DE19840927A1 - Laser radiation source of high power density and high energy for material processing - Google Patents

Abstract

Laser radiation source of high power density and high energy, which can preferably be used for material processing. An optical unit (8) is provided for shaping the laser beam on a processing surface (81). Several directly modulatable diode-pumped fiber lasers (fiber lasers) (2) are used, the outputs (13) of which are arranged in a bundle and the rays (13) emerging from the lasers (2) are combined and bundled in this way by means of the optical unit (8) be that the rays hit a point on a processing surface (81).

Description

The invention relates to a laser radiation source of high power density and high Energy, preferably for material processing, the multiple diode-pumped Has fiber laser over the end pieces with an optical unit are connected. The optical unit contains means for shaping the laser beam, a modulation device and a transmission unit for transmitting the Laser beams on a processing area. Furthermore, means for Make the unwanted laser radiation harmless on the Machining area should not produce a machining effect, and a Arrangement for removing the removed from the processing surface Material provided.

When processing materials with bundled laser beams, there are Use cases, for example in printing technology when creating Printing forms for gravure printing, in which structures, namely so-called Cups that need to be created in the surface of a copper cylinder high demands on the bundled energy beam with regard to its Beam geometry and the focusability of the beam. At the same time a large steel output is required. They are from the specialist literature and from the Patent literature arrangements known to attempt an individual Bundle the laser beam and thus remove material. With one It is a laser arrangement consisting of a single solid-state laser possible to process gravure cylinders with a zinc surface, but you want to take advantage of the copper surface and stay with copper cylinders and Engrave them with a laser, it is essential to penetrate them Surface of the copper required high power density and the to  Melting the copper requires high energy while being precise controllable beam geometry to apply. So far this is with Solid-state lasers failed.

The object of the present invention is therefore a laser radiation source to create extremely high power density and very high energy. The disadvantages the known arrangements and methods are basically to be avoided become. In addition, it should be possible to use both the beam shape, which means the flexibility, Precision and beam positioning affects as well as the beam power itself precisely control significantly higher laser powers.

This object is achieved by the laser radiation source according to the invention Claim 1 solved. Advantageous developments of the invention are in the Subclaims 2 to 101 described. In parallel, simultaneously with German patent application filed in the present application "Process and arrangement for material processing by means of laser beams", characters the applicant 98/1035, such a laser radiation source is described, which basically the disadvantages of the known arrangements and methods avoids. It is also possible to change the beam shape, which means flexibility, Precision and beam positioning affects as well as the beam power itself precisely control significantly higher laser powers.

The laser radiation source consists of several diode-pumped fiber lasers, also called fiber lasers, whose output beams by means of the optical Unit at the processing site next to each other and / or one above the other or in one Point or bundle hit and thus the creation of a shape and size selectively variable machining spots even with very high laser powers and enable extremely high power densities. According to the Invention as a continuous wave laser or as a Q-switched laser, also Q-switch Called laser, be carried out, they advantageously internal or external be modulated and / or have an additional modulator. Q switch Lasers have the advantage that they emit short, high power pulses, which temporarily leads to a high power density. It is going through in pulsed mode  the short interruptions in the machining process are advantageous Allows removal of the molten and vaporized material. One can instead of switching the quality also by means of internal or external modulation generate pulsed operation. The processing spot can be targeted in shape and Size can be changed by different numbers of the intended lasers can be switched on to shape the machining spot. Here is particularly advantageous that the depth of the excavated well regardless of their shape and size can be determined by the laser energy. Farther can do any by controlling the energy of each laser Beam profile within the processing spot and thus also within the Cups are generated.

When processing materials, it is desirable to use laser energy Bring optical fibers as close as possible to the processing surface. On Advantage of the present invention over the known Laser radiation sources consist in that the coupling of the radiation from a solid-state laser can be omitted in an optical fiber, but the output of the Fiber lasers, which is already the fiber, provides diffraction limited radiation, which are focused according to the invention to a spot diameter of less than 10 μm can, resulting in an extremely high power density with the greatest possible depth of field is achieved.

In a conventional arrangement with solid-state lasers, the size of the Machining spots in the range of approximately 100 µm. So it results in the present invention an approximately 100 times improved power density and an approximately 100 times better design option for the Machining spots.

Another advantage of the invention is that the efficiency of such Arrangement with fiber lasers is much higher than the efficiency of Solid-state lasers, because for fiber lasers, absorption efficiencies of over 60% achieved, which is only the case with conventional diode-pumped solid-state lasers  about half and still with lamp-pumped solid-state lasers are lower.

Furthermore, with a multiple arrangement of lasers, there is the advantage that the failure of a laser is less critical than with a single-channel arrangement. In the single-channel arrangement, one laser falls during the engraving of one Printing cylinder, the entire printing cylinder is unusable. But falls with a multiple array a laser, then you can see the performance of the Increase the remaining laser slightly to compensate for the failure. To at the end of the engraving, the failed laser can then be replaced.

The laser radiation source according to the invention can advantageously also for everyone other types of material processing or material transfer used be where there is high power density, high energy and great Precision or high optical resolution is important. In addition to the engraving by Gravure forms made of copper can use other materials such as B. all metals, Ceramics, glass, semiconductor materials, rubber or plastics can be processed and / or materials detached from specially prepared carrier materials and on transfer other materials with high speed and high precision become. In addition to uncoated masks can also be coated Gravure cylinders, printing plates or printing cylinders as well as all types of Printing forms at high speed and with high resolution for offset, Printing, screen printing, flexo printing and all other printing processes to be edited. For example, those for printing can also be very high Offset printing plates used offset plates with metal coating (Bimetallic plates) and similar items are illustrated in an environmentally friendly way could only be produced by etching.

Furthermore, materials can be processed that are magnetizable Surface included by the through a bias process Large areas of magnetized material by brief heating selected machining points on temperatures above the Curie point lie, demagnetized by means of the laser radiation source according to the invention  become. For applications in printing technology, this can be done in this way imaged material in combination with a suitable toner as Serve as a template.

However, the application of the laser radiation source according to the invention is not limited to Applications in the printing industry are limited, but they can be anywhere be used where it matters, with lasers at high resolution and abrasion or in high speed by energy radiation to change its properties.

A significant advantage of the laser radiation source according to the invention is that it has a small volume and via a flexible connection, namely the Laser fibers or connected fibers between the pump source and the Exit of the radiation at the processing location and thereby all conceivable Operating positions. That is why there are also for the arrangement of the Machining area no limits, it can be arranged as desired.

Another advantage of the invention is that the rays of the single laser with defined values in beam diameter, beam divergence, Centering and angular direction in the end pieces precisely and permanently can be grasped to a production and service-oriented arrangement receive and direct the laser radiation to the processing surface. In of the parallel running, submitted simultaneously with the present application German patent application "end piece for optical fibers", sign of Applicant 98/1037, and in parallel, simultaneously with the present Application submitted German utility model application "final piece for optical fibers ", trademark of applicant 98/1037 GM, are different Exemplary embodiments of such end pieces are described. The rays can according to the invention depending on the application z. B. as parallel Laser beams are decoupled, diverge or z. B. in a certain Distance from the exit point. Through these end pieces the position of the respective fiber from which the laser energy emerges in the End piece (terminator) exactly fixed and the position of the emerging  Beam precisely adjusted. With this exact adjustment and one according the invention corresponding to the spatially small design of the end pieces due to a special shape, it is also particularly easy to connect to one another can be lined up, it becomes possible to beam multiple fiber lasers summarize and bundle so that the task is solved and at the same time an economical production as well as an economical one Maintenance of the laser radiation source is made possible.

The invention is explained in more detail below with reference to FIGS. 1 to 14a. Show it:

Fig. 1 is a schematic representation of the laser radiation source,

Fig. 2 is a schematic representation of a fiber laser (prior art)

FIG. 2a is a condensed representation of the fiber of the fiber laser (prior art),

Fig. 3 is an illustration of the optical unit, in a multi-part recording at a laser radiation source having an array of fiber lasers

Fig. 3a shows a perspective view to Fig. 3,

FIG. 3b is an enlargement possibility of Fig. 3,

FIG. 3c another extension possibility to Fig. 3,

Fig. 3d is an example of a multiple socket for a plurality of terminators,

Fig. 3e, a lens, which is flowed around by a coolant,

Fig. 3f shows a section through a holder for the objective lens,

Fig. 4 shows a variant of Fig. 3,

Fig. 5 shows a further variant of FIG. 3 and 4,

Fig. 6 shows an example of an end piece with a square cross-section,

FIG. 6a shows a cross section through the end piece of FIG. 6,

Fig. 7 shows an example of an end piece with a rectangular cross section and a trapezoidal plan view,

Fig. 7a shows a longitudinal section through the end piece of FIG. 7,

Fig. 7b shows a cross section through the end piece of FIG. 7,

Fig. 8 shows an arrangement with an electro-optical modulator,

Fig. 9 is a plan view of a four-channel acousto-optical modulator,

Fig. 9a shows a section through the modulator of FIG. 9,

Fig. 10 shows a basic light path for a top view of FIG. 3,

Fig. 11 is a principal beam path for a plan view of Fig. 4,

Fig. 12 shows a basic light path for a top view of FIG. 5,

Fig. 13 shows a beam path for end pieces which are arranged at an angle to each other,

FIG. 14 shows a variant of FIG. 13, which contains a multi-channel acousto-optical modulator, and

Fig. 14a a detail of Fig. 14.

In Fig. 1 is a laser radiation source 1 is shown, the running of a plurality of the invention preferably as modules, diode-pumped fiber lasers and fiber lasers S (2), which are acted upon by a preferably modular supply 32 with electrical energy, some of which in the laser radiation is implemented. Furthermore, a controller 33 is provided, via which the radiation is modulated and which ensures the interaction of the laser radiation source with its periphery. The output beams of the lasers enter the optical unit 8 at the radiation input 9 and exit the optical unit at the radiation output 10 . The laser radiation is shaped by the optical unit 8 into a processing spot 24 on a processing surface 81 .

In Figs. 2 and 2a of the basic structure of a fiber laser array 2, also called fiber laser is shown. In Fig. 2, the energy of a pump source such. B. a laser diode, here called pump source 2 , formed via a coupling optics 3 to a suitable pump leak 4 and coupled into the laser fiber 5 . Such pump sources are e.g. B. in the parallel German patent application with the file number P 196 03 704 described. Typical pump cross sections of the laser fibers are between 100 µm and 600 µm with a numerical aperture of around 0.4. The laser fiber 5 is provided on the coupling-in side 6 with a coupling-in mirror 7 which allows the pump radiation to pass through unhindered, but which has a 100% reflection for the laser radiation. The coupling mirror 7 can be fastened to the fiber end with a suitable holder or by gluing, but it can also be realized by direct vapor deposition of a suitable layer, such as is used in coupling mirrors for lasers, on the fiber end. On the coupling-out side 11 of the laser fiber 5 there is a coupling-out mirror 12 which is partially transparent to the laser radiation and through which the laser radiation 13 is coupled out. The decoupling mirror for the pump radiation advantageously has a 100% reflection. As a result, the remaining pump radiation is reflected back into the optical fiber, which is advantageous since the pump energy is better utilized and also does not interfere with the use of the laser radiation. The coupling-out mirror, like the coupling-in mirror, can also be produced by vapor deposition.

The coupling process of the pump radiation into the pump cross section 14 of the laser fiber 5 is shown in more detail in FIG. 2a. The energy in the pump spot 4 excites the laser radiation in the core 15 of the laser fiber 5 on its way through the fiber. The pump core 16 is surrounded by a jacket 17 . The approximately 5 µm to 10 µm thick core of the laser fiber is mainly doped with rare earths. As a result of the deliberately produced, very small fiber core diameter, the fiber laser delivers a practically diffraction-limited laser radiation 13 at the outlet. Passive fibers 28 can also be coupled to the active output of fiber lasers.

In Fig. 3 is a section through an application example of a multi-part receptacle for adaptation of the optical unit of a laser radiation source having sixteen fiber lasers which are coupled via terminators 26, and two multi-channel acousto-optical modulators 34 shown. The receptacle contains sockets 29 ( Fig. 3a) with fitting surfaces for the fit or fits of the end pieces 26 , means for merging the individual laser beams, the modulation unit, the transmission unit for transmitting the laser radiation, which is to produce a machining effect, onto the machining surface 81 and one Arrangement for rendering the laser radiation harmless, which should not have any processing effect. The arrangement for removing the material removed from the processing surface can be arranged on the multi-part receptacle, but can also be attached in a different way near the processing surface.

Fig. 3a is a perspective view to FIG. 3.

FIG. 4 shows a variant of FIG. 3, in which the beams of the individual fiber lasers do not run parallel as in FIG. 3, but at an angle to one another, which is not apparent from the sectional drawing in FIG. 3 and therefore in Figs. 10 to 14 is explained in detail.

FIG. 5 shows a variant of FIG. 4 which, as a result of a differently designed transmission unit, enables an advantageous, considerably more compact design.

Referring first to FIG. 3 with the aid of Fig. 3a explained in detail. These explanations also apply analogously to FIGS. 4 and 5.

In a housing 35 there are 4 fiber lasers F _HD1 to F _HD4 , F _VD1 to F _VD4 , F _HR1 to F _HR4 , F _VR1 to F _VR4 via F _HD1 to F _HD4 , F _VD1 to F at the radiation entrance 9 ( FIG. 1) _VD4 , F _HR1 to F _HR4 , F _VR1 to F _VR4 are arranged next to one another in one plane via the end pieces 26 by means of the sockets 29 in four tracks each with a radiation packet. The embodiment of the end pieces 26 used in FIG. 3 is described in more detail in FIGS. 6, 6a, 7, 7a and 7b. The end pieces should preferably be inserted gas-tight in the housing 35 , for which purpose seals 36 ( FIG. 3a) can be used. Instead of the end pieces shown, differently shaped end pieces can also be used if corresponding sockets 29 are provided in the housing 35 . The fiber lasers F _HD1 to F _HD4 or F _VR1 to F _VR4 should, for example, have a different wavelength than the fiber lasers F _VD1 to F _VD4 or F _HR1 to F _HR4 . For example, F _HD1 to F _HD4 and F _VR1 to F _{VR4 should have} a wavelength of 1100 nm, while F _VD1 to F _VD4 and F _HR1 to F _{HR4 should have} a wavelength of 1060 nm, which is due to a corresponding doping of the laser-active core material the laser fiber 5 can be reached. However, all fiber lasers can also have different wavelengths if they are put together accordingly.

The wavelength packets of the fiber lasers F _HD1 to F _HD4 with those of the fiber lasers F _VD1 to F _VD4 and the radiation packets of the fiber lasers F _VR1 to F _VR4 with those of the fiber lasers F _HR1 to F _HR4 each become a radiation packet via wavelength-dependent mirrors 37 F _D1 to F _D4 and F _R1 to F _R4 ( Fig. 3a) combined. There are also other options for influencing the wavelength of the fiber lasers, for example in the area of the laser fibers between coupling mirror 7 and coupling mirror 12, wavelength-selecting elements such as Brewster plates, diffraction gratings or narrow-band filters can be introduced. It is also possible to provide at least one of the two laser mirrors 7 or 12 with a mirror layer which is sufficiently highly reflective only for the desired wavelength. However, the execution of the beam merging is not limited to the use of fiber lasers of different wavelengths according to the invention. In addition to fiber lasers that have no preferred direction in the polarization of the emitted laser radiation, fiber lasers that emit polarized laser radiation can also be used. If one replaces the wavelength-dependent mirror with one that is so polarization-dependent that it transmits one direction of polarization while reflecting the other direction of polarization, only two differently polarized laser types have to be used in order to unite both by means of the polarization-dependent mirror. In this case, the use of the end piece 26 according to FIGS. 6 and 6a with a square cross section is particularly suitable, since by turning the end piece through 90 ° before assembly in the housing 35 , one or the other polarization direction is generated with the same fiber laser can.

A particular advantage of combining several lasers into a single spot, namely for each of the individual processing points B ₁ to B _n (for example B ₁ to B ₄ in FIGS. 10 to 12) is the achievement of a higher power density for a given spot size on the Processing area 81 .

By omitting fiber lasers or traces, the acquisition costs for such an arrangement can be reduced as required and fiber lasers can be retrofitted later as required. For example, you can start with a fiber laser and a track. The missing end pieces of the fiber lasers not used are replaced by identical end pieces, which, however, contain no through opening and no laser fibers and are only used for closing, in order to close the housing 35 as if it were equipped with all end pieces.

The number of levels in which the end pieces are arranged is not limited to the one level described and the number of tracks is not limited to the 4 tracks described. In Fig. 3b z. B. specified an arrangement with 3 levels and n tracks.

The respective radiation packets of the fiber lasers are modulated via a four-channel acousto-optical modulator 34 , the mode of operation and embodiment of which is explained in more detail in FIGS . 9 and 9a. Through the acousto-optical modulator 34 , which is a deflector in principle, the undesired energy is deflected from the original beam direction 10 into the beam direction I ₁ in the illustrated case ( FIG. 3a), so that it is simply intercepted later in the beam path and is harmless can be made. The modulation can preferably be carried out digitally, ie a distinction is only made in the individual modulator channels between two states, namely "ON" and "OFF", which is particularly easy to control; however, it can also be done analogously by setting the laser power to any value in each modulator channel. The modulation is not limited to the fact that the energy from the beam direction 10 is used for the processing and the energy from the direction I _{1 is made} harmless. In the parallel German patent application "Process and arrangement for material processing by means of laser beams", filed by the applicant 98/1035 and filed simultaneously with the present application, examples are given in which the deflected beam direction I _{1 is used} for processing and the energy from the direction I _{0 is} rendered harmless.

The multi-channel acousto-optical modulator 34 is preferably fastened on a cylindrical modulator housing 41 , which is rotatably mounted in an opening 48 in the housing 35 . After adjusting the modulator housing to the required Bragg angle α _B , the modulator housing is fixed by means of a connection 42 . A seal 43 ensures that each modulator housing is gas-tight to the housing 35 . A specially prepared circuit board 171 protrudes from the modulator housing 41 into the inner space 44 of the housing 35 , via which the electrical connections to the piezoelectric transducers 45 are made. The preferred embodiment of the modulators is described in more detail in FIGS. 9 and 9a.

After passing through the acousto-optical modulators, the radiation packets F _D1 to F _D4 and F _R1 to F _{R4 are} guided to a strip mirror 46 which is alternately transparent and mirrored in strips at intervals. The radiation packet F _D1 to F _D4 is arranged with respect to the strip mirror 46 in such a way that it can pass through the strip mirror unhindered. The laser beams of the radiation packet F _R1 to F _R4 are offset from the radiation packet F _D1 to F _D4 by half a track spacing and hit the striped mirrored strips of the strip mirror. As a result, they are deflected in their direction and are now in one plane with the laser beam bundles F _D1 to F _D4 . This now results in an eight-track arrangement in which two lasers of different wavelengths are also superimposed in each track, so that a total of 16 lasers have been brought together and come into effect. Above this level I ₀ are the beams I ₁ diffracted in the acousto-optical modulator 34 . With another adjustment of the acousto-optical modulator 34 , the deflected beams can also lie below the plane of I ₀ , as is shown in FIGS. 4 and 5.

A significant advantage of the arrangement according to the invention is that the axis of symmetry of the beam _packets F _HD1 to F _HD4 and F _D1 to F _D4 lie on the axis of the housing 35 which is defined by the bore 47 and the beam axes of the associated beam packets are each parallel or are perpendicular to this axis, which allows simple and precise manufacture. However, it is also possible to arrange the beam packets asymmetrically and at different angles.

It is also possible to correct small differences in the position of the radiation packets by adjusting the wavelength-dependent mirrors 37 and the strip mirror 46 . It is possible to readjust the position and angular assignment of the end pieces after assembly, but this is not shown in the figures.

It is within the scope of the invention that the number of tracks is reduced, but also can be further increased, e.g. B. can be by stringing eight each instead of four end pieces, which are connected with fiber lasers, into one Radiation packet a doubling of the number of tracks can be made. To two 8-channel acousto-optical modulators would have to be used. There are acousto-optical modulators with 128 separate channels on one crystal available.

It is also possible according to the invention, to increase the power per track, to arrange the fiber lasers in different planes and to superimpose their power on the processing surface, which is shown in FIG. 3b.

Directly modulable fiber lasers can also be used. In this case there is no need for the acousto-optical modulators and there is a special one easy construction.

Operation with multiple tracks of lasers and multiple lasers in one track enables high processing speeds at low Relative speed between the laser beam and that of the workpiece. Also can hereby optimally adapt the processing speed to the time constant of Heat dissipation of the material can be adjusted. With longer processing times too much energy flows uselessly into the environment.

The housing 35 is closed gas-tight with a cover and a seal, both of which are not shown in the figures. A cylindrical tube 51 is flanged to the housing 35 in the region of the bore 47 and sealed by a seal 52 . The cylindrical tube contains an optical system as a transmission unit, namely two tubes 53 and 54 , each with an optical imaging system, which the eight laser beams F _D1 to F _D4 and F _R1 to F _R4 at the radiation exit 10 ( FIG. 1) onto the processing surface in the correct scale depict. There are preferably two optical imaging systems arranged one behind the other, since otherwise there would be a very large overall length or a very small distance between the objective lens and the processing surface, both of which are disadvantageous since a long beam path would have to be folded by means of a mirror and a too small distance between the objective lens and the processing surface could lead to too great a risk of contamination of the objective lens.

The beam path is shown in FIG. 3 as a side view. The basic beam _{path is} shown in FIG. 10 as a top view for the beam _packet F _HD1 to F _HD4 . The wavelength-dependent mirrors, the modulators and the strip mirror are not shown there. In the figures mainly plano-convex lenses are shown, but it is also possible to use other lens shapes in all figures, such as e.g. B. biconvex or concave-convex lenses or those with an aspherical shape. Lens systems, each consisting of several lens combinations, can also be used.

To transmit the laser energy as efficiently as possible and the heating To keep the optical components within limits are all in the different Versions of the laser radiation source occurring optical surfaces for anti-reflective coating of the wavelength range in question with the highest quality.

There are further advantageous solutions for the transmission unit in order to shorten the overall length of the transmission unit and still achieve a sufficiently large distance between the objective lens and the processing surface, as is shown in more detail in FIGS. 4 and 5, among others.

The lenses 55 and 56 can be connected to the tube 53 by screwing or gluing, but they can preferably be metallized at their edges and soldered to the tube 53 . The same applies to the lenses 57 and 61 in the tube 54 . This results in a gas-tight sealing of the lenses and good heat transfer from the lenses to the tubes. The tube 54 is preferably sealed gas-tight with a seal 62 with respect to the cylindrical tube 51 . The same conditions apply to the room 63 with regard to the tightness and cleanliness as for the room 44 and also for the rooms 64 and 65 within the tubes 53 and 54 . The chambers 66 and 67 are preferably connected to the spaces 44 and 63 via bores 71 . The tubes 53 and 54 can preferably have openings 72 .

An intercepting arrangement 73 for rendering the laser radiation harmless, which should not have any machining effect on the processing surface and which has a highly reflecting mirror 74 and a diverging lens (concave lens) 75 , projects into the space 63 . The interception arrangement 73 is inserted with a seal 76 , and the concave lens 75 , which can also be replaced by another optical element, for example a glass plate, is glued into the interception arrangement or preferably metallized in its edge zone and soldered to the interception arrangement for better heat dissipation. The space 63 is thus sealed off from the environment in a gastight manner. The measures described result in that the entire interior of the multi-part receptacle is sealed gas-tight from the environment. The spaces 44 , 63 , 64 and 65 and the chambers 66 and 67 , that is to say the entire interior of the multi-part receptacle, can preferably be evacuated or filled with a protective gas. The rooms and chambers should be as free as possible from those components that secrete gases or particles because dirt could settle on the highly stressed optical surfaces, which would lead to the premature failure of the arrangement. For this reason, the seals to be used are also required not to secrete particles or gases. During assembly, great importance is attached to the purity of the parts to be assembled and the environment until the optical unit is closed. After the optical unit has been closed, the entire interior of the multi-part receptacle can be evacuated via the valve 77 , or a protective gas can be introduced. The advantage of filling the interior with a protective gas is that it can be replaced more easily by connecting a gas bottle (not shown) via a pressure reducing valve during operation to valve 77 , from which gas can be refilled into the housing if required. A further advantage is that if a termination piece is to be removed from the housing and replaced by another for the replacement of a fiber laser, or if the housing or the cylindrical tube has to be opened by the user for any reason, one is constantly on during the process allow a small amount of the protective gas to flow through the housing in order to prevent dirt particles from entering the protected space. A small amount of the gas can also flow continuously through the housing and let it escape through openings 120 ( FIG. 3f), preferably in the vicinity of the objective lens, so that this flow also prevents contamination of the objective lens by such dirt particles that are released during the machining process. Evacuation or protective gas filling can also be dispensed with if one accepts the shorter life of the laser radiation source.

It is advantageous in the arrangement according to FIG. 3 that the angle between the beam packets of the original beam direction I _{0 of} the acousto-optical modulator and the deflected beam direction I ₁ is significantly increased by the imaging system from the lenses 55 and 56 , so that it is easy to use of the highly reflecting mirror 74 on the interception arrangement 73 to intercept the undesired radiation packet of the deflected beam direction. The mirror 74 is preferably made of metal and provided with a highly reflective layer in order to keep the heating due to absorbed laser energy low. For better heat dissipation, it is connected to the tube 51 via a strong flange of the interception arrangement 73 . The advantage of the arrangement according to FIG. 3 is that the optical components in the two tubes are subject to low requirements. You could even make both tubes completely the same. Another advantage is that the axes of the end pieces 26 are parallel to each other. The distance between the objective lens 61 and the processing surface 81 must not be too small, so that particles flying away from the material surface do not reach the objective lens. If it gets dirty, the laser energy that passes through is absorbed and destroyed and therefore unusable. In order to prevent contamination, a special mouthpiece 82 is arranged between the objective lens 61 and the processing surface 81 , which in the German utility model application "Arrangement for the Removal of Material by a Laser Radiation Source during Material Processing from a Processing area is removed ", sign of the applicant 98/1039 GM, is described.

The multi-part receptacle of the optical unit is mounted within the arrangement for material processing, for example on a prism 83, about the optical axis determined by the objective lens 61 , which corresponds to the axis of the tube, and is displaceable in the direction of the optical axis and, for example, with a tension band 85 or fixed in position with several straps. This enables the optical unit to be precisely delivered to the processing surface 81 . The track spacing of the individual processing tracks of the lasers on the processing surface 81 can be changed by the rotation. Outside the prism 83 is a plate 86 which has openings 87 through which a coolant can be pumped. The task of this plate 86 is to collect and derive the laser energy which is intercepted from the beam path and which is not intended to produce a processing effect. There is thermal insulation between the plate 86 and the tube 51 , 95 , 113 , but this is not shown in the figures. The plate is connected to the tube 51 , 95 , 113 via insulating flanges 91 . The flanges 91 also prevent laser radiation from escaping.

As a result of the high laser power, the optical elements will heat up in the beam path since they absorb a part, albeit very small, of the laser energy. The critical optical components are therefore preferably made of a material with better thermal conductivity, for example sapphire, instead of glass. The heat loss is dissipated when the connection surfaces of the optical components are metallized through the soldered connections to the sockets and to the housing. The housing is designed for better heat dissipation with cooling fins 92 , which can be cooled by a fan, not shown. It is also possible to enforce the housing 35 and the other components of the laser radiation source with bores, in particular in the critical areas on the lens mounts and mounts for the end pieces 26 , through which a coolant can be pumped, which is shown in FIGS. 3d and 3e is.

Since very high laser powers are required in material processing, as explained in the foregoing, it is essential according to the invention to keep the number of optical elements, in particular lenses, as small as possible in the beam path in order to avoid optical losses and the risk of Keep contamination of the optics, which would always lead to premature failure, as low as possible. It is also within the scope of the invention that the objective lens ( 61 , 103 and 112 ) is equipped with an exchangeable frame ( Fig. 3f) so that it can be quickly replaced by the user of the laser radiation source if necessary, be it that it is dirty during operation or that a different magnification is desired. It is also within the scope of the invention that measures are taken in the optical beam path that no laser energy can get back into the lasers. It is appropriate that the laser radiation does not hit the material to be processed perpendicularly, but at an angle, so that the radiation reflected on the material surface cannot return to the laser radiation source. Further, in Figs. 3, 4, 5 and 8, that is to be destroyed by laser radiation an inclined concave lens 75 into a sump consisting passed from an inclined plate 86 can be cooled. According to the invention, instead of the concave lens 75 , another optical component, for example a plate or a diaphragm, can also be used. This optical component is dimensioned in its effective diameter so that the laser radiation directed into the sump can just pass through, while such radiation that is reflected or scattered back from the sump is largely retained so that no energy is returned to the laser can reach.

According to the invention, the surface of the plate 86 , which is shown in the figures as a flat surface, can also be spherical or hollow and preferably roughened in order to absorb a maximum amount of radiation and to reflect or scatter a minimum of radiation.

It is within the scope of the invention to choose versions of the optical, mechanical and electrical arrangement for FIG. 3 which differ from the embodiment described. For example, one could focus all the parallel beam packets F _D1 to F _D4 and F _R1 to F _R4 with a lens on the processing surface in such a way that all processing points hit the same spot, which results in a very high power density, but not so good the shape of the processing spot, since all processing points lie on one another and are combined to form a common spot.

The principle of the described arrangement of laser outputs in several planes or in several tracks or in several tracks and in several planes or overlapping in one point also applies according to the invention to the laser beams incident on the processing surface 81 . According to this ordering principle, multiple tracks or multiple levels or multiple tracks and multiple levels of laser beams can also be arranged on the processing surface, or the laser beams can be arranged overlapping at one point.

In Fig. 3b it is shown how the spacing of the rays from the terminators can be changed in a direction, for example, to direct the rays from a plurality of levels by the same modulator. When the tracks are arranged in parallel, the imaging system shown with the cylindrical lenses 202 and 203 , also called cylinder optics, can be added analogously to an arrangement such as that of FIG. 3. If, however, the individual tracks are to run at an angle according to FIGS. 13 or 14, end pieces 94 according to FIGS. 7, 7a and 7b are preferably used. In this arrangement, too, the beams of the individual planes remain parallel; the fits of the end pieces 94 are intended to run parallel for this in the side view in FIG. 7a. If the axes of the ray bundles for the tracks run at an angle to one another, the cylinder optics with the lenses 203 and 203 can, for example, be added analogously to arrangements according to FIGS. 5 or 6. The beam bundles 144 emerging from the end pieces are directed onto the convex cylindrical lens 202 , which would combine the beams from the individual planes into a line with the length of the beam diameter. In the area of the focus, a concave cylindrical lens 203 with a shorter focal length than the cylindrical lens 202 has is attached such that its focus coincides with the focus of the cylindrical lens 202 . As a result, the rays leaving lens 203 become parallel again. The distances between the individual planes have, however, been reduced by the ratio of the focal lengths of the two cylindrical lenses compared to the distances that the beams had when they left the end pieces 26 , 94 . In the direction of the tracks, the distances between the beams have remained unchanged, since the cylindrical lenses have no effect in this direction. This results in elliptical beam cross sections in the modulator. The purpose of this arrangement is, for example, to make the total height of the 3 superimposed ellipses so small that they correspond approximately to the long axis of the ellipses, in order to create similar conditions in the channels of the acousto-optic modulator as with a round beam cross section similarly short switching times can be achieved, for example.

The cylinder optics ( 202 , 203 ) is shown in Fig. 3b between the end pieces ( 26 , 94 ) and the modulator ( 34 ). However, a wavelength- or polarization-dependent mirror 37 can be arranged in the beam direction before or after the cylinder optics. Cylinder optics ( 202 , 203 ) can also be arranged in the beam path after the modulator, before or after the strip mirror 46 . The intermediate image is preferably used in the beam path at the locations labeled "E" in FIG. 4a.

In Fig. 3c shows how the spacing of the beams can be changed from the terminators in both directions. A reducing intermediate image is given by means of the lenses 191 and 192 , so that the distance between the individual end pieces 26 , 94 may be greater than the distance between the individual modulator channels T1 to T4 on the multi-channel acousto-optic modulator 34 . The imaging ratio corresponds to the ratio of the focal lengths of the two lenses 191 and 192 . The intermediate image is preferably formed telecentrically, in that the distance of the lens 191 to the lenses 133 of the end pieces 26 and 94 and to the crossover point 193 is equal to their focal length and in that the distance from the crossover point 193 to the lens 192 and the distance of the lens 192 to Modulator crystal 34 is equal to their focal length. By adjusting the distance between the two lenses, however, it can also be achieved that the rays emerging from the lens 192 no longer run parallel, but at an angle to one another, in order to connect a beam path according to FIG. 11 or FIG. 12 to it. The intermediate image ( 191 , 192 ) is shown in Fig. 3c between the end pieces ( 26 , 94 ) and the modulator ( 34 ). However, a wavelength-dependent or polarization-dependent mirror 37 can be arranged in the beam direction before or after the intermediate image. An intermediate image ( 191 , 192 ) can also be arranged in the beam path after the modulator, before or after the strip mirror 46 . The intermediate image is preferably used in the beam path at the locations labeled "E" in FIG. 3a.

In Fig. 3d, sockets 29 are shown in a housing 145 for a plurality of conically shaped end pieces 26 , as shown in Fig. 13 and which have a cylindrical shape and two cylindrical fits, of which the fit facing the lens 133 has a conical shape . An arrangement in 2 parallel planes is provided in sections. The axes of the end pieces can run parallel to or at an angle to one another in the direction of the tracks. The housing 145 with the sockets 27 for the end pieces is part of the housing 35 , 93 , it can be made with it in one piece or made as a separate piece and connected to it in a gastight manner. In order to dissipate the heat loss, the housing 145 can, according to the invention, be provided with bores 87 through which a coolant is passed.

Fig. 3e shows a lens 101 whose version contains holes 87, the lens should preferably enclose a plurality of turns and are traversed by a coolant. With high power arrangements, the absorption of the optical medium of the lenses cannot be neglected. In addition, a small proportion of the radiation is scattered by each optical surface, even with the best coating, and absorbed by the frame parts. It is therefore advisable to cool the lens frames. It has already been mentioned that materials with high thermal conductivity and low absorption such as e.g. B. sapphire are advantageous. Sapphire also has the advantage that the lens surface does not scratch when cleaning due to the material's extreme hardness. It is also necessary to ensure good contact between the optical medium and the mount, which is advantageously done by metallizing the edge zone of the optical element and soldering 223 to the mount, since metallic solders have better heat conduction than glass solders, especially since they only do so certain types of glass can be used.

Fig. 3f shows a section through a socket 118 according to the invention for the objective lens 61, 103, 112, which is fixed, for example with a thread on the tube 65, 96, or socket 116 and sealed with a seal 125th The objective lens can be glued into the mount or preferably metallized at its edge and soldered into the mount ( 223 ). The mount can be provided with one or more bores 120 through which a protective gas, which comes from the interior of the optical unit 8 , flows out and is guided, for example, by means of a groove 119 over the side of the objective lens 61 , 103 , 112 facing the machining surface to avoid contamination of the objective lens by material particles or gases that are released during processing.

In FIG. 4, another multi-piece receptacle for the optical unit of a laser radiation source is shown, which differs in the following points from that of Fig 3 illustrated.:

• - housing 93 ,
• - end pieces 94 ,
• - cylindrical tube 95 ,
• - tube 96 and
• - highly reflective mirror 97

The housing 93 has sockets 29 that match the end pieces 94 . The end pieces 94 preferably correspond to those of FIGS. 7, 7a and 7b, the axes of the ray bundles do not run parallel when the end pieces are lined up in the relevant beam packets, but rather towards the center of the concave lens 101 , which is shown in the top view in FIG. 11. However, other shapes of the end pieces can also be used if it is ensured that the sockets 29 are arranged at an appropriate angle for this purpose, as shown for example in FIG. 13. Imaging optics, which consist of 3 lenses, are located in the tube 96 as a transmission unit, namely a diverging lens, that is to say a concave lens 101 and two converging lenses, that is to say convex lenses 102 and 103 , the lens 103 preferably being designed as an exchangeable objective lens. The statements made under Fig. 3 apply to the assembly of the lenses with regard to tightness and heat dissipation, as does the choice of material with regard to heat conduction. The tube 96 can be evacuated in the space between the lenses 101 and 102 or filled with a protective gas or preferably connected to the space 105 via a bore 104 , which in turn is connected to the space 107 via a bore 106 . The space 107 is connected to the space 111 via the bore 47 , which in turn is gas-tight, as described in FIG. 3. The space between the lenses 102 and 103 can be connected to the space 105 via a bore 72 , 104 ( FIG. 3f), in particular if the mount of the lens is sealed gas-tight or, as described under FIG the optical unit flows and exits near the objective lens, as shown in Fig. 3f. The entire interior of the receptacle for the optical unit, comprising the rooms 111 , 105 , 107 , is preferably evacuated or filled with a protective gas or through which a protective gas flows, as was described in detail under FIG. 3. The unwanted beams are intercepted with a highly reflective mirror 97 . The distance between the highly reflecting mirror and the modulators is kept large enough to achieve a sufficient spatial separation of the radiation packets I ₀ and I ₁ . The optical beam path of the transmission unit in FIG. 4 represents a side view, in FIG. 11 there is a basic beam path for a top view of FIG. 4 a 33113 00070 552 001000280000000200012000285913300200040 0002019840927 00004 32994. The beam path of the lenses 101 and 102 corresponds to that of an inverted Galileo telescope; but it can also be designed as an inverted Kepler telescope if the short focal length concave lens 101 is exchanged for a convex lens. Such telescopes are described in the textbook "Optics" by Klein and Furtak, Springer 1988, pp. 140 to 141. The advantage of the arrangement according to FIG. 4 is that only 3 lenses are required for the transmission unit. The disadvantage that the beams of the individual end pieces do not run parallel is eliminated by end pieces according to FIGS. 7, 7a and 7b.

A lens 55 could also be used to redirect the beams in the desired direction, as shown in FIG. 10. Then the individual laser beam bundles between the end pieces 26 and the lens 55 , which is arranged as in FIG. 3, would run parallel to one another and there would be no difference with respect to the housing and the end pieces or their arrangement from FIG. 3 In addition to the deflecting effect, lens 55 also exerts a collecting effect on the individual beam bundles, the same conditions would not arise at the location of the concave lens 101 as in FIG. 11. However, this can be done by a different adjustment of the distance of the fiber 28 or the laser fiber 5 to compensate for the lens 133 or a modification of the lens 133 in the end pieces 26 , ie the beam cone of the laser beams from the individual end pieces would each be set such that a sharp image would result on the processing surface at the points B ₁ to B _n . It is also possible according to the invention to combine the lenses 102 and 103 into a single, common lens. Then there is a transmission unit with only 2 lenses.

A special mouthpiece 82 is provided on the multi-part receptacle, which is intended to prevent contamination of the objective lens 112 and which is described in the German utility model application "Arrangement for Removing Material by a Laser Radiation Source during Material Processing from a Machining Surface", which is filed in parallel with the present application is removed ", sign of the applicant 98/1039 GM.

Fig. 5 shows a multi-part recording, which is made much more compact than that of Figs. 3 and 4. An objective lens 112 is used as the transmission unit in connection with a mirror arrangement, which can be exchanged to achieve different imaging scales. Fig. 5 differs from Fig. 4 in the following points. The cylindrical tube 95 is replaced by an eccentric tube 113 . The tube 96 is preferably replaced by a plate 114 with a concave mirror 115 and a holder 116 with an objective lens 112 and a highly coated plate 117 . The interception unit 73 is provided with a curved (convex) mirror 121 above the highly reflecting mirror 97 . The eccentric tube is connected to the housing 93 on one side. A seal 52 ensures the required tightness. In the eccentric tube 113 , a plate 114 is inserted, which contains a passage for the radiation packets I ₀ and I ₁ , and carries the concave mirror 115 , the heat loss of which is thus dissipated well to the eccentric tube. The eccentric tube has two axes, which are preferably parallel to one another, namely firstly the axis of symmetry of the incoming radiation packets with the direction 10 , which are directed towards the curved mirror, and secondly the axis between the concave mirror and the objective lens 112 , which can be regarded as an optical axis of symmetry for the emerging laser radiation . According to the invention, the beam path is folded by means of the two mirrors 121 and 115 . The curved mirror 121 is preferably made of metal. It is closely connected to the highly reflective mirror 97 and is preferably made in one piece with it. The convex surface of the curved mirror can be spherical or aspherical in shape. The mirror 115 is concave, that is, a concave mirror. Its surface can be spherical, but is preferably aspherical. It is preferably made of metal. Metal has the advantage of good heat dissipation. Furthermore, there is a considerable advantage in the production of metal in the production of aspherical surfaces, which in this case, like spherical and flat surfaces, can be produced by known diamond polishing turning processes. As a result, the highly reflective mirror 97 and the curved mirror 121 can be produced in one piece and preferably in one operation with the same shape of the surface and mirrored together, which is particularly simple to manufacture and very advantageous for the positional stability of the curved mirror, because when modulating the laser energy by means of the acousto-optical modulator, it hits either the curved mirror 121 or the highly reflecting mirror 97 . The heat loss generated remains the same in any case and the curved mirror maintains its temperature and thus its position, which is very important since it is preferably designed with a short focal length and therefore the imaging quality of the arrangement is very dependent on its exact position. In this case, the curved mirror 121 has taken over the function of the highly reflecting mirror 97 in an advantageous manner. However, the highly reflecting mirror 97 can also have a different shape of the surface than the curved mirror 121 and can be, for example, a plane mirror. The beam path is similar to that of an inverted Herschel mirror telescope, which instead of the curved mirror contains a convex lens, and is described in more detail in FIG. 12. Mirror telescopes are described in the "Textbook of Experimental Physics Volume III, Optics" by Bergmann-Schaefer, 7th edition, De Gruyter 1978, on page 152. You can also replace the curved mirror with a short focal length concave mirror. This would slightly increase the overall length and other beam cones of the beams emerging from the end piece would have to be set in order to obtain a sharp image in the image plane. The intercepting arrangement 73 is attached to the eccentric tube in a gas-tight manner by means of a seal 76 , via which the undesired laser energy, as described under FIGS . 3 and 4, is diverted to a cooling plate 86 with bores 87 and rendered harmless. It is also possible to intercept the undesired laser radiation from the radiation packet I at the location of the plate 114 and to render it harmless.

The space 111 in the housing 93 is connected to the hollow space 123 via the bore 122 . Both rooms can be evacuated or preferably filled with a protective gas or flowed through by a protective gas, as already described. At the end of the eccentric tube 113 , which lies opposite the housing 93 , the mount 116 is attached, which receives the exchangeable objective lens 112 . A seal 124 closes the cavity 123 gas-tight. Furthermore, the socket can receive a tempered plate 117 , the edge of which is preferably metallized and which is preferably soldered gas-tight to the socket. Your task is to keep the cavity 123 gas-tight if the objective lens has been removed for cleaning or if an objective lens with a different focal length is to be used in order to produce a different imaging scale. The space between the objective lens 112 and the highly coated plate 117 can also be connected to the space 123 via a bore 104 , in particular when a protective gas which flows through the entire optical unit as described in FIG Near the objective lens 112 emerges, which is shown in FIG. 3f. The highly coated plate 117 can, however, also contain optical correction functions, as are known from the Schmidt optics known from the literature, in order to improve the optical imaging quality of the arrangement. However, it is also possible to omit the highly coated plate, in particular if it contains no optical correction function and the objective lens has been inserted in a gas-tight manner or if a protective gas has flowed through it to ensure that no dirt can enter the space 123 when the objective lens is changed.

A special mouthpiece 82 is provided on the multi-part receptacle, which is intended to prevent contamination of the objective lens 112 , as described in the German utility model application "Arrangement for Removing Material by a Laser Radiation Source during Material Processing from a Processing area is removed ", sign of the applicant 98/1039 GM, is described.

The eccentric tube can be provided with cooling fins 92 , which can be blown by a fan, not shown, in order to better dissipate the heat loss to the environment. The multi-part receptacle is mounted in a prism so as to be rotatable about an axis defined by the objective lens between the concave mirror and the objective lens in order to make the track spacing adjustable as described under FIG. 3 and to set the correct distance to the processing surface 81 . The multi-part receptacle can be fixed with a strap 85 .

Furthermore, all descriptions given for FIGS . 3, 3a and 4 apply mutatis mutandis.

It is also possible, however, to replace the acousto-optical modulator 34 with other modulators, e.g. B. use so-called electro-optical modulators. Electro-optical modulators are described under the terms "laser modulators", "phase modulators" and "Pockels cells" on pages F16 to F33 of the general catalog G3, order no. 650020 from Laser Spindler & Hoyer, Göttingen. Multi-channel electro-optical modulators have also been used, which is shown in the publication "The Laser in the Printing Industry" by Werner Hülsbuch, W. Hülsbusch, Constance, on page 523 in Figure 8-90a. If single or multi-channel electro-optic modulators are used in connection with a birefringent material, then each laser beam can be split into two beams, which can be modulated separately via further modulators. Such an arrangement is also referred to in the literature as an electro-optical deflector.

But you can also modulate the fiber laser directly. Such directly modulatable fiber lasers, which have a separate modulation input, are offered, for example, by the company IPG Laser GmbH D-57299 Burbach, under the name "Model YPLM Series". The advantage is that the modulators and the associated electronics can be omitted, as shown in FIG. 13.

In FIG. 6, an embodiment of a terminator 26 (terminator) for a fiber shown. Such end pieces can advantageously be used for coupling out the laser radiation from a fiber, as described in the German patent application "End piece for optical fibers", sign of the applicant 98/1037, which is filed in parallel with the present application, and in the parallel run, simultaneously with the present application filed German utility model application "end piece for optical fibers", sign of the applicant 9811037 GM, are described. This end piece 26 can in principle be used for all applications in which it is important to precisely couple the rays of light emerging from a fiber 28 or a laser fiber 5 belonging to a fiber laser with a detachable connection. It is also possible with the aid of this end piece to produce a precisely detachable connection of the fibers 5 , 28 with the rest of the optics. The housing has one or more outer fits 134 with which the housing can be inserted precisely in a socket 29 . The end of the fiber 28 or the laser fiber 5 is received at one end of the housing and guided in the opening 130 within the housing. A short focal length lens 133 is attached to the other end of the housing. Means for adjusting the position of the fiber 28 or laser fiber 5 within the closure piece can be provided in order to adjust the position of the fiber 28 or laser fiber 5 relative to the lens 133 within the closure piece and with respect to the fits 134 . The position of the lens relative to the fiber can also be adjusted. The aim of the adjustment is to ensure that the beam 144 emerging from the lens 133 is brought into a predetermined axis and focus position with a defined cone.

In Fig. 6a shows a cross section through the end piece 26 in the region of the adjusting screws.

The embodiment of the end piece 26 shown in FIG. 6 has a square or rectangular cross section, in which all the opposite outer surfaces run parallel and can be fits 134 . In order to prevent the optical surfaces on the optical fiber and the side of the lens 133 facing the optical fiber from becoming contaminated by particles in the surrounding air, the connections in FIGS. 6, 6a, 7, 7a and 7b between the Lens 133 and the housing and between the adjusting screws and the housing are hermetically sealed. FIG. 7 shows an embodiment of the end piece 94 with a rectangular cross section, two opposite outer surfaces being trapezoidal and two opposite outer surfaces running parallel to one another. All opposite outer surfaces can also run in a trapezoidal shape with respect to one another. The outer surfaces can be fits 134 .

A longitudinal section is shown in FIG. 7a and a cross section through the end piece according to FIG. 7 is shown in FIG. 7b.

It is fundamentally possible to combine several of the end pieces described above in several tracks next to one another and in several levels one above the other to form a package. It is also possible to design the shape of the end pieces and the associated mounts differently than shown in the figures, for example a cylindrical shape with a cylindrical and a conical fit according to the mounts in FIG. 3d or an exclusively cylindrical fit can be used, or a cylindrical shape of the end piece, for example, rectangular or trapezoidal fits according to FIG. 6 or 7 can be obtained.

In FIG. 8 illustrates an arrangement comprising an electro-optical modulator 168th In an electro-optical modulator, for example, the direction of polarization of the laser radiation that is not desired for processing is rotated from the incident beam 163 (P _b ) and then in a polarization-dependent beam splitter, which is also referred to as polarization-dependent mirror 169 , that separates the laser radiation P _b that is not desired for processing and into a sump, for example into a heat exchanger, which may consist of a cooled plate 86 . The radiation P _a desired for processing is not rotated in the direction of polarization and is supplied to the processing surface via lens 165 . In the exemplary embodiments according to FIGS. 3, 4 and 5, the single or multi-channel acousto-optical modulators 34 can be replaced by corresponding single or multi-channel electro-optical modulators. Likewise, in the exemplary embodiments according to FIGS. 3, 4 and 5, the highly reflecting mirror 74 , 97 can be replaced by the polarization-dependent mirror 169 ( FIG. 18a), which results in an interception arrangement 78 and in which the polarization-dependent mirror is in the desired range for processing Beam path extends into it.

FIG. 9 shows a top view of a four-channel acousto-optical deflector or modulator, in which the distance from channel to channel is 2.5 mm, for example. In the description of FIGS . 3, 3a, 4 and 5 it is mentioned that the space 44 or 111 , in which the modulators are arranged, should be as free as possible from those components which secrete particles or gases, because this creates particles could settle on the highly stressed optical surfaces, which would lead to the premature failure of the arrangement. For this reason, the electrical components of the arrangement in FIGS. 9 and 9a are arranged on a separate printed circuit board 171 which only projects into the sealed space with two arms and which makes the electrical connections to the piezoelectric sensors 45 . The circuit board 171 is preferably sealed off from the modulator housing 172 by means of a solder joint 173 . Instead of a printed circuit board, another line arrangement can also be used. For example, each high-frequency channel can be connected by its own shielded cable. The modulator housing 172 contains an access opening 174 to the electrical components. The modulator crystal 34 can be metallized on its base and is preferably attached to the modulator housing by means of a solder joint or an adhesive 175 . A connection 176 to a cooling system can be located directly below the fastening point in order to remove the heat loss through the openings 87 by means of a coolant. The modulator housing 172 is preferably closed by a cover 177 which carries the electrical connections 181 and also contains the connections for the cooling system, but this is not shown. A seal 43 ensures that the modulator housing 172 is inserted in a gastight manner into the housing 35 or 93 of FIGS . 3, 3a, 4 and 5 and is fastened by means of the connection 42 .

It is possible to attach the electro-optic modulator 168 to the modulator housing ( 172 ) in a similar manner and to contact it via the printed circuit board 171 .

FIG. 10 shows the basic beam path for the exemplary embodiment in FIG. 3 for the beam bundles 144 of the associated fiber lasers F _HD1 to F _HD4 . The beam bundles of the fiber lasers F _VD1 to F _VD4 are partially congruent with the drawn beams, but according to the invention have a different wavelength and, as can be seen from FIG. 4a, are transmitted via a wavelength-dependent mirror 37 (not shown in FIG. 10) with the beam packet F _HD1 to F _{HD4 combined} to form the radiation _packet F _D1 to F _D4 . Furthermore, the beam packets of the fiber lasers F _VR1 to F _VR4 and F _HR1 to F _HR4 are not shown in FIG. 10, which, as can be seen from FIG. 3a, are also combined to form the beam packet F _R1 to F _R4 via a wavelength-dependent mirror. As can be seen from the arrangement of the strip mirror 46 in FIG. 4a, the beam bundles of the beam packet F _R1 to F _R4 in FIG. 10 would be offset by half a track distance from the drawn beams. Thus, the complete beam path contains a total of 8 beam bundles instead of the drawn 4 beam bundles, which result in a total of 8 separate tracks on the processing area. Only the two beams 144 of the fiber lasers F _HD1 and F _HD4 are shown in FIG. 10. As already mentioned, however, more tracks can also be arranged, for example the number of tracks on the processing area can also be increased to 16 separately modulatable tracks. This arrangement enables particularly simple control and good shaping of the machining spot on the machining surface by digital modulation of the respective laser, ie the laser is operated in only two states by switching it on and off.

This type of digital modulation only requires a particularly simple modulation system. In Fig. 10, the modulators 34 and the strip mirror are not shown 46th For better illustration, the cross section of the beam 144 from the end piece of the fiber laser F _HD1 , which is congruent with the beam F _D1 after passing through the wavelength-dependent mirror, is designed with hatching. The presentation, like all others, is not to scale. The two drawn-ray beam 144 arise on the processing surface 81, the working points B ₁ and B ₄ that contribute to the structure of the processing spot 24 and 81 generate corresponding processing traces on the processing surface. The axes of the end pieces 26 and the beams 144 of the individual fiber lasers run parallel to one another in FIG. 10. The beam cones of the end pieces, ie the shape of the beam 144 , are shown to be slightly divergent. In the figure, a beam waist within lens 133 is assumed. The divergence angle is inversely proportional to the diameter of the beam in the associated beam waist. The position of the beam waist and its diameter can, however, be influenced by changing the lens 133 in the end piece 26 and / or its distance from the fiber 28 or the laser fiber 5 .

The beam path is calculated in the known manner, see technical explanations on pages K16 and K17 of the general catalog G3, order no. 650020 from Laser Spindler & Hoyer, Göttingen. The aim is that the processing points B ₁ to B _n on the processing surface 81 become beam waists in order to obtain the highest power density in the processing points. With the help of the two lenses 55 and 56 , beam waists and track distances from the object plane 182 , in which the lenses 133 of the end pieces 26 are located, are depicted reduced in accordance with the ratio of the focal lengths of the lenses 55 and 56 in an intermediate image plane 183 . In this case, if the distance of the lens 55 from the end piece 26 and the crossover point 184 is equal to its focal length and if the distance of the lens 56 from the intermediate image plane 183 is equal to its focal length and its distance from the crossover point 184 , a so-called is obtained telecentric imaging, ie in the intermediate image plane the axes of the beams belonging to the individual tracks are again parallel. However, the divergence has increased significantly. The preferably telecentric imaging has the advantage that the diameter of the subsequent lenses 57 and 131 need only be insignificantly larger than the diameter of a beam. In a second stage, the lenses 57 and 61 reduce the image from the intermediate image plane 183 to the processing surface 81 in the manner described. A preferably telecentric image, namely that the axes of the individual bundles of rays run parallel between the objective lens 61 and the machining surface 81 , has the advantage that changes in the distance between the machining surface and the objective lens bring no change in the track spacing, which is very important for precise machining . The imaging does not necessarily have to take place in two stages, each with two lenses, as described, there are other arrangements which can also produce parallel beam axes between the objective lens and the processing surface, as shown in FIGS. 11 and 12. Deviations in the parallelism of the beam axes between the objective lens 61 and the processing surface 81 can also be tolerated as long as the result of the material processing is satisfactory.

In Fig. 11 is a principal beam path to the embodiment of Fig. Specified. 4 The representation is not to scale. As already in FIG. 10, the two beam bundles 144 of the lasers F _HD1 and F _{HD4 are} only a subset of the beam bundles of all existing lasers in order to explain the principle. In contrast to FIG. 10, however, in FIG. 11 the axes of the individual beam bundles of the end pieces are not arranged in parallel, but at an angle to one another, which is shown in more detail in FIGS. 13 and 14 and advantageously by end pieces 94 according to FIG. 7 , 7a and 7b is reached. With this arrangement, the individual beams 144 would cross one another in a manner similar to that in FIG. 10, without the need for a lens 55 . In the area of the imaginary crossing point, the short focal-length diverging lens, that is, a concave lens 101, is inserted, which bends the incoming beams as shown and makes the beams divergent, ie widened. The convex lens 102 is preferably arranged at the point of intersection of the axis rays and, together with the lens 101, forms an inverted Galilean telescope. This converts, for example, parallel input beams into parallel output beams with an enlarged diameter between the lenses 102 and 103 . As already described, the desired parallelism of each input beam can be carried out by a suitable choice of focal length and distance of the lens 133 from the fiber 28 or laser fiber 5 in the end pieces 26 , 94 . The objective lens 103 focuses the enlarged beams on the processing surface 81 to the processing points B ₁ to B ₄ , which contribute to the construction of the processing _spot 24 and generate corresponding processing tracks on the processing surface 81 . By changing the focal length of the lens 103 , the imaging scale can be changed in a simple manner. It is therefore advantageous if the lens 103 is designed as an exchangeable objective lens. If the position of the lens 103 is chosen so that the distance between the lenses 102 and 103 corresponds to the focal length of the lens 103 , the axes of the beams between the lens 103 and the working surface are parallel and give constant distances of the tracks on the working surface, too when the distance between the objective lens and the processing surface changes.

FIG. 12 shows the basic beam path for the exemplary embodiment in FIG. 5. As in all other figures, the representation is not to scale. The beam path is very similar to that of FIG. 11, with the difference that instead of the lens 101 a curved mirror 121 and instead of the lens 102 a concave mirror 115 are used. Due to the resulting folding, the beam path is considerably shorter. The beam path corresponds approximately to that of an inverted mirror telescope. Mirror telescopes are independent of the wavelength, which is advantageous when using lasers with different wavelengths. The imaging errors can be reduced by using aspherical surfaces or corrected with an optical correction plate 117 , which is not shown in FIG. 12, however. It is advantageous if the focal length of the objective lens 112 is equal to its distance from the concave mirror. Then the axes of the beams between the objective lens 112 and the machining surface 81 become parallel and result in constant distances between the tracks on the machining surface, even when the distance between the objective lens and the machining surface changes. In addition, there is an advantageously large distance from the objective lens to the processing surface.

An arrangement with several lasers is shown in FIG. 13, in which the individual laser outputs in the form of the end pieces 26 are arranged on a circle segment and aim at a common crossover point 185 . This arrangement is particularly suitable for directly modulatable lasers, since this results in very little effort. In such an arrangement, the imaging on the processing surface 81 can take place with only a single lens 186 . However, an arrangement according to FIGS. 4 or 5 can also be used for imaging. The beam cones of the beams from the end pieces are set in such a way that a beam waist and thus a sharp image result for all lasers on the processing surface 81 .

FIG. 14 shows a variant of FIG. 13. There are 4 fiber lasers F _HD1 , F _HD2 , F _HD3 , F _HD4 with their end _pieces 94 , which are described in more detail in _FIGS . 10, 10a and 10b, lined up on a segment of a circle. Due to their shape, the end pieces 94 are particularly suitable for stringing together. Since no directly modulatable fiber lasers are used here, a four-channel acousto-optical modulator 34 is inserted. The piezoelectric sensors 45 can, as shown in FIG. 14, also be arranged on a segment of a circle, but they can also be arranged in parallel, as shown in FIG. 14a, as long as the beams are still adequately detected by the acoustic field of the piezoelectric sensors 45 become. Instead of the lens 186 , a transmission unit as described in FIGS. 4 and 5 is advantageously used.

Claims (101)

1. Laser radiation source of high power density and high energy, preferably for material processing, with an optical unit for shaping the laser beam on a processing surface, characterized in that
several diode-pumped fiber lasers (fiber lasers) ( 2 ) are provided, the outputs of which are connected by means of end pieces ( 26 , 94 ) to an optical unit ( 8 ) for shaping the laser beam, the outputs of the end pieces in a first part and the optical unit in the first Part and are arranged in a second part of a multi-part receptacle,
the optical unit ( 8 ) has a modulation unit ( Fig. 3a, Fig. 9, Fig. 9a), at the input of which the output beams of the individual fiber lasers ( 2 ) are directed and through which the individual laser beams are modulated,
as summarized from the modulation unit (Fig. 3a, Fig. 9, Fig. 9a) exiting laser beams by means of the optical unit (8) and are bundled such that the beams impinge on the working surface (81),
the optical unit ( 8 ) for shaping the laser beam has a transmission unit for transmitting the laser beams emerging from the end pieces to the processing surface ( 81 ) and that
In order to render the unwanted laser radiation harmless, which is not intended to produce a processing effect on the processing surface ( 81 ), a trap arrangement ( 73 , 78 ) is provided by which the undesired radiation is kept away from the processing surface ( 81 ). 2. Laser radiation source according to claim 1, characterized in that the transmission unit is designed in two stages and is arranged in the second part of the multi-stage receptacle, which is designed as a tube ( 51 ), the first stage being in the converging lens ( 133 ) of the end pieces ( 26 , 94 ) formed beams ( 144 ) reduced in size to an intermediate image plane ( 183 ) and the second stage transmits the beams of the intermediate image plane ( 183 ) reduced to the processing surface ( 81 ). 3. Laser radiation source according to one of claims 1 or 2, characterized in
that a first tube ( 53 ) with two converging lenses ( 55 , 56 ) is provided at the end of the tube ( 51 ) flanged to the first part of the multi-stage receptacle designed as a housing ( 35 ) ( FIG. 3), the is attached centrally to the beam axis at the end of the tube ( 51 ) facing the housing, and inside the tube at its ends, by means of which an intermediate image ( 183 ) is generated within the tube ( 51 ),
that at the other end of the tube ( 51 ) facing the processing surface, a second tube ( 54 ) with two converging lenses ( 57 , 61 ) is provided, which is centered on the beam axis at the end of the tube facing the processing surface ( 81 ) ( 51 ) and inside the tube at its ends, through which a processing spot ( 24 ) is generated on the processing surface ( 81 ) and that
the laser radiation, which is not intended to produce a processing effect, by means of a mirror ( 74 , 169 ) which is arranged between the first tube ( 53 ) and the second tube ( 54 ), into the arrangement ( 73 , 86 ) for intercepting and rendering harmless Laser radiation, which is not intended to produce a processing effect on the processing surface ( 81 ), is deflected. 4. Laser radiation source according to one of claims 1 to 3, characterized in that
in the beam path ( Fig. 10) after the converging lenses ( 133 ) of the end pieces ( 26 , 94 ), which are arranged in one or more planes and in one or more tracks 1 to n ( Fig. 3b), a first transmission unit with a converging lens ( 55 ) and a converging lens ( 56 ) with a smaller focal length than the converging lens ( 55 ) is arranged, through which the rays emerging from the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) ( 144 ) whose axes of symmetry in the individual tracks run approximately parallel to one another, are deflected such that the rays intersect at one location ( 184 ) and that the deflection of the converging lens ( 55 ) is canceled by the converging lens ( 56 ), with an intermediate image plane ( 183 ) following in the beam path in the ratio of the focal lengths of the lenses ( 55 and 56 ), a reduced image of the rays ( 144 ) emerging from the converging lenses ( 133 ) of the end pieces ( 26 ) is formed and the rays n bundles have an enlarged divergence angle in relation to the focal lengths and that
a second transmission unit with a convergent lens (57) and a convergent lens (61) with a small focal length is arranged as the converging lens (57) in the beam path after the intermediate image plane (183) through which the reduced image of the radiation beam from the intermediate image plane (183) to the Processing area ( 81 ) is transferred, each beam emerging from the converging lenses ( 133 ) of the end pieces ( 26 ) generates a processing point (B ₁ to B _n ). 5. Laser radiation source according to one of claims 1 to 4, characterized in that
the distance between the lens ( 55 ) and the crossover point ( 184 ) is approximately equal to the focal length of the lens ( 55 ),
the distance between the crossover point ( 184 ) and the lens ( 56 ) and between the lens ( 56 ) and the intermediate image plane ( 183 ) is approximately equal to the focal length of the lens ( 56 ),
the distance between the intermediate image plane ( 183 ) and the lens ( 57 ) and the distance between the crossing point ( 187 ) and the lens ( 57 ) is approximately equal to the focal length of the lens ( 57 ) and that
the distance between the crossover point ( 187 ) and the lens ( 61 ) and between the processing surface ( 81 ) and the lens ( 61 ) is approximately equal to the focal length of the lens ( 61 ) and that the distances between the lenses are chosen so that the axes of symmetry the bundles of rays that appear on the processing surface ( 81 ) are approximately parallel to one another. 6. Laser radiation source according to claim 1, characterized in that the transmission unit consists of a diverging lens ( 101 ) and at least one converging lens ( 102 , 103 ), the diverging lens ( 101 ) in the converging lens ( 133 ) of the end pieces ( 26 , 94 ) The beam ( 144 ) formed is expanded and the converging lens or converging lenses ( 102 , 103 ) focuses the expanded beam and transfers it to the processing surface ( 81 ). 7. Laser radiation source according to claim 6, characterized in that
in the second part of the multi-stage receptacle designed as a tube ( 95 ), between the arrangement ( 73 , 86 ) for intercepting and rendering harmless the laser radiation and the end of the tube which faces the processing surface ( 81 ) within the tube in the beam path the tube ( 96 ), which contains the transmission unit, extends in the longitudinal direction of the tube and is held centrally within the tube,
the transmission unit having a diverging lens ( 101 ) which is arranged at the end of the tube which faces the housing ( 93 ) and receives and expands the laser radiation which is intended to produce a machining effect,
wherein the transmission unit has a converging lens ( 102 ) which forms the expanded laser radiation into approximately parallel bundles of rays, and an objective ( 103 ) is provided on the end of the tube ( 96 ) facing the processing surface ( 81 ), onto which the laser radiation, on the one hand Machining effect is aimed, is directed, wherein the lens on the processing surface ( 81 ) generates a processing spot ( 24 ) and
the undesired laser radiation, which is not intended to produce a processing effect, being deflected into the arrangement ( 73 , 86 ) by means of a mirror ( 97 , 169 ) for intercepting and rendering the laser radiation harmless. 8. Laser radiation source according to one of claims 6 or 7, characterized in that
in the beam path ( FIG. 11) after the converging lenses ( 133 ) of the end pieces ( 94 ), which are arranged in one or more planes and in one or more tracks 1 to n ( FIG. 3b), a transmission unit with a diverging lens ( 101 ) and two converging lenses ( 102 and 103 ) are arranged, by means of which the bundles of rays ( 144 ) emerging from the collecting lenses ( 133 ) of the end pieces ( 94 ), the axes of symmetry of which in the individual tracks run at an angle to one another, are thus deflected and expanded, that the rays cross each other in the lens ( 102 ), the diverging beams ( 144 ) being directed approximately parallel through the lens ( 102 ) and leaving the lens ( 102 ) at an angle in each case, and that
A lens ( 103 ) is arranged in the beam path after the lens ( 102 ), through which the approximately parallel beams are focused on the processing surface ( 81 ), each beam emerging from the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) having a processing point (B ₁ to B _n ) generated. 9. Laser radiation source according to one of claims 6 to 8, characterized in that
the focal length of the diverging lens ( 101 ) is significantly smaller than that of the converging lens ( 102 ),
the distance between the lenses ( 103 ) and ( 102 ) is approximately equal to the focal length of the lens ( 103 ), and that
the distance between the processing surface ( 81 ) and the lens ( 103 ) is approximately equal to the focal length of the lens ( 103 ), the spacing of the lenses being chosen such that the axes of symmetry of the beams which impinge on the processing surface ( 81 ) are approximately are parallel to each other. 10. Laser radiation source according to claim 1, characterized in that the transmission unit consists of a convex mirror ( 121 ) and a concave mirror ( 115 ), the convex mirror being formed in the converging lens ( 133 ) of the end pieces ( 26 , 94 ) ( 144 ) expands and deflects and the concave mirror deflects the expanded beams, focuses and transmits them to the processing surface ( 81 ). 11. Laser radiation source according to claim 10, characterized in that
at the end of the second part of the multi-part receptacle designed as a tube ( 113 ), which is flanged to the first part of the receptacle designed as a housing ( 93 ), a plate ( 114 ) is provided which receives a concave mirror ( 115 ) and a bore ( 122 ) through which the laser radiation enters the tube ( 113 ) from the housing,
that at the other end of the tube ( 113 ) to which the arrangement ( 73 , 86 ) for intercepting and rendering harmless the laser radiation is attached, a curved mirror ( 121 ) is arranged, on which the through the opening ( 122 ) into the Pipe entering laser radiation strikes, the laser radiation that is supposed to produce a machining effect is reflected on the concave mirror ( 115 ) and the unwanted laser radiation that is not supposed to produce a machining effect is reflected in the arrangement ( 73 , 86 ) for intercepting and rendering the laser radiation harmless by means of the curved mirror ( 121 ) or a plane mirror ( 97 ) or a polarization-dependent mirror ( 169 ) ( Fig. 18a) is deflected, and that
at the end of the tube facing the processing surface ( 81 ) there is a lens ( 112 ) onto which the laser radiation which is to produce a processing effect is directed by means of the concave mirror ( 115 ), the lens on the processing surface ( 81 ) providing a processing spot ( 24 ) generated. 12. Laser radiation source according to claim 10 or 11, characterized in
that in the beam path ( Fig. 12) after the converging lenses ( 133 ) of the end pieces ( 94 ), which are arranged in one or more planes and in one or more tracks 1 to n ( Fig. 3a), a transmission unit with a curved mirror ( 121 ), a concave mirror ( 115 ) and a converging lens ( 112 ) through which the rays ( 144 ) emerging from the converging lenses ( 133 ) of the end pieces ( 94 ), the axes of symmetry of which lie at an angle to each other in the individual tracks, are deflected and expanded so that the beams cross over each other on the concave mirror ( 115 ), the diverging beams ( 144 ) being aligned approximately parallel by the concave mirror ( 115 ) and leaving the concave mirror at an angle, and that
A lens ( 112 ) is arranged in the beam path after the concave mirror ( 115 ), through which the approximately parallel beam bundles are focused on the processing surface ( 81 ), each beam bundle emerging from the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) having a processing point (B ₁ to B _n ) generated. 13. Laser radiation source according to one of claims 10 to 12, characterized in that
the focal length of the curved mirror ( 121 ) is significantly smaller than that of the concave mirror ( 115 ),
the distance between the concave mirror ( 115 ) and the curved mirror ( 121 ) is approximately equal to the sum of the focal lengths of the concave mirror and the curved mirror, and that
the distance between the processing surface ( 81 ) and the lens ( 112 ) is approximately equal to the focal length of the lens ( 112 ), the spacing of the lenses and mirrors being chosen so that the axes of symmetry of the beams that occur on the processing surface ( 81 ) , are roughly parallel to each other. 14. Laser radiation source according to one of claims 1 to 13, characterized in that the optical unit ( 8 ) has sockets ( 29 ) which receive the end pieces ( 26 , 94 ) of the laser so that the output beams of the lasers at the radiation exit ( 10 ) of the optical unit ( 8 ) for shaping the beam on the processing surface ( 81 ). 15. Laser radiation source according to claim 14, characterized in that the sockets ( 29 ) have mating surfaces for the fit or fits ( 134 ) of the end pieces ( 26 , 94 ) which are arranged so that the axes of symmetry of the converging lenses ( 133 ) End pieces ( 26 , 94 ) emerging laser beams are arranged in at least one track and / or one plane ( Fig. 3b). 16. Laser radiation source according to claim 15, characterized in that the axes of symmetry of the converging lenses ( 133 ) of the end pieces ( 26 ) emerging rays ( 144 ) in the individual planes are approximately parallel to each other. 17. A laser radiation source according to claim 15, characterized in that the axes of symmetry of the bundles of rays ( 144 ) emerging from the converging lenses ( 133 ) of the end pieces ( 26 ) run at an angle to one another in the individual planes. 18. Laser radiation source according to claim 15, characterized in that the mating surfaces of the sockets ( 29 ) for the fit or fits ( 134 ) of the end pieces ( 26 , 94 ) for the individual tracks and planes are arranged so that the axes of symmetry from the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) emerging laser beams ( 144 ) for the individual tracks and for the individual planes run at an angle to one another. 19. Laser radiation source according to claim 15, characterized in that the mating surfaces of the sockets ( 29 ) for the fit or fits ( 134 ) of the end pieces ( 26 , 94 ) for the individual tracks are arranged so that the axes of symmetry of the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) emerging laser beams run at an angle to each other, and that the mating surfaces of the sockets ( 29 ) for the fit or fits ( 134 ) of the end pieces ( 26 , 94 ) for the individual levels are arranged so that the The axes of symmetry of the laser beams emerging from the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) are parallel to one another. 20. Laser radiation source according to claim 15, characterized in that the mating surfaces of the sockets ( 29 ) for the fit or fits ( 134 ) of the end pieces ( 26 , 94 ) for the individual planes are arranged such that the axes of symmetry of the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) emerging laser beams ( 144 ) run at an angle to each other, and that the mating surfaces of the sockets ( 29 ) for the fit or fits ( 134 ) of the end pieces ( 26 , 94 ) for the individual tracks are so arranged that the axes of symmetry of the laser beams ( 144 ) emerging from the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) are parallel to one another. 21. Laser radiation source according to claim 15, characterized in that the sockets ( 29 ) have mating surfaces for the fit or fits ( 134 ) of the end pieces ( 26 , 94 ) which are arranged so that the axes of symmetry of the converging lenses ( 133 ) End pieces ( 26 , 94 ) emerging laser beams are parallel to each other. 22. Laser radiation source according to one of claims 1 to 21, characterized in that the modulation unit ( Fig. 3a, Fig. 9, Fig. 9a) has one or more separate modulators. 23. Laser radiation source according to one of claims 1 to 22, characterized in that the modulation unit ( Fig. 4a, Fig. 19, Fig. 19a) consists of one or more multi-channel modulators ( 34 ). 24. Laser radiation source according to one of claims 1 to 23, characterized in that electro-optical modulators and / or electro-optical deflectors ( 168 ) are used. 25. Laser radiation source according to claim 1 to 23, characterized in that acousto-optical modulators and or acousto-optical deflectors ( 34 ) are used. 26. Laser radiation source according to one of claims 1 to 25, characterized in that the optical unit ( 8 ) for shaping the laser beam in the region between the radiation inlet ( 9 ) and the radiation outlet ( 10 ) contains means for merging the individual laser beams ( 13 ). 27. Laser radiation source according to claim 26, characterized in that for merging the individual laser beams means for reducing the distance between the axes of symmetry of the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) emerging beams (beams of the laser outputs) ( 144 ) in the direction of Traces and / or in the direction of the planes are provided. 28. Laser radiation source according to claim 27, characterized in that at least one lens is provided as means for reducing the distance between the axes of symmetry of the beams of the laser outputs ( 144 ). 29. Laser radiation source according to claim 27, characterized in that two converging lenses ( 191 , 192 ) are provided as means for reducing the distance between the axes of symmetry of the beams of the laser outputs ( 144 ). 30. Laser radiation source according to claim 27, characterized in that a collecting lens ( 202 ) and a diverging lens ( 203 ) are provided as means for reducing the distance between the axes of symmetry of the beams of the laser outputs ( 144 ). 31. Laser radiation source according to claim 27, characterized in that spherical lenses ( 191 , 192 ) or cylindrical lenses ( 202 , 203 ) are provided. 32. Laser radiation source according to one of claims 29 to 31 thereby characterized in that the distance between the two lenses is approximately equal to the sum their two focal lengths. 33. Laser radiation source according to one of claims 29 to 32, characterized in that the distance between the two lenses is set so that the beams overlap in the modulator ( 34 ). 34. Laser radiation source according to claims 26 or 27, characterized in that mirrors and / or lenses and / or wavelength and / or polarization-dependent elements are used as means for merging the beams of the beams of the laser outputs ( 133 ). 35. Laser radiation source according to claim 34, characterized in that for Merge the beams from at least two laser outputs wavelength-dependent element is used.   36. Laser radiation source according to claim 35, characterized in that a filter ( 37 ) is used as the wavelength-dependent element, which transmits the radiation of one of the laser outputs and reflects the radiation of the other laser output. 37. Laser radiation source according to claim 34, characterized in that Merge the beams from at least two laser outputs with polarized radiation a polarization-dependent element is used. 38. Laser radiation source claim 37, characterized in that as polarization-dependent element uses a polarization-dependent mirror which transmits the polarization-directed radiation from one of the laser outputs and reflects the polarization-directed radiation from the other laser output. 39. Laser radiation source according to claim 34, characterized in that a strip mirror ( 46 ) is used to merge the beams of at least two laser outputs, which passes the beams of the laser outputs from a first direction and reflects the beams of the laser outputs from a second direction. 40. Laser radiation source according to one of claims 26 to 39, characterized in that the means for merging the beams in the beam direction are arranged before and or after the modulation unit ( Fig. 3a). 41. Laser radiation source according to claim 26, characterized in that one or more single-channel or multi-channel acousto-optical deflectors ( 34 ) are provided as means for combining the beams within the modulation unit ( Fig. 3a, Fig. 9, Fig. 9a). 42. Laser radiation source according to one of claims 1 to 41, characterized in that the transmission unit for transmitting the laser beams emerging from the end pieces to the processing surface ( 81 ) has at least one lens ( 165 , 186 , 197 ). 43. Laser radiation source according to one of claims 10 to 42, characterized in that a transparent plate ( 117 ) is provided between the concave mirror ( 115 ) and the processing surface ( 81 ). 44. Laser radiation source according to claim 43, characterized in that the transparent plate ( 117 ) is an optical correction plate. 45. Laser radiation source according to one of claims 2 to 44 thereby characterized in that the lenses are designed as lens systems. 46. Laser radiation source according to one of claims 10 to 45, characterized in that the mirrors ( 115 , 121 ) have spherical and / or aspherical surfaces. 47. Laser radiation source according to one of claims 10 to 46, characterized characterized in that at least one of the mirrors is made of metal. 48. Laser radiation source according to one of claims 1 to 47, characterized in that the transmission unit has an interchangeable lens ( 61 , 103 , 112 ). 49. Laser radiation source according to one of claims 1 to 48, characterized in that the emerging from the converging lenses ( 133 ) of the end pieces ( 26 , 94 ) beam ( 144 ) have an exit cone, which is due to the distance of the converging lens ( 133 ) to the fiber end within the end pieces ( 26 , 94 ) are adjustable so that there is an optimal sharpness for the processing points B ₁ to B _n on the processing surface ( 81 ). 50. Laser radiation source according to one of claims 1 to 49, characterized in that the interception arrangement ( 78 ) has a polarization-dependent mirror ( 169 ) arranged in the beam path, through which the unwanted laser radiation, which is not intended to produce a processing effect on the processing surface, from the processing surface ( 81 ) is kept away. 51. Laser radiation source according to one of claims 1 to 49, characterized in that the interception arrangement ( 73 ) has a deflection mirror ( 74 , 97 , 121 ) arranged in the beam path, through which the unwanted laser radiation, which is not intended to produce a processing effect on the processing surface, of the processing surface ( 81 ) is kept away. 52. Laser radiation source according to claim 51, characterized in that the deflecting mirror ( 74 , 97 , 121 ) is made of metal. 53. ( 113 ). Laser radiation source according to Claim 51 or 52, characterized in that the curved mirror ( 121 ) and the deflecting mirror ( 97 ) are made from one part. 54. Laser radiation source according to claim 53, characterized in that the curved mirror ( 121 ) is also designed as a deflecting mirror for the unwanted radiation. 55. Laser radiation source according to one of claims 1 to 54, characterized characterized in that the optical surfaces are non-reflective. 56. Laser radiation source according to one of claims 1 to 55, characterized characterized in that the optical components are glued into their sockets are. 57. Laser radiation source according to one of claims 1 to 55, characterized characterized in that the optical components are soldered into their sockets. 58. Laser radiation source according to one of claims 1 to 57, characterized characterized in that at least one of the optical components  a material, in particular made of sapphire, which is a higher Has thermal conductivity as glass. 59. Laser radiation source according to one of claims 26 to 58, characterized in that the means for bringing together the individual laser beams ( 37 ) are arranged within the housing ( 35 , 93 ). 60. Laser radiation source according to one of claims 14 to 59, characterized in that the sockets ( 29 ) for the end pieces ( 26 , 94 ) in the housing ( 35 , 93 ) are arranged and aligned so that the individual laser beams on the processing surface ( 81 ) can be merged. 61. Laser radiation source according to claim 60, characterized in that the means for reducing the distance between the axes of symmetry of the bundle of lenses ( 133 ) of the end pieces ( 26 , 94 ) emerging rays ( 46 , 191 , 192 , 202 , 203 ) in the housing ( 35 , 93 ) are arranged. 62. Laser radiation source according to one of claims 3 to 61, characterized in that
A cylindrical opening ( 48 ) is provided in the housing ( 36 , 93 ) for an exchangeable modulator housing ( 172 ), which can be adjusted and fixed within the cylindrical opening by twisting ( 48 ) and which has electrical connections ( 181 ) which are connected to control electronics and to a line arrangement ( 171 ) for the electrical control of the modulator and / or deflector ( 34 , 168 ), and
that the modulator housing on its inside ( 44 , 111 ) of the housing ( 35 , 93 ) facing end has a holder for the modulator and / or deflector ( 34 , 168 ) and contains the line arrangement ( 171 ) in its interior, the Line arrangement protrudes from the interior of the modulator housing ( 172 ) through the end facing the interior of the housing ( 35 , 93 ) into the interior ( 44 , 111 ) and is electrically connected to the modulator. 63. Laser radiation source according to claim 62, characterized in that the housing ( 35 , 93 ) has a plurality of cylindrical openings ( 48 ) for a plurality of modulator housings ( 172 ). 64. Laser radiation source according to one of claims 2 to 63, characterized in that the tube ( 51 , 95 , 113 ) is centered by a bore ( 47 ) arranged on the beam exit side of the housing ( 35 , 93 ) and on the housing ( 35 , 93 ) is flanged. 65. Laser radiation source according to one of claims 1 to 64, characterized in that the arrangement ( 73 , 86 ) for intercepting and rendering harmless the laser radiation, which should not cause any processing effect on the processing surface ( 81 ), on the side of the tube ( 51 , 95 , 113 ) is flanged. 66. Laser radiation source according to one of claims 1 to 64, characterized in that an arrangement ( 82 ) for removing the material removed from the processing surface ( 81 ) between the radiation exit from the transmission unit at the end of the tube ( 51 , 95 , 113 ) and Processing area ( 81 ) is provided. 67. Laser radiation source according to one of claims 2 to 67, characterized in that the tube ( 51 , 95 , 113 ) is mounted rotatably about its axis defined by the objective lens ( 61 , 103 , 112 ) and / or is displaceable in its longitudinal direction. 68. Laser radiation source according to one of claims 1 to 67, characterized characterized in that a swamp for collecting the unwanted radiation is provided, in which the unwanted radiation is directed.   69. Laser radiation source according to claim 68, characterized in that the Sump consists of a medium that absorbs the unwanted radiation, by converting the energy of the radiation into heat. 70. Laser radiation source according to claim 68 or 69, characterized in that the sump is designed as a heat exchanger. 71. Laser radiation source according to one of claims 68 to 70, characterized in that the arrangement for intercepting and rendering harmless the unwanted laser radiation between the deflection mirror ( 74 , 97 , 121 ) or the polarization-dependent mirror ( 169 ) and the sump for collecting the unwanted laser radiation contains optical component ( 75 ) which separates the interior of the tube ( 51 , 95 , 113 ) from the sump and is dimensioned in such a way that the laser radiation guided into the sump can pass straight through, while radiation emitted by the sump reflected back or scattered back, largely retained in the swamp. 72. Laser radiation source according to claim 71, characterized in that the optical component ( 75 ) is a glass plate or a lens. 73. Laser radiation source according to claim 72, characterized in that the optical component ( 75 ) is anti-reflective. 74. Laser radiation source according to one of claims 71 to 73, characterized in that the optical component ( 75 ) is glued or soldered into its socket. 75. Laser radiation source according to one of claims 50 to 54, characterized in that the arrangement ( 73 , 86 ) for intercepting the unwanted laser radiation from a cylindrically designed interception arrangement ( 73 ) with the deflecting mirror ( 74 , 97 , 121 ) - or from a cylindrical trained interception arrangement ( 86 ) or with the polarization-dependent mirror ( 169 ) - with the optical element ( 75 ), and a flange for attachment to the tube ( 51 , 95 , 113 ). 76. Laser radiation source according to one of claims 68 to 70, characterized in that the sump for collecting the unwanted radiation consists of a plate 86 which contains openings 87 through which a coolant can be passed. 77. Laser radiation source according to claim 76, characterized in that the plate ( 86 ) on the side facing the laser radiation has a flat surface which is inclined to the incident laser radiation. 78. Laser radiation source according to claim 76, characterized in that the surface of the plate is spherical or hollow. 79. Laser radiation source according to one of claims 76 to 78, characterized characterized that the surface is roughened. 80. Laser radiation source according to one of claims 1 to 79, characterized in that the optical unit ( 8 ) for shaping the laser beam is designed so that there are beam waists on the processing surface ( 81 ). 81. Laser radiation source according to one of claims 1 to 80, characterized characterized in that the optically effective surfaces of the components with anti-reflective layers are provided. 82. Laser radiation source according to one of claims 1 to 81, characterized characterized in that the optically effective surfaces compared to the Laser radiation to avoid back reflections and backscattering in the Lasers are arranged inclined. 83. Laser radiation source according to one of claims 25 to 82, characterized in that the acousto-optic modulators are arranged with respect to the incident laser radiation so that the straight, undeflected radiation (I ₀ ) causes a processing effect and that the deflected radiation (I ₁ ) has no editing effect. 84. Laser radiation source according to one of claims 25 to 82, characterized in that the acousto-optical modulators ( 34 ) are arranged with respect to the incident laser radiation in such a way that the deflected radiation (I ₁ ) produces a processing effect and that the straight-through, undeflected one Radiation (l ₀ ) has no processing effect. 85. Laser radiation source according to one of claims 1 to 84, characterized in that means are provided on the optical unit ( 8 ) for shaping the laser beam, which prevent contamination of the optical surfaces. 86. Laser radiation source according to claim 85, characterized in that the means for preventing contamination of the optical surfaces consist in that the receptacle and / or the optical unit ( 8 ) are free of outgassing materials, can be closed gas-tight, and that optical windows for Exit of the laser radiation are provided. 87. Laser radiation source according to claim 86, characterized in that the optical windows through which the laser radiation emerges are glass plates. 88. Laser radiation source according to claim 86, characterized in that the optical windows through which the laser radiation emerges, glass plates or lenses are. 89. Laser radiation source according to claim 88, characterized in that the objective lens ( 61 , 103 , 112 ) is provided as an optical window for the passage of the laser radiation, which is intended to produce a processing effect. 90. Laser radiation source according to claim 88, characterized in that the plate ( 117 ) is provided as an optical window for the passage of the laser radiation which is intended to produce a processing effect. 91. Laser radiation source according to claim 88, characterized in that the lens ( 75 ) is provided as an optical window for the passage of the laser radiation, which should not cause a processing effect. 92. Laser radiation source according to claim 86, characterized in that the parts of the receptacle for adapting the optical unit ( 8 ) ( 35 , 93 , 51 , 95 , 113 ) are connected to one another in a gastight manner and in that the assemblies ( 26 , 94 , 37 , 41 , 46 , 73 , 54 , 96 , 116 , 118 ) are gas-tight. 93. Laser radiation source according to claim 92, characterized in that seals ( 36 , 43 , 52 , 76 , 62 , 124 , 125 ) are provided as means for sealing. 94. Laser radiation source according to claim 92, characterized in that bonds ( 223 ) are provided as means for sealing. 95. Laser radiation source according to claim 92, characterized in that solderings ( 223 ) are provided as means for sealing. 96. Laser radiation source according to one of claims 1 to 95, characterized in that a valve ( 77 ) is provided on the housing ( 35 , 93 ) through which the interior of the multi-part receptacle and the optical unit ( 8 ) can be evacuated or with a protective gas is acted upon. 97. Laser radiation source according to claim 96, characterized in that the mount of the objective lens ( 61 , 103 , 112 ) has one or more openings ( 120 ) distributed over its circumference through which a protective gas can flow out ( FIG. 3f). 98. Laser radiation source according to one of claims 1 to 97, characterized in that the receptacle for adapting the optical unit ( 8 ) on the housing ( 35 , 93 ) in the region of the end pieces ( 26 , 94 ) is provided with cooling fins. 99. Laser radiation source according to one of claims 1 to 98, characterized in that the receptacle for adapting the optical unit ( 8 ) to the tube ( 118 ) in the region of the interception unit ( 73 ) and the objective lens 112 is provided with cooling fins. 100. Laser radiation source according to one of claims 1 to 99, characterized in that the optical unit ( 8 ) in the region of the end pieces and / or the lenses is provided with bores ( 87 ) for supplying a coolant ( Fig. 3d, Fig. 3e) . 101. Laser radiation source according to one of claims 1 to 100, characterized in that the modulator housing ( 172 ) is provided in the region of the modulator ( 34 ) with bores ( 87 ) for supplying a coolant.