relatively large at the beginning of the laser pulse. This can then be modified, for example, in the middle of the laser pulse, resulting in a narrower or sharper focus or a more compact laser intensity distribution.

[0020] This allows, for example, consideration of the fact that the material being processed may initially have a relatively low temperature and be solid, while towards the end of the laser pulse, the material may have a higher temperature and be at least partially melted. Similarly, the temporally asymmetrical modification of one or more of the laser intensity distributions proposed here can achieve, for example, an optimized contour or edge quality of the material being processed in the processing area and / or an optimized temperature profile within the material. The proposed design can therefore enable further improved flexibility and quality in material processing.

[0021] In a further possible embodiment of the present invention, the laser processing system is configured to generate several laser intensity distributions with different wavelengths and / or to generate different temporal profiles of the wavelengths or spectra of several laser intensity distributions within or across a single laser pulse. For this purpose, the laser processing system can, for example, comprise several laser sources capable of generating laser radiation of different wavelengths and arranged to generate or feed one of the laser intensity distributions, i.e., for example, a specific light-guiding region of an optical waveguide. Thus, for example, these multiple laser sources can be arranged to couple their laser radiation of different wavelengths into the same light-guiding region of an optical waveguide mentioned elsewhere.For example, a different selection or combination of laser sources can be used to generate the laser intensity distribution in the first time segment of a laser pulse than in a second time segment of the same laser pulse. This further improves the flexibility of the laser processing system and the resulting processing quality. This is because different laser wavelengths can produce different effects in a given material being processed and / or, for example, penetrate the material to different depths. By appropriately adjusting or varying the wavelength profile, a specific three-dimensional temperature distribution can be generated within the material being processed, and / or at different times or in different phases, specific temperature distributions can be achieved.In different sequences, chemical bonds in different depth regions of the material being processed and / or different chemical components of the material being processed can be prioritized and influenced, or the like. Instead of using several correspondingly different laser sources, a controllable optical device for wavelength conversion or the like can also be used. In a further possible embodiment of the present invention, the laser processing system or its control unit is configured to vary the output laser radiation, i.e., the laser radiation emitted by the laser processing system, over several laser pulses. In other words, the laser processing system can be configured to generate different variations within the laser pulse, or...The profiles of the aforementioned quantities or properties, such as laser power and / or beam quality and / or wavelength or spectrum and / or the combination of pulsed and continuous laser radiation, can be measured in successively generated laser pulses or across multiple corresponding time windows. This allows for variation both within a single laser pulse and across multiple laser pulses, thus enabling the realization of variations on two different timescales. This can lead to increased flexibility and further optimization of material processing. For example, more complex processing geometries can be generated, or several different areas of a material or workpiece can be individually optimized and processed in a single pass.This also allows, for example, a response to changes in the material being processed that occur during processing over several laser pulses or corresponding time windows. For instance, a first type or configuration of laser pulses can be used to create a weld seam, and a second type or configuration of laser pulses can be used when this weld seam intersects itself, for example, along a circular path or similar. Thus, it can be taken into account or compensated for the fact that the material being processed may have different properties in a previously processed area than in an unprocessed area.

[0022] In a further possible embodiment of the present invention, the laser processing system is configured or designed for laser welding. This can mean, for example, that the laser processing system can generate laser radiation with a maximum or average power that is sufficient or suitable for welding, for example, metallic materials. For instance, the laser processing system can be configured or designed to generate maximum or average laser powers in the range of several kilowatts. Laser welding can be an application in which the described advantages can be particularly effective and beneficial. The present invention also relates to a method for processing, in particular laser welding, material using laser radiation. In the method according to the invention, the material to be processed is heated in a predetermined effective or...The processing area of ​​the laser processing system according to the invention is arranged. Pulsed laser radiation with multiple laser intensity distributions, which within a single laser pulse exhibit different temporal profiles in at least one property, particularly in their laser power and / or beam quality, is then generated by means of this laser processing system and directed into the predetermined working or processing area, i.e., onto the material to be processed. Further control measures, processes, or sequences mentioned in connection with the laser processing system according to the invention can constitute further, optionally, process steps of the method according to the invention. Accordingly, the laser processing system according to the invention can be configured for at least partial, in particular automatic or semi-automatic, application or execution of the method according to the invention.The laser processing system can include, for example as part of the control unit, a process unit such as a microprocessor, microchip, microcontroller, or similar device, and a connected computer-readable data storage device. This computer-readable data storage device can then contain a corresponding operating or computer program that encodes or implements the relevant process steps, actions, sequences, or control instructions and can be executed by the process unit to carry out the corresponding process or to effect its execution.

[0023] The described control or variation of the laser intensity distributions or their properties can be carried out, for example, according to a program or scheme predefined before the start of material processing. This can enable consistent and precise material processing with minimal effort. Likewise, the control or variation can be performed automatically and dynamically during material processing, or adjusted or set as needed. For this purpose, the material being processed, or the corresponding working or processing area, can be automatically monitored by sensors during processing. The corresponding sensor data can then serve as feedback signals in a control loop, depending on which one or more of the aforementioned properties of the laser intensity distributions can be automatically controlled or varied, i.e., adjusted.This allows for dynamic adjustments to individual characteristics or reactions of the material being processed. This, in turn, can ultimately lead to further improved processing quality.

[0024] Further features of the invention may become apparent from the following description of the figures and from the drawings. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and / or in the figures themselves, can be used not only in the combinations specified, but also in other combinations or individually, without departing from the scope of the invention.

[0025] The drawing shows, in the single figure, a partial schematic representation of a laser processing system for optimized material processing.

[0026] Fig. 1 shows a partial schematic representation illustrating a laser processing system 1 for laser-based processing of a workpiece 2. The laser processing system 1 comprises, by way of example, a first laser source 3 and a second laser source 4. These laser sources 3 and 4 can generate different laser intensity distributions, i.e., differently shaped and / or parameterized laser pulses. In this example, the first laser source 3 can generate, for example, a substantially point-like or circular internal laser intensity distribution, which may, for example, have a Gaussian or tophat profile. This internal laser intensity distribution is referred to here as the core beam 5. The second laser source 4, on the other hand, can generate an annular laser intensity distribution, which is referred to here as the ring beam 6 and which can surround the core beam 5 in a ring shape.

[0027] To generate the various laser intensity distributions in a manner that is temporally coordinated with each other and with regard to their shapes or properties, and tailored to a specific processing task, the laser processing system 1 includes a correspondingly configured control unit 7. The control unit 7 can control or adjust the laser light sources 3, 4 to generate the desired laser intensity distributions, in this case, the core beam 5 and the ring beam 6. Depending on the application, requirements, or capabilities of the laser sources 3, 4 used, the control unit 7 can also control them to generate other or differently shaped laser intensity distributions and / or other combinations of laser intensity distributions. The control unit 7 can, for example, include an electrical or electronic function generator and / or modulation generator to generate or specify corresponding setpoint values ​​or laser pulse shapes for the laser sources 3, 4.During operation of laser processing system 1, the control unit 7 can be programmed with a fixed set of settings. Alternatively, laser processing system 1 and / or control unit 7 can be automatically or manually adjusted or scaled. This allows, for example, the generated laser intensity distributions or corresponding laser pulse shapes to be scaled temporally and / or in amplitude, i.e., stretched or compressed, as required.

[0028] The laser radiation generated by laser sources 3 and 4 can be guided, for example, via individual optical waveguides 8 within the laser processing system 1 to a beam combiner 9. In the beam combiner 9, the individual laser intensity distributions can be combined or superimposed. In this case, the individual laser intensity distributions of the different laser sources 3 and 4 can be coupled into a common optical waveguide 10 in or through the beam combiner 9. This optical waveguide 10 can be a multi-core fiber, i.e., it can have several separate light-guiding regions. For example, the core beam 5 generated by the first laser source 3 can be coupled into a central light-guiding region, and the ring beam 6 generated by the second laser source 4 can be coupled into a surrounding annular light-guiding region of the optical waveguide 10.

[0029] The laser processing system 1 also has an output-side processing optic 11. The individual laser intensity distributions can be guided to this optic within the collecting optical waveguide 10. The processing optic 11, which can include one or more optical elements such as one or more lenses or the like, can direct or focus the laser intensity distributions into a predefined common processing or working area 12. The workpiece 2 to be processed is located there.

[0030] To achieve the best possible processing result, the laser intensity distributions can be varied independently of one another within a laser pulse with respect to several properties. For this purpose, the laser sources 3 and 4 can be controlled accordingly by the control unit 7. For further illustration, exemplary and schematic curves of laser powers P1 and P2 and beam qualities K1 and K2 of the core beam 5 and the ring beam 6 over time t for a laser pulse are plotted here in the control unit 7. A first power curve 13 shows that the laser power P1 of the core beam 5 varies over the course of the laser pulse. This first power curve 13 is asymmetric with respect to the midpoint of the laser pulse. The laser power P1 thus increases at the beginning of the laser pulse and decreases again towards the end of the laser pulse, with the slopes of the increase and decrease having different magnitudes.An exemplary and schematic representation of the beam quality profile 14 of the core beam 5 for the same laser pulse is also shown here. It can be seen that the beam quality K1, i.e., for example, the narrowness or sharpness of the focusing of the core beam 5 in the effective area 12, also varies over the laser pulse, i.e., it is not constant.

[0031] Similarly, a second power profile 15 and a second beam quality profile 16 for the ring beam 6 are shown schematically and as examples for the same laser pulse. It can be seen that the second power profile 15 differs from the first power profile 13, and the second beam quality profile 16 also differs from the first beam quality profile 14.

[0032] The control unit 7 can, for example, generate multidimensional or multidimensionally varied pulse shapes via a suitably configured multiple setpoint generator. These pulse shapes can be adjusted with respect to the power of the laser intensity distributions, the power distribution between different laser intensity distributions, the beam quality, and / or other properties or parameters. This allows for a temporally and spatially optimized laser power input into the workpiece 2 during a laser pulse. For example, in laser welding, an initial learning phase with a relatively high spatial power input (i.e., relatively low beam quality) and a gradually increasing laser power—to prevent spatter caused by localized overheating—can be used or set. This can then transition into the melting of the workpiece.For materials to be welded, a higher beam quality (i.e., a sharper focus) and relatively high laser power are used. Finally, the process can be switched back to a larger spatial power input (i.e., lower beam quality) with decreasing laser power, thus preventing, for example, the unwanted formation of cracks due to excessively rapid cooling. However, depending on the requirements or application, numerous other profiles and variations are also possible.

[0033] Overall, the described examples show how a laser in a pulse-shape mode with multidimensional beam or path distributions that vary or progress independently of each other or differently relative to each other can be used.

[0034] Laser pulse shapes can be realized and applied.

[0035] REFERENCE MARK LIST

[0036] 1 laser processing system

[0037] 2 workpieces

[0038] 3 first laser source

[0039] 4 second laser source

[0040] 5 core beam

[0041] 6 ring beam

[0042] 7 Control unit

[0043] 8 individual optical waveguides

[0044] 9 beam combinations

[0045] 10 Collecting optical waveguides

[0046] 11 Processing optics

[0047] 12 Area of ​​influence

[0048] 13 first performance history

[0049] 14 first beam quality progression

[0050] 15 second performance history

[0051] 16 second beam quality profile

[0052] P1, P2 Laser power K1, K2 Beam quality t Time

Claims

PATENT CLAIMS 1. Laser processing system (1) comprising at least one laser source (3, 4) for generating laser pulses and configured to generate several independent laser intensity distributions (5, 6) at the output, wherein the laser processing system (1) comprises a control unit (7) for independently controlling the laser powers (P1, P2, 13, 15) and / or the beam qualities (K1, K2, 14, 16) of the laser intensity distributions (5, 6) and is configured to vary the laser powers (P1, P2, 13, 15) and / or beam qualities (K1, K2, 14, 16) of the laser intensity distributions (5, 6) differently from each other by means of the control unit (7) within each laser pulse.

2. Laser processing system (1) according to claim 1 , characterized in that the control unit (7) directly controls an input of the at least one laser source (3, 4) at least for varying the laser power (P1, P2, 13, 15).

3. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) has an optical waveguide (10) with several light guiding areas, in particular a central core area and at least one ring area surrounding it, for guiding each of the laser intensity distributions (5, 6).

4. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) has several laser sources (3, 4) and a combining device (9) for combining the laser radiation (5, 6) generated by the laser sources (3, 4).

5. Laser processing system (1) according to claims 3 and 4, characterized in that the laser sources (3, 4) are each configured to generate one of the laser intensity distributions (5, 6) and the optical waveguide (10) is arranged to be in the to guide one, in particular exactly one, of the laser intensity distributions (5, 6) to each of the different light guidance areas.

6. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) additionally has a continuous wave laser source and is configured to simultaneously direct the laser pulses and continuous laser radiation generated by means of the continuous wave laser source into the same predetermined processing area (12).

7. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) is configured to temporarily reduce the laser power (P1 , P2, 13, 15) of at least one of the laser intensity distributions (5, 6) to zero in a temporally central region of a laser pulse.

8. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) is configured to vary the temporal profile of the laser power (P1, P2, 13, 15) and / or the beam quality (K1 , K2, 14, 16) of at least one of the laser intensity distributions (5, 6) asymmetrically over the course of a laser pulse with respect to the temporal midpoint of that laser pulse.

9. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) is configured to generate several of the laser intensity distributions (5, 6) with different wavelengths and / or to generate different temporal profiles of the wavelengths of several of the laser intensity distributions (5, 6) within a laser pulse.

10. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) is configured to vary the laser radiation (5, 6) emitted by the laser processing system (1) over several laser pulses.

11. Laser processing system (1) according to one of the preceding claims, characterized in that the laser processing system (1) is configured for laser welding.

12. Method for processing, in particular laser welding, of material (2) by means of Laser radiation, whereby - the material to be processed (2) is arranged in a predetermined processing area (12) of the laser processing system (1) according to one of the preceding claims, and - pulsed laser radiation (5, 6) with several laser intensity distributions (5, 6) varying differently from each other within a laser pulse in at least one property (P1 , P2, K1, K2) is generated by means of the laser processing system (1) and directed onto the material to be processed (2).

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