Laser system for generating at least one segmented focused beam

Abstract

Laser system (1) for generating at least one segmented focus beam (FS) comprising a first to nth focus segment (FS1 to FSn) comprising at least one preferably fiber-coupled laser unit (2) for generating a laser beam (LS) with different wavelengths (w1 to wn) and a processing optic (3) connected thereto, wherein the processing optic (3) comprises at least a collimation optic (5), a beam deflection device (6), a beam shaping optic (7) and a focusing optic (8) which are arranged successively in the propagation direction (z) of the laser beam (LS), wherein the laser beam (LS) generated by the laser unit (2) is deflected by means of the beam deflection device (6) into first to nth partial laser beams (TS1 to TSn) each with a different wavelength (w1 to wn) and beam direction (SR1 to SRn) and wherein by means of the beam shaping and focusing optic (7,8) the first to nth partial laser beams (TS1 to TSn) are transformed into the first to nth focus segment (FS1 to FSn) of the segmented focus beam (FS), characterized in that the steel forming optics (7) are formed by at least one first and second cylindrical lens field (2.1, 2.2), which are arranged one behind the other and at an angle to each other in the propagation direction (z) and are aligned orthogonally to each other for two-dimensional beam homogenization.

Description

[0001] The invention relates to a laser system for generating at least one segmented focus radiation according to the preamble of claim 1.

[0002] Laser systems, particularly high-power laser systems for generating application-specific laser radiation in a processing plane, hereinafter referred to as focus radiation, are generally known in terms of their design and operation. Such laser systems are used particularly in industrial production processes.

[0003] A laser system typically comprises at least one laser light source for generating laser radiation and a processing optics unit arranged downstream of the laser light source in the beam path of the generated laser radiation for generating focused radiation with an application-specific focus geometry in a processing plane. The laser light source can, for example, be formed by a diode laser unit consisting of one or more stacks of diode laser bars, each diode laser bar comprising a plurality of laser diodes arranged parallel to one another in a plane. Such diode laser units are designed to generate laser radiation with high power or intensity and are therefore frequently used in the field of industrial materials processing.

[0004] Such laser units can also be directly coupled to an optical fiber. The generated laser radiation is coupled directly into an optical fiber and transmitted via this fiber to a processing location, preferably located remotely from the laser unit, or to the processing optics located there. Such laser units are also referred to as fiber-coupled laser units.

[0005] The beam shaping of the laser radiation provided by the laser unit is carried out by the processing optics, which are located downstream of the laser unit in the beam path. This typically consists of an arrangement of several optical components, in particular various lens and / or mirror elements.

[0006] The processing optics comprise, for example, at least one collimating optic, one beam-shaping optic, and / or one focusing optic. The focusing optics bundle or focus the laser radiation shaped by the beam-shaping optic in the processing plane, thereby generating the focused radiation available for use in the processing area. The focused radiation impinging on the workpiece is also referred to as a "laser spot" due to its dimensions. The focused radiation often has an application-specific focus geometry. Due to the radiation characteristics of the diode laser unit, in the case of diode laser radiation, the generated focus geometry of the laser spot or the focused radiation is, for example, linear or rectangular.

[0007] In industrial production processes, high-quality glass fiber or carbon fiber composite parts can be manufactured through automated tape laying or tape winding. To increase the adhesion of the tape to a partially finished component, the tape is melted onto the surface of the partially finished component by heating the flat connection area. For this purpose, the flat connection area is exposed to focused radiation generated by a laser system, thereby heating it.

[0008] In another industrial application, surface sections of a workpiece can be hardened by exposure to appropriately dimensioned focused radiation.

[0009] In such large-area laser applications, it may be necessary to generate spatially highly varying intensity distributions on the component or workpiece. The focus geometry of the focused radiation can, for example, be a line composed of n number of focus segments. During the production process, it is necessary to regulate or control the intensity or power of each focus segment separately.

[0010] To generate such segmented focus radiation with focus segments of different intensities, so-called direct laser beam systems are currently used. These can be individually controlled and are often modular in design. A direct laser beam system generates a focus segment of the segmented focus radiation, preferably with a linear or rectangular focus geometry and a predetermined intensity. Such direct laser beam systems are known, for example, from EP 3 848 188 A1 or US 2021 / 0 206 123 A1.

[0011] To generate the desired segmented focus radiation with varying intensity distribution, multiple direct laser beam systems are required. These are arranged in a cascade and provide focus radiation with several adjoining focus segments with different power levels or intensities. A disadvantage is the high installation space required due to the cascading, which is typically not available to this extent in existing production systems. Another disadvantage of such direct laser beam systems is the mandatory short working distance between the processing optics and the workpiece, which further complicates integration into existing production systems. Other disadvantages are the long cable runs for electrical supply lines and the high cooling water requirements for the direct laser beam systems.

[0012] DE 10 2020 125 425 A1 discloses a device for scanning a target plane with multiple laser beams, which uses a focusing arrangement for focusing the laser beams onto the target plane and a scanning device common to all laser beams. The device comprises an arrangement for combining the laser beams, which is arranged between the laser beam sources or connections for optical fibers and the scanning device and has one or more movable deflection mirrors with which the relative position of the laser beams in the target plane can be dynamically changed in one or two dimensions.

[0013] WO 2014 / 083160 A2 discloses a device and method for laser material processing using multiple laser beam sources, wherein the laser beam sources emit laser beams with different wavelengths. The device comprises multiple imaging optics, a collimating optic, and a focusing optic. The beam imaging optics are designed to adjust the beam paths of the respectively assigned laser beams with different wavelengths. After leaving the imaging optics, the laser beams are superimposed via a beam superposition device, and the superimposed laser beams are imaged onto a workpiece via a downstream imaging optic, so that multiple focal points are created on the workpiece at the focus of the imaging optics. The arrangement of the focal points on the workpiece can be adjusted using the beam imaging optics.By means of an electronic control device, the respective powers of the laser beams can be varied at high frequency in order to vary the intensities of the respective focal points in the focus of the imaging optics in a predetermined manner.

[0014] Based on this, the invention is based on the object of providing a laser system for generating segmented focus radiation, which eliminates the disadvantages described above and, in particular, enables focus radiation with a spatially and / or temporally variable intensity distribution to be generated. This object is achieved according to the invention by a laser system according to claim 1 and a processing optics system for use in a laser system according to the invention according to claim 12.

[0015] Advantageous further developments, details and embodiments of the invention emerge from the dependent claims, the description and the drawings.

[0016] The essential aspect of the laser system according to the invention for generating segmented focus radiation is that the laser radiation generated by the laser unit is deflected by means of the beam deflection device into first to n-th partial laser beams, each with a different wavelength and beam direction, and that the first to n-th partial laser beams are transformed into the first to n-th focus segment of the segmented focus radiation by means of the beam shaping and focusing optics, wherein the beam shaping optics is formed by at least a first and second cylindrical lens field, which are arranged one behind the other in the propagation direction and spaced from one another and are aligned orthogonally to one another for two-dimensional beam homogenization.Starting with laser radiation with different wavelengths, the radiation components of the laser radiation having an assigned wavelength are particularly advantageously used as an individually controllable and adjustable radiation channel in order to provide a temporally and / or spatially adjustable intensity distribution of a segmented focus radiation in the processing plane. Particularly advantageous is the free adjustment of the local position of the individual focus segments by appropriately deflecting the beam direction relative to the optical axis of the beam deflection device, depending on an assigned angular offset. This enables one- and two-dimensional segmentation of the focus radiation in the processing plane. The processing optics can advantageously be used with a greater working distance than with the prior art.

[0017] Furthermore, the spatial position of the first to nth focus segments in the processing plane and / or the intensity of the first to nth focus segments in the processing plane can be adjusted independently and / or separately from one another. Advantageously, in addition to a spatial superposition of two or more focus segments in the processing plane, a wavelength-dependent adjustment of the output intensity in the laser source generating the raw laser radiation can also be performed. Particularly advantageously, one or more wavelengths can also be switched on or off to influence the intensity distribution of the segmented focus radiation, i.e., the assigned focus segments can be switched on or off.

[0018] According to a preferred embodiment of the invention, the beam deflection device is designed for wavelength-dependent redirection and / or deflection of the laser radiation, in particular of the first to nth partial laser beams. Depending on the selected embodiment, the beam deflection device particularly advantageously realigns the beam direction of the partial laser radiation or, in advance, divides the laser radiation into partial laser radiation based on wavelength.

[0019] Furthermore, the first to nth partial laser beams advantageously have a different beam direction relative to the propagation direction or the optical axis of the processing optics. As they pass through the beam deflection device, each partial beam is imparted a different angular offset by corresponding optical deflection from the optical axis of the beam deflection device. This assigns a unique beam direction to each controllable or adjustable "radiation channel," with the assigned beam angle being mapped into a unique local position in the processing plane, particularly advantageously by means of the beam-shaping optics and the focusing optics.

[0020] Particularly advantageously, a corresponding number n of first to nth focus segments is generated from a number n of first to nth partial laser radiation, which form the segmented focus radiation in the processing plane, wherein the number n particularly preferably corresponds to the number of wavelengths of the raw laser radiation. Thus, the number of separately controllable or adjustable focus segments corresponds to the number of wavelengths used, which can be doubled, for example, by using an optical fiber with two fiber cores. Particularly preferably, the segmented focus radiation has a linear or rectangular focus geometry.

[0021] In a preferred embodiment, the beam deflection device comprises at least one beam deflection arrangement comprising a plurality of dichroic filter and / or mirror units for reflective beam deflection. The superposition of the partial laser beams is particularly advantageously achieved, for example, by transmitting the partial beams with the shorter wavelength (“short-pass filter”). Alternatively, the partial laser beams can also be transmitted with the longer wavelength (“long-pass filter”).

[0022] In particular, the beam deflection device can comprise a first and a second beam deflection arrangement, each having the same number of dichroic filter and / or mirror units. The first beam deflection arrangement serves for wavelength-dependent filtering of the partial laser radiation from the bundled laser radiation comprising several different wavelengths and for deflecting the filtered partial laser radiation onto an associated dichroic filter and / or mirror unit of the second beam deflection arrangement, via which the beam direction of the filtered partial laser radiation is adjusted.

[0023] According to the invention, the beam-forming optics are formed by at least a first and a second cylindrical lens array. This advantageously implements the principle of non-imaging cylindrical lens homogenization using two crossed cylindrical lens arrays, wherein the cylindrical lens arrays are preferably formed by rod cylindrical lens arrays.

[0024] Furthermore, the focusing optics are advantageously formed by a focusing lens which is arranged directly downstream of the beam forming optics in the beam path.

[0025] Multiple collimation optics can also be provided for separate collimation of the partial laser beams. This advantageously also enables three-dimensional segmentation of the focus beam, namely the setting of different focus positions along the optical axis or propagation axis.

[0026] The invention also relates to processing optics for use in a laser system according to the invention, comprising at least one collimating optic, one beam deflecting device, one beam shaping optic and one focusing optic, wherein the beam deflecting device is particularly advantageously configured to deflect the first to n-th partial laser beams in a predetermined beam direction and the beam shaping and focusing optics are configured to transform the first to n-th partial laser beams into the first to n-th focus segment of the segmented focus radiation, wherein the beam shaping optics is formed by at least a first and second cylindrical lens field, which are arranged one behind the other in the propagation direction and spaced from one another and are aligned orthogonally to one another for two-dimensional beam homogenization.By means of the processing optics according to the invention, a segmented focus radiation with adjustable intensity distribution in a processing plane can be provided particularly advantageously.

[0027] Further developments, advantages, and possible applications of the invention will become apparent from the following description of exemplary embodiments and from the figures. All described and / or illustrated features, individually or in any combination, are fundamentally part of the invention, regardless of their summary in the claims or their reference back to them. The content of the claims is also incorporated into the description. Short description of the drawings

[0028] The invention will be explained in more detail below using exemplary embodiments in conjunction with the drawings. Fig. 1 shows, by way of example, a schematic block diagram of a laser system according to the invention for generating segmented focus radiation; Fig. 2 a schematic plan view of the segmented focus radiation generated in the processing plane; Fig. 3 a schematic side view of a first embodiment of a processing optics according to the invention for generating a segmented focus radiation; Fig. 4 a schematic side view of a second embodiment of a processing optics according to the invention for generating a segmented focus radiation; Fig. 5 a schematic side view of a third embodiment of a processing optics according to the invention for generating a segmented focus radiation; Fig. 6 shows an example of a section through an optical fiber comprising two fiber cores and Fig. 7 shows an example of a perspective arrangement of two crossed cylindrical lens fields. Ways to implement the invention

[0029] Identical reference numerals are used in the figures for identical or equivalently functioning elements of the invention. Furthermore, for the sake of clarity, only those reference numerals are shown in the individual figures that are necessary for the description of the respective figure. The invention is also illustrated in the figures using schematic views. In particular, these schematic representations serve to explain the basic principle of the invention.

[0030] Fig. Figure 1 shows a schematic block diagram of a laser system 1 according to the invention for generating at least one segmented focus beam FS in a processing plane BE. The laser system 1 according to the invention is intended for industrial applications, in particular for tape laying or curing in industrial production processes.

[0031] This is exemplified in Fig. The laser system 1 according to the invention shown in Figure 1 comprises a laser unit 2 for generating a laser radiation LS, preferably a diode laser radiation, and a processing optics 3 for generating a first to n-th partial laser radiation TS1 to TSn, which generates a focus radiation FS in the processing plane BE, which is preferably transmitted to the processing optics 3 via an optical fiber 4.

[0032] The laser unit 2 is formed, for example, by a diode laser unit, preferably a fiber-coupled diode laser unit. This means that the generated laser radiation or diode laser radiation LS is coupled directly into the optical fiber 4 on the input side and fed to the processing optics 3 on the output side. The structure and operation of such diode laser units, in particular fiber-coupled diode laser units, are well known. These typically comprise one or more stacks of diode laser bars, with each diode laser bar comprising a plurality of laser diodes.

[0033] The laser radiation LS preferably propagates along a propagation axis z, which is perpendicular to the processing plane BE and which, with reference to the optical components of the processing optics 3, is also referred to as the “optical axis.” The propagation axis z also forms the z-axis of a Fig. 2 to 5 and 7, comprising an x-axis, y-axis and z-axis. The introduction of the Cartesian coordinate system in the Fig. 2 to 5 and 7 thus serve to describe the processing optics 3 according to the invention with respect to the segmented focus radiation FS generated in the processing plane BE, which, according to the invention, is composed of individual focus segments FS1 to FSn.

[0034] The exemplary in Fig. The segmented focus beam FS shown in Figure 2 comprises a first to n-th rectangular focus segment FS1 to FSn, which lie in the processing plane BE running parallel to the xy plane and, for example, adjoin one another along the y-axis of the Cartesian coordinate system. In the present embodiment, n=4, ie there are four focus segments FS1 to FSn of the Fig. 2.

[0035] Preferably, the z-axis of the coordinate system runs perpendicular to the respective focus segment FS1 to FSN. It is understood that the focus segments FS1 to FSn can be located at almost any position in the xy plane and can also be spaced apart from one another or at least partially overlap without departing from the spirit of the invention. The focus geometry can also deviate from the rectangular shape shown, for example, be linear.

[0036] Furthermore, the laser radiation LS generated by the laser unit 2 has different wavelengths, namely at least a first to nth wavelength w1 to wn. The laser radiation or diode laser radiation LS forms the raw laser radiation, which is subsequently processed accordingly by the processing optics 3 according to the invention in order to generate a segmented focus radiation FS on the application side.

[0037] To generate the laser radiation LS with several different wavelengths w1 to wn, a corresponding number n of laser modules, preferably diode laser modules, can be used in the laser unit 2, for example, which each generate a laser radiation with a wavelength w1 to wn and which are jointly coupled into an optical fiber 4. Alternatively, the laser radiations LS, each having a different wavelength w1 to wn, can also be transmitted separately to the processing optics 3 via a corresponding number n of optical fibers 4.1 to 4.4.

[0038] Via the processing optics 3, the laser radiation LS comprising the first to n-th wavelengths w1 to wn is converted into a first to n-th partial laser radiation TS1 to TSn, wherein each partial laser radiation TS1 to TSn in turn has its own wavelength w1 to wn, for example the first partial laser radiation TS1 has the first wavelength w1, the second partial laser radiation TS2 has the second wavelength w2, the third partial laser radiation TS3 has the third wavelength w3 and the n-th partial laser radiation TSn has the n-th wavelength wn.

[0039] The first to nth partial laser radiation TS1 to TSn is then focused in the processing plane BE by appropriate beam shaping and focusing of the first to nth partial laser radiation TS1 to TSn, thus forming at least one segmented focus radiation FS, wherein the segmented focus radiation FS comprises a first to nth focus segment FS1 to FSn. There is thus a clear relationship between the wavelength w1 to wn of the laser radiation LS coupled into the processing optics 3 and the focus segments FS1 to FSn generated via these in the processing plane BE.

[0040] In an alternative embodiment, instead of a laser radiation LS with several wavelengths w1 to wn, the raw laser beams generated in the laser unit 2, each with a different wavelength w1 to wn, can also be fed to the processing optics 3 via separate optical fibers 4, ie a number of raw laser beams corresponding to the number n of wavelengths w1 to wn is thus fed to the processing optics 3.

[0041] In the present exemplary embodiments, for example, four focus segments FS1 to FSn are generated by means of the processing optics 3 from a laser beam with four different wavelengths w1 to wn or from four laser beams, each with a wavelength w1 to wn. The first to nth wavelengths w1 to wn of the laser beam LS thus form radiation channels that can be individually regulated or controlled via the laser unit 2 depending on the wavelength. The intensity of the respective radiation components of a wavelength w1 to wn can be individually adjusted, and in particular the associated radiation channel can also be switched on or off. This provides temporal control of the radiation channels having different wavelengths w1 to wn.

[0042] The radiation channels formed by the wavelengths w1 to wn are deflected by the processing optics 3 into the first to nth partial laser radiation TS1 to TSn, each with a different beam direction SR1 to SRn, preferably such that the beam direction SR1 to SRn of the first to nth partial laser radiation TS1 to TSn forms an acute angle with the propagation axis z or the optical axis. This wavelength-dependent beam direction is finally transformed by the processing optics 3 into a location-dependent intensity distribution of the segmented focus radiation FS, specifically into the first to nth focus segments FS1 to FSn, wherein the number n of available wavelengths w1 to wn preferably corresponds to the number n of focus segments FS1 to FSn.

[0043] For this purpose, the processing optics 3 according to the invention has at least one collimating optics 5, a beam deflection device 6, a beam shaping optics 7, and a focusing optics 8, which are arranged successively in the propagation direction z of the laser radiation LS. The laser radiation LS, which is transmitted via the optical fiber 4 to the processing optics 3 and diverges depending on the numerical aperture of the laser unit 2, is preferably transferred via an optical connection unit to the collimating optics 5 arranged on the input side of the processing optics 3, via which the beam path of the coupled laser radiation LS is parallelized before it is further deflected or aligned by the beam deflection device 6. The focal length of the collimating optics 5 determines, for example, the diameter of the collimated laser radiation LS.When coupling in several laser beams LS with different wavelengths w1 to wn, a corresponding number of collimation optics 5 must be provided.

[0044] The collimated laser radiation LS is deflected by the beam deflection device 6 into the first to nth partial laser beams TS1 to TSn, each with a different wavelength w1 to wn and a different beam direction SR1 to SRn, and then the first to nth partial laser beams, each with a different wavelength w1 to wn and beam direction SR1 to SRn, are transformed or focused by the beam shaping and focusing optics 7, 8 into the first to nth focus segments FS1 to FSn of the segmented focus radiation FS. In the present exemplary embodiment, the focusing optics 8 preferably generates first to nth focus segments FS1 to FSn with a rectangular focus geometry. In the sense of the invention, a rectangular focus geometry also includes a square focus geometry.

[0045] In Fig. 3 shows an embodiment of a processing optics 3 according to the invention, wherein, for example, the number of wavelengths is limited to n=4. The laser radiation LS transmitted via the optical fiber 4 to the collimation optics 5 thus has a first to fourth wavelength w1 to w4, which is fed to the beam deflection device 6 after collimation, ie the collimated beam bundle thus comprises all four wavelengths w1 to w4.

[0046] According to the invention, the beam deflection device 6 comprises a first and a second beam deflection arrangement 6.1, 6.2, each comprising a plurality of dichroic filter or mirror units 6.11, 6.12, 6.13, 6.14, 6.21, 6.22, 6.23, 6.24, which are each arranged one behind the other in a row along an axis running parallel to the propagation axis or optical axis z, spaced from one another, and are preferably accommodated in a housing 6.3.

[0047] In the present embodiment, the first beam deflection arrangement 6.1 is formed by a first to fourth dichroic filter unit 6.11, 6.12, 6.13, 6.14 and the second radiation deflection arrangement 6.2 is formed by a first to fourth dichroic mirror unit 6.21, 6.22, 6.23, 6.24.

[0048] The first beam deflection arrangement 6.1 is arranged downstream of the collimation optics 5 in the beam path, and the second beam deflection arrangement 6.2 is arranged along a beam path parallel thereto. This means that the dichroic filter or mirror units 6.11, 6.12, 6.13, 6.14, 6.21, 6.22, 6.23, 6.24 are arranged in a matrix, specifically in four consecutive columns and two rows. The first and second beam deflection arrangements 6.1, 6.2 each extend along one of two parallel beam paths.

[0049] In the first and second beam deflection arrangement 6.1, each dichroic filter or mirror unit 6.11, 6.12, 6.13, 6.14, 6.21, 6.22, 6.23, 6.24 is assigned exactly one wavelength w1 to w4, wherein each dichroic filter unit 6.11, 6.12, 6.13, 6.14 of the first beam deflection arrangement 6.1 forms a cooperating filter and mirror pair with exactly one dichroic mirror unit 6.21, 6.22, 6.23, 6.24 of the second beam deflection arrangement 6.2, and wherein the dichroic filter unit 6.11, 6.12, 6.13, 6.14 is used to filter the assigned wavelength w1 to w4 from the laser radiation LS and the dichroic mirror unit 6.21, 6.22, 6.23, 6.24 are arranged for the wavelength-dependent deflection of the beam direction SR1 to SR4 from the optical axis or propagation axis z.

[0050] In the present embodiment according to Fig. 3, the first beam deflection arrangement 6.1 has a first to fourth dichroic filter unit 6.11, 6.12, 6.13, 6.14, wherein the first dichroic filter unit 6.11 is designed to filter the first partial laser radiation TS1 having the first wavelength w1 from the laser radiation LS, the second dichroic filter unit 6.12 is designed to filter the second partial laser radiation TS2 having the second wavelength w2 from the laser radiation LS, the third dichroic filter unit 6.13 is designed to filter the third partial laser radiation TS4 having the third wavelength w3 from the laser radiation LS and the fourth dichroic filter unit 6.14 is designed to filter the fourth partial laser radiation TS4 having the fourth wavelength w4 from the laser radiation LS. By means of the first to fourth dichroic filter units 6.11, 6.12, 6.13, 6.14, a reflective beam deflection of 90° relative to the propagation axis orthe optical axis z, depending on the wavelength w1 to w4. For this purpose, the filter characteristics of the first to fourth dichroic filter units 6.11, 6.12, 6.13, 6.14 are preferably adapted to the sequence of the wavelengths w1 to w4 previously extracted from the collimated beam.

[0051] The second beam deflection arrangement 6.2 has a first to fourth dichroic mirror unit 6.21, 6.22, 6.23, 6.24, wherein the first dichroic mirror unit 6.21 is designed to deflect the first partial laser radiation TS1 received by the first dichroic filter unit 6.11, the second dichroic mirror unit 6.22 is designed to deflect the second partial laser radiation TS2 received by the second dichroic filter unit 6.12, the third dichroic mirror unit 6.23 is designed to deflect the third partial laser radiation TS3 received by the third dichroic filter unit 6.13 and the fourth dichroic mirror unit 6.24 is designed to deflect the fourth partial laser radiation TS4 received by the fourth dichroic filter unit 6.14. According to the invention, each partial laser radiation TS1 to TS4 is individually reflected from the optical axis or by means of the first to fourth mirror units 6.21, 6.22, 6.23, 6.24.Propagation direction z is deflected and thus the first to fourth partial laser radiation TS1 to TS4 is assigned a first to fourth beam direction SR1 to SR4.

[0052] Preferably, the reflective beam deflection of the first to fourth mirror units 6.21, 6.22, 6.23, 6.24 is effected such that each first to fourth partial laser radiation TS1 to TS4, and thus each wavelength w1 to w4, has a uniquely assigned beam direction SR1 to SR4 that deviates from the optical axis z. The first to fourth mirror units 6.21, 6.22, 6.23, 6.24 are thus configured to deflect the received first to fourth partial laser radiation TS1 to TS4 by 90°, less or in addition to an angular offset, which causes the respective beam direction SR1 to SR4 to deviate from the optical axis z of the second beam deflection arrangement 6.2.

[0053] In Fig. 3, the first to fourth partial laser radiations TS1 to TS4 are illustrated by way of example using differently refracted lines. The first partial laser radiation TS1 has a first beam direction SR1, the second partial laser radiation TS2 has a second beam direction SR2, the third partial laser radiation TS3 has a third beam direction SR3, and the fourth partial laser radiation TS4 has a fourth beam direction SR4. The angular offset to the optical axis z set by the first to fourth dichroic mirror units 6.21, 6.22, 6.23, 6.24 is different for each partial laser radiation TS1 to TS4, and is preferably between + / - 0.2° and + / - 10°.

[0054] The propagation axis or optical axis z of the processing optics 3 runs perpendicular to the beam-shaping and focusing optics 7, 8 following the beam deflection device 6, i.e., the first to fourth partial laser beams TS1 to TS4 impinge on the beam-shaping optics 7 at an angle of incidence deviating from the optical axis z, and thus at a "non-perpendicular" angle of incidence. The beam properties in angular space "fixedly assigned" to the partial beams TS1 to TS4 via the beam directions SR1 to SR4 are transformed, after passing through the beam-shaping and focusing optics 7, 8, into an assigned local position of the focus segments FS1 to FS4 in the spatial space of the reference plane BE.

[0055] The local position of the focus segments FS1 to FS4 in the reference plane BE is thus unique and adjustable via the assigned beam direction SR1 to SR4 of the partial beams TS1 to TS4. In the present embodiment, the positions of four focus segments FS1 to FS4 in the processing plane BE can be controlled and regulated separately from one another via the four wavelengths w1 to w4 via a corresponding configuration of the second beam deflection arrangement 6.2 of the beam deflection device 6.

[0056] In a preferred embodiment, the beam-shaping optics 7 are formed by first and second cylindrical lens arrays 7.1, 7.2, each comprising a plurality of cylindrical lenses or cylindrical lens sections. The first and second cylindrical lens arrays 7.1, 7.2 are each formed by a plurality of cylindrical lenses or cylindrical lens sections arranged parallel to one another, each arranged in a plane running parallel to the processing plane BE and spaced apart from one another. Fig. 7 shows an example of a schematic view of a correspondingly designed beam-shaping optics 7.

[0057] The first and second cylindrical lens fields 7.1, 7.2 are arranged one behind the other along the radiation path or the propagation axis z, respectively, and spaced apart from one another, specifically crossed. The longitudinal axes of the cylindrical lenses of the first cylindrical lens field 7.1 each run parallel to the x-axis of the Cartesian coordinate system, and the longitudinal axes of the cylindrical lenses of the second cylindrical lens field 7.2 each run parallel to its y-axis. The longitudinal extent and / or the number of cylindrical lens sections of the first and second cylindrical lens fields 7.1, 7.2 are configured such that a preferably rectangular or square field is created. The first and second cylindrical lens fields 7.1, 7.2 are preferably adapted to one another such that an at least approximately congruent imaging area results.

[0058] The intersecting first and second cylindrical lens fields 7.1, 7.2 are preferably implemented as rod cylindrical lens fields. The radiation-shaping optics 7 thus has a beam-shaping concept that corresponds to the principle of non-imaging cylindrical lens homogenization. The first and second cylindrical lens fields 7.1, 7.2 split the first to fourth partial laser radiation TS1 and TS4 and multiply images of the laser light source. The first to fourth partial laser radiation TS1 to TS4 are superimposed in the focal plane of the focusing optics 8 adjoining the beam-shaping optics 7, creating a mixing effect that results in homogeneous illumination along the optically effective axis of the first and second cylindrical lens fields 7.1, 7.2. Due to the orthogonal alignment of the first and second cylindrical lens fields 7.1, 7.2 to one another, a two-dimensional beam homogenization results.

[0059] The focusing optics 8 are preferably formed by a focusing lens. The dimensions of the images created by the beam-shaping optics 7 can be adjusted via the distance ("pitch") between the cylindrical lenses, the focal length of the cylindrical lenses, and the focal length of the downstream focusing optics 8.

[0060] In the present embodiment according to Fig. 3 creates four focus segments FS1 to FS4, which are Fig. 3 are shown rotated 90° counterclockwise around the y-axis, ie the focus segments FS1 to FS4, each with a rectangular focus geometry, extend in the processing plane BE.

[0061] The number n of generated focus segments FS1 to FSn per processing optics 3 can be increased, for example, by using several processing optics 3, so that a segmentation comprising nxm focus segments is possible.

[0062] In Fig. 4 shows a further embodiment of a processing optics 3 according to the invention, wherein, unlike the embodiment according to Fig. 3 the laser radiations LS, LS' are transmitted twice via the optical fiber 4 to the processing optics 3. The optical fiber 4 comprises two fiber cores 4a, 4b as shown by way of example in the cross-sectional view according to Fig. 6. The two laser beams LS, LS' each have a first to fourth wavelength w1 to w4. This results in a doubling of the controllable or adjustable radiation channels or the associated focus segments FS1 to FS4, FS1' to FS4'. The higher number of segments enables a finer distribution of the intensity in the processing plane BE.

[0063] The structure and functioning of the beam deflection device 6, the beam shaping optics 7 and the focusing optics 8 essentially correspond to the embodiment according to Fig. 3.

[0064] The coupling in turn takes place via the at least one collimation optics 5, to which the laser radiations LS, LS' emerging from the optical fiber 4 are fed, namely parallel to the optical axis z. In the present exemplary embodiment, a laser radiation LS, LS' with a first to fourth wavelength w1 to wn thus emerges from each fiber core 4a, 4b. Preferably, the distance of the fiber cores 4a, 4b of the optical fiber 4 from the optical axis z of the collimation optics 5 is approximately identical, so that for both laser radiations LS, LS' an angular deviation from the optical axis z of the collimation optics ("off-axis collimation") of identical magnitude arises, but with opposite signs.For each of the four wavelengths w1 to wn of the laser radiations LS, LS', two radiation fields are then generated, each comprising a first to fourth partial laser radiation TS1, TS2, TS3, TS4, TS1', TS2', TS3', TS4' with an associated angular deviation, which depends on the distance between the fiber cores 4a, 4b and the focal length of the collimation optics 4. This fixed property in the angular space is transformed, after passing through the beam-shaping optics 7 and the focusing optics 8, into a correspondingly assigned and separately controllable local position in the processing plane BE.

[0065] Via the off-axis collimation of each of the four wavelengths w1 to wn of the laser radiations LS, LS', a first to fourth partial laser radiation TS1 to TS4, TS1' to TS4', i.e. a total of eight partial laser radiations TS1 to TS4, TS1' to TS4', are generated therefrom, wherein the first to fourth partial laser radiation TS1 to TS4, TS1' to TS4' of a laser radiation LS, LS' each have an almost identical angular deviation, i.e. the beam directions SR1 to SR4, SR1' to SR4' of the first to fourth partial laser radiation TS1 to TS4, TS1' to TS4' are analogous to the embodiment according to Fig. 3 redirected accordingly.

[0066] The angular components of the individual wavelengths w1 to w4 are manipulated by the previously described wavelength separation with subsequent reflective re-superposition in the beam deflection device 6 in such a way that after passing through the beam shaping optics 7 and the focusing optics 8 in the processing plane BE, eight spatially separated focus segments FS1 to FS4, FS1' to FS4' are created.

[0067] The reflective beam deflection by the beam deflection device 6 is carried out in particular in such a way that each wavelength w1 to w4 is assigned two first to fourth partial laser radiations TS1 to TS4, TS1' to TS4' deflected from the optical axis z, which partial laser radiations have an additional common angular deviation which differs from the respective other partial laser radiations TS1 to TS4, TS1' to TS4'.

[0068] In the embodiment according to Fig. 4, eight focus segments FS1 to FS4, FS1' to FS4' of the segmented focus radiation FS are created, which are Fig. 4 are shown rotated 90° counterclockwise around the y-axis. The eight focus segments FS1 to FS4, FS1' to FS4' each have a rectangular focus geometry and extend in the processing plane BE.

[0069] In Fig. Figure 5 shows a further, alternative embodiment of the processing optics 3 according to the invention. Here, the first to fourth partial laser radiation TS1 to TS4 is supplied separately to the processing optics 3 via a first to fourth optical fiber 4.1 to 4.4.

[0070] Accordingly, each partial laser beam TS1 to TS4 is coupled into the beam deflection device 6 via a collimation optics 5.1 to 5.4 arranged on the input side, so that the first beam deflection arrangement 6.1 can be omitted. The structure and function of the beam shaping optics 7 and the focusing optics 8 are unchanged compared to the embodiment according to Fig. 3 and Fig. 4.

[0071] The first to fourth partial laser radiations TS1 to TS4, each having a different wavelength w1 to w4, are coupled into the beam deflection device 6, which also has a housing 6.3, via the four separate optical fibers 4.1 to 4.4, spaced apart along the y-axis. The beam deflection device 6 also has a housing 6.3. The collimated first to fourth partial laser radiations TS1 to TS4 are coupled in such a way that the first partial laser radiation TS1 is transmitted to the first mirror unit 6.21 of the second beam deflection arrangement 6.2, the second partial laser radiation TS2 to the second mirror unit 6.22, the third partial laser radiation TS3 to the third mirror unit 6.23, and the fourth partial laser radiation TS4 to the fourth mirror unit 6.24.

[0072] Analogous to the design variant according to the Fig. 3, the first to fourth partial laser radiation TS1 to TS4 are deflected to the optical axis of the beam deflection device 6 by means of the first to fourth mirror units 6.21, 6.22, 6.23, 6.24 in such a way that each of the first to fourth partial laser radiation TS1 to TS4 and thus each wavelength w1 to w4 has a uniquely assigned beam direction SR1 to SR4. The beam direction SR1 to SR4 again deviates from the optical axis of the second beam deflection arrangement 6.2, wherein the optical axis of the beam deflection device 6 is different from the embodiment variant according to Fig. 3 extends along the y-axis. The correspondingly deflected partial laser radiation TS1 to TS4 is deflected via a further deflection device 9, which is arranged between the beam deflection device 6 and the beam-shaping optics 7, into the propagation axis z or optical axis of the beam-shaping optics 7 and the subsequent focusing optics 8, and is accordingly imaged into the processing plane BE.

[0073] The deflection device 9 can be formed, for example, by a broadband deflection mirror. Analogous to Fig. 3, the desired four focus segments FS1 to FS4 of the segmented focus radiation FS are thus generated in the processing plane BE.

[0074] In the version according to Fig. 5 is therefore analogous to Fig. 3 a segmented focus radiation FS with four focus segments FS1 to FS4 is generated, which in Fig. 5 are shown rotated 90° counterclockwise around the y-axis. The four focus segments FS1 to FS4 each have a rectangular focus geometry and extend in the processing plane BE.

[0075] The adjacent arrangement of the focus segments FS1 to FS4 of the segmented focus radiation FS in the embodiments according to Fig.3 to 5 are chosen as examples. It is understood that the focus segments FS1 to FS4 can partially or completely overlap and / or be arranged at a distance from one another without thereby departing from the inventive concept.

[0076] The invention has been described above using exemplary embodiments. It is understood that numerous changes and modifications are possible without departing from the spirit of the invention. List of reference symbols 1 laser system 2 laser units 3 Processing optics 4 optical fibers 4.1 to 4.4 first to fourth optical fiber 4a Fiber core 4b Fiber core 5 Collimation optics 5.1 to 5.4 first to fourth collimation optics 6 Beam deflection device 6.11 first dichroic filter unit 6.12 second dichroic filter unit 6.13 third dichroic filter unit 6.14 fourth dichroic filter unit 6.21 first dichroic mirror unit 6.22 second dichroic mirror unit 6.23 third dichroic mirror unit 6.24 fourth dichroic mirror unit 6.3 Housing 7 Beam shaping optics 7.1 first cylindrical lens field 7.2 second cylindrical lens field 8 Focusing optics or focusing lens 9 additional deflection device BE processing level FS segmented focus radiation FS1 to FSn first to nth focus segment FS1' to FS4' first to fourth focus segment LS, LS' laser radiation n Number of wavelengths / segments SR1 to SRn first to n-th beam direction SR1' to SR4' first to fourth beam direction TS1 - TSn first to n-th partial laser radiation TS1' - TS4' first to fourth partial laser radiation w1 - wn first to n-th wavelength x x-axis y y-axis z z-axis or propagation direction

Claims

[1] Laser system (1) for generating at least one segmented focus radiation (FS) consisting of a first to n-th focus segment (FS1 to FSn) comprising at least one preferably fiber-coupled laser unit (2) for generating a laser radiation (LS) with different wavelengths (w1 to wn) and a processing optics (3) connected to it, wherein the processing optics (3) has at least one collimating optics (5), a beam deflection device (6), a beam shaping optics (7) and a focusing optics (8) which are arranged successively in the propagation direction (z) of the laser radiation (LS), wherein the laser radiation (LS) generated by the laser unit (2) is deflected by means of the beam deflection device (6) into first to n-th partial laser beams (TS1 to TSn) each having a different wavelength (w1 to wn) and beam direction (SR1 to SRn), and wherein by means of the beam shaping and focusing optics (7,8) the first to n-th partial laser beams (TS1 to TSn) are transformed into the first to n-th focus segments (FS1 to FSn) of the segmented focus radiation (FS), , characterized by that the beam forming optics (7) is formed by at least a first and a second cylindrical lens field (2.1, 2.2) which are arranged one behind the other and spaced from one another in the propagation direction (z) and are aligned orthogonally to one another for two-dimensional beam homogenization. [2] Laser system (1) according to claim 1, characterized by that the local position of the first to n-th focus segments (FS1 to FSn) in the processing plane (BE) and / or the intensity of the first to n-th focus segments (FS1 to FSn) in the processing plane (BE) can be adjusted independently and / or separately from one another. [3] Laser system (1) according to claim 1 or 2, characterized by that the segmented focus radiation (FS) has a spatially and / or temporally variable intensity distribution. [4] Laser system (1) according to one of claims 1 to 3, characterized by that the beam deflection device (6) is designed for wavelength-dependent redirection and / or deflection of the laser radiation (LS), in particular the first to n-th partial laser beams (TS1 to TSn). [5] Laser system (1) according to one of the preceding claims, characterized by that the first to n-th partial laser beams (TS1 to TSn) have a different beam direction (SR1 to SRN) relative to the propagation direction or the optical axis (z) of the processing optics (3). [6] Laser system (1) according to one of the preceding claims, characterized by that from a number (n) of first to n-th partial laser radiation (TS1 to TSn) a corresponding number (n) of first to n-th focus segments (FS1 to FSn) is generated, which form the segmented focus radiation (FS) in the processing plane (BE). [7] Laser system (1) according to one of the preceding claims, characterized bythat the segmented focus radiation (FS) has a linear or rectangular focus geometry. [8] Laser system (1) according to one of the preceding claims, characterized by that the beam deflection device (6) has at least one beam deflection arrangement (6.1, 6.2) comprising a plurality of dichroic filter and / or mirror units (6.11 to 6.14, 6.21 to 6.24) for reflective beam deflection. [9] Laser system (1) according to claim 8, characterized by that the beam deflection device (6) has at least a first and a second beam deflection arrangement (6.1, 6.2), each having the same number (n) of dichroic filter and / or mirror units (6.11 to 6.14, 6.21 to 6.24). [10] Laser system (1) according to one of the preceding claims, characterized by that the focusing optics (8) is formed by a focusing lens. [11] Laser system (1) according to one of the preceding claims, characterized bythat several collimation optics (5.1 to 5.4) are provided for the separate collimation of the partial laser beams (TS1 to TSn). [12] Processing optics (3) for use in a laser system (1) according to one of the preceding claims, comprising at least one collimating optics (5), a beam deflection device (6), a beam shaping optics (8) and a focusing optics (8), wherein the beam deflection device (6) is configured to deflect the first to n-th partial laser beams (TS1 to TSn) in a predetermined beam direction (SR1 to SRn) and the beam shaping and focusing optics (7, 8) are configured to transform the first to n-th partial laser beams (TS1 to TSn) into the first to n-th focus segments (FS1 to FSn) of the segmented focus radiation (FS), characterized bythat the beam forming optics (7) is formed by at least a first and a second cylindrical lens field (2.1, 2.2) which are arranged one behind the other and spaced from one another in the propagation direction (z) and are aligned orthogonally to one another for two-dimensional beam homogenization. [13] Processing optics (3) according to claim 12, characterized by that the beam deflection device (6) is designed for wavelength-dependent redirection and / or deflection of the laser radiation (LS), in particular the first to n-th partial laser beams (TS1 to TSn). [14] Processing optics (3) according to claim 12 or 13, characterized by that the beam deflection device (6) has at least one beam deflection arrangement (6.1, 6.2) comprising a plurality of dichroic filter and / or mirror units (6.11 to 6.14, 6.21 to 6.24) for reflective beam deflection. [15] Processing optics (3) according to claim 14, characterized bythat the beam deflection device (6) has at least a first and a second beam deflection arrangement (6.1, 6.2), each having the same number (n) of dichroic filter and / or mirror units (6.11 to 6.14, 6.21 to 6.24). [16] Processing optics (3) according to one of claims 12 to 15, characterized by that the focusing optics (8) is formed by a focusing lens. [17] Processing optics (3) according to one of claims 12 to 16, characterized by that several collimation optics (5.1 to 5.4) for the separate collimation of the partial laser beams (TS1 to TSn) are connected upstream of the beam deflection device (6). [18] Processing optics (3) according to one of claims 12 to 17, characterized by that a further deflection device (9) for deflecting the first to n-th partial laser beams (TS1 to TSn) with different beam directions (SR1 to SRn) is arranged between the beam deflection device (6) and the beam forming optics (7).

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