Laser emitter arrangement and method for providing an output laser beam at an output of a laser emitter arrangement

Abstract

A laser emitter arrangement (10) for providing an output laser beam (98) at an output (12) of the laser emitter arrangement (10), comprising a base plate (16) with a flat surface portion (26), and a plurality of laser emitter devices (14) arranged on the flat surface portion (26) and fastened to the base plate (16). Each laser emitter device (14) is configured to generate a laser beam (34). The output laser beam (98) is formed from the laser beams (34) of the laser emitter devices (14).

Description

[0001] The invention relates to a laser emitter arrangement and a method for providing an output laser beam at an output of a laser emitter arrangement.

[0002] A laser emitter arrangement can provide an output laser beam, for example, for optically pumping a laser-active medium of a solid-state laser. The solid-state laser can be configured, for example, as a disk laser or fiber laser. Consequently, the output laser beam provided by the laser emitter arrangement can be suitable for optical pumping, for example, of solid-state lasers.

[0003] In addition to optical pumping, there may be other applications for the output laser beam of the laser emitter array – if the output laser beam is provided with a specific power, for example, in the processing of workpieces or in medical technology. In such applications, the output laser beam can function not only as an optical pump source, but at least be designed as an unamplified processing / treatment laser beam.

[0004] The object of the present invention is to provide a laser emitter arrangement that has improved properties, in particular is cost-effective to manufacture, and / or is suitable for providing a high-power output laser beam. Furthermore, the object of the present invention is to provide a method for providing an output laser beam at an output of a laser emitter arrangement, which has improved properties, in particular with which the high-power output laser beam can be provided at the output.

[0005] The invention solves these problems with a laser emitter arrangement having the features of claim 1 and with a method for providing an output laser beam at an output of a laser emitter arrangement having the features of claim 14. Advantageous embodiments and further developments of the invention emerge from the dependent claims.

[0006] A laser emitter arrangement according to the invention is configured to provide an output laser beam at an output of the laser emitter arrangement. The laser emitter arrangement comprises a base plate with a flat surface portion and a plurality, for example 8 to 30, in particular 10 to 25, of laser emitter devices. The plurality of laser emitter devices are arranged on the flat surface portion and fastened to the base plate. Each laser emitter device is configured to generate a laser beam. The output laser beam is formed from the laser beams of the laser emitter devices.

[0007] Advantageously, due to the arrangement of the laser emitter devices on the flat surface section, a particularly clear and simple structure of the laser emitter arrangement can be achieved. In particular, manufacturing the flat surface section can be particularly simple and cost-effective. Furthermore, due to the flat surface section, the number of components required for providing the output laser beam at the output can be reduced, so that very few components are required to implement the laser emitter arrangement. Taking into account that each component over which a laser beam is guided can reduce the power of the laser beam, power losses of the laser emitter arrangement can advantageously be kept small due to the small number of required components, which is why the laser emitter arrangement is particularly suitable for providing a high-power output laser beam.

[0008] The base plate can be cuboid-shaped. The height of the base plate can be less than the width and / or length of the base plate.

[0009] The base plate can be designed as a cooled plate for cooling the laser emitter devices. The base plate can be designed so that a cooling medium, for example cooling water, can flow through it for the purpose of cooling the laser emitter devices. However, it is also possible to cool the base plate directly or indirectly via a separate cooling plate. In the case of indirect cooling, a heat transfer layer comprising a material with a comparatively high thermal conductivity coefficient, for example a carbon material, in particular graphite, can be arranged between the base plate and the cooling plate. The cooling plate can be designed so that air can flow through or onto the cooling plate for the purpose of cooling the laser emitter devices. The heat transfer layer can have a thickness of 50 µm to 1000 µm, in particular 100 µm to 500 µm, preferably 150 µm to 250 µm, and particularly preferably 200 µm.

[0010] The base plate may be configured to be attached to an object, for example, an optical table. The base plate may have a number of elements, for example, in the form of through-holes and / or threads, for attaching the base plate to the object. The base plate may be formed from a metal material, in particular copper (Cu).

[0011] The planar surface section can be a continuous surface section. The planar surface section can be an uninterrupted surface section. The planar surface section can be arranged in a single plane of the base plate. Alternatively, the planar surface section can define a single plane of the base plate. The planar surface section can form a surface of the base plate. The surface formed by the planar surface section can be arranged in one, in particular a single, plane. The base plate can have a single planar surface section for arranging the laser emitter devices. In other words, the laser emitter devices can be arranged on a single planar surface section.

[0012] The laser emitter devices can be connected to the base plate in a form-fitting and / or material-fitting manner. For example, the laser emitter devices can be attached to the base plate by means of an adhesive bond, soldered bond, or welded bond. The adhesive bond can be created using a UV adhesive. The UV adhesive can be an adhesive that can be solidified by irradiation with ultraviolet light. Additionally or alternatively, the adhesive bond can be created using an adhesive with a thermal conductivity of over 0.5 watts / (meter*Kelvin).

[0013] The laser emitter devices can be thermally connected to the base plate such that the connection between each laser emitter device and the base plate has a thermal conductivity of at least 0.5 watts / (meter*Kelvin). In particular, the thermal conductivity of the connection between each laser emitter device and the base plate can be 0.5 watts / (meter*Kelvin) to 150 watts / (meter*Kelvin).

[0014] The laser emitter devices can be arranged at a distance from one another on the flat surface section.

[0015] Each laser beam can have a fast-axis direction and a slow-axis direction. The laser emitter devices can be arranged on the planar surface section such that the slow-axis directions of the laser beams extend, in particular are aligned, parallel to the planar surface section.

[0016] Each laser emitter device may comprise at least one emitter for generating the laser beam and a fast-axis collimator lens for collimating the laser beam in the fast-axis direction.

[0017] An emitter can be understood as a laser diode bar. Each emitter can comprise a semiconductor laser material. Each laser emitter device can comprise a single emitter. Each laser emitter device can have a chip-on-submount design.

[0018] Each emitter can extend along a longitudinal axis. Each longitudinal axis of the emitters can be aligned parallel to the base plate, in particular to the flat surface section of the base plate. The longitudinal axes of the emitters can be aligned parallel to one another. Alternatively, each longitudinal axis of the emitters can be inclined relative to the flat surface section.

[0019] The fast-axis direction and the slow-axis direction can be aligned orthogonally to each other. The laser beam emerging from the emitter can define the fast-axis direction and the slow-axis direction. The laser beam emerging from the emitter can propagate with a larger divergence angle in the fast-axis direction than in the slow-axis direction. In other words, as the laser beam emerges from the emitter, the laser beam can propagate along its propagation direction, with the diameter of the laser beam in the fast-axis direction increasing more rapidly up to the fast-axis collimator lens than the diameter of the laser beam in the slow-axis direction.

[0020] The emitter can be arranged, in particular fastened, to a holding plate of the laser emitter device. The holding plate can be arranged on the emitter, forming a planar interface that is orthogonal to the fast-axis direction. The planar interface can be aligned parallel to the planar surface portion of the base plate. The holding plate can be fastened to the base plate, in particular to the planar surface portion of the base plate.

[0021] The fast-axis collimator lens can be a cylindrical lens, in particular an aspherical cylindrical lens. The fast-axis collimator lens can be formed from quartz glass. The fast-axis collimator lens can have an anti-reflection coating for a wavelength of the laser beam of the laser emitter device. The anti-reflection coating can be suitable for reducing the reflectance of the laser beam at interfaces of the fast-axis collimator lens. The fast-axis collimator lens can be attached to the holding plate, in particular by means of an adhesive bond. The adhesive bond can be produced, for example, using a UV adhesive.

[0022] The laser emitter devices may be structurally identical. In particular, the laser emitter devices may be designed identically.

[0023] Each laser beam can have a diffraction coefficient M in the fast-axis direction 2in a range of 1 to 2 and in the slow-axis direction a diffraction index M 2 in a range of 14 to 50. The diffraction indices M 2 of the laser beams in the fast-axis direction can be equal, especially in their magnitudes. Additionally or alternatively, the diffraction indices M 2 of the laser beams in the slow-axis direction, especially in their magnitudes, must be equal.

[0024] The laser emitter arrangement can have a plurality of deflecting mirrors. Each deflecting mirror can be assigned to a laser emitter device. Each deflecting mirror can be configured to deflect the propagation direction of the laser beam of the laser emitter device assigned to the deflecting mirror by 80° to 100°, in particular 85° to 95° or 88° to 92°, preferably 90°. The deflecting mirrors can be attached to the base plate. The deflecting mirrors can be arranged on the flat surface section. The deflecting mirrors can be of identical construction.

[0025] Each deflecting mirror can have a straight edge that is inclined relative to the flat surface section. For each deflecting mirror, the straight edge with the inclined profile can define a side surface of the deflecting mirror that faces away from the base plate.

[0026] At least one deflecting mirror can be configured to deflect the laser beam of the laser emitter device associated with the deflecting mirror in such a way that the deflected laser beam is guided past the straight edge with the oblique course of another deflecting mirror.

[0027] The laser emitter assembly may include an optical device disposed between the output and the plurality of laser emitter devices. The laser beams may pass through the optical device for the purpose of changing the propagation directions of the laser beams. The optical device may be attached to the base plate. The optical device may be disposed on the flat surface portion.

[0028] The optical device can be configured to align the propagation directions of the laser beams parallel to the base plate, in particular to the flat surface section, and / or to the longitudinal axes of the emitters.

[0029] Each laser beam can impinge on the optical device at an angle of incidence other than 0° to change the propagation direction. The optical device can be wedge-shaped and / or configured as an optical wedge. The optical device can be configured to change the propagation directions of the laser beams by refracting the laser beams, for example, toward the flat surface portion of the base plate. The optical device can be configured to change the propagation directions of the laser beams, in particular only in the fast-axis direction.

[0030] For each laser beam, a distance between the laser beam and the flat surface section can depend on a propagation distance traveled by the laser beam. In other words, the distance can change depending on the propagation distance traveled by the laser beam. In particular, the distance can increase depending on the propagation distance traveled by the laser beam. Preferably, the distance can increase proportionally to the propagation distance traveled by the laser beam. The propagation distance traveled by the laser beam can be a propagation distance traveled by the laser emitter device that emits the laser beam. The output laser beam can be formed from the laser beams depending on the propagation distance traveled and / or the distance between the laser beam and the base plate.

[0031] Distance can be understood as a height, in particular the height between a laser beam and the flat surface section. The distance can be determined perpendicularly, in particular parallel to a plumb line on the flat surface section.

[0032] In the propagation direction downstream of the optical device, the distance between the laser beam and the flat surface portion from the optical device can be constant. In other words, once a laser beam has passed through the optical device, the distance between the laser beam and the flat surface portion from the optical device can be constant.

[0033] The output laser beam may be a laser beam group formed from the laser beams. Preferably, the output laser beam may consist of the laser beams. The output laser beam may propagate in a propagation direction. The propagation direction of the output laser beam may be aligned parallel to the base plate, in particular parallel to the flat surface portion of the base plate.

[0034] The output laser beam can be configured to be coupled into a waveguide for guiding the output laser beam. The waveguide can be, for example, a glass fiber or an optical fiber cable. The output laser beam can be configured to be coupled into the waveguide if an end face of the waveguide is arranged at the output. It is also conceivable that the laser emitter arrangement can have the waveguide and the output is formed by the end face of the waveguide. Alternatively, the output can be formed by an opening in a housing of the laser emitter arrangement.

[0035] The output laser beam can be formed by directing the laser beams to the output, in particular by means of optical components of the laser emitter arrangement. The optical components of the laser emitter arrangement can be arranged on the flat surface portion. The optical components of the laser emitter arrangement can be attached to the base plate.

[0036] The output laser beam can be formed by arranging the laser beams relative to one another, in particular by means of optical components of the laser emitter arrangement. Forming the output laser beam can comprise arranging the laser beams one above the other in the fast-axis direction. In a cross-section of the output laser beam, the laser beams can be arranged one above the other in the fast-axis direction, for example, at an equal distance from one another. In the cross-section of the output laser beam, the laser beams can be superimposed, in particular overlapped, at least in some regions.

[0037] The laser beams can be arranged in the cross-section of the output laser beam to form a laser beam array. The laser beam array can be aligned perpendicular to the base plate, in particular perpendicular to the flat surface portion of the base plate.

[0038] The laser beams can be arranged in the cross-section of the output laser beam such that the propagation directions of the laser beams are aligned parallel to each other. Additionally, the propagation directions of the laser beams can be offset from each other in the cross-section of the output laser beam.

[0039] The output laser beam can exit the output with a predetermined beam diameter and divergence, pass through the output, and / or be guided through the output. In other words, the output can be provided for the output laser beam to exit the laser emitter assembly.

[0040] At the output, the output laser beam can have a beam diameter in the range of, for example, 100 µm (micrometers) to 1500 µm, in particular 200 µm to 500 µm. At the output, the output laser beam can have a divergence angle in the range of, for example, 5° to 40°, in particular 10° to 25°.

[0041] The laser emitter arrangement can have a focusing device, for example in the form of a focusing lens, for focusing the output laser beam onto the output. The focusing lens can be made of quartz glass. The focusing lens can have an anti-reflection coating for a wavelength of the laser beams of the laser emitter devices. The anti-reflection coating can be suitable for reducing the reflectance of the laser beams at interfaces of the focusing lens. The focusing lens can be radially symmetrical. However, it can also have two mutually perpendicular and optionally cemented or bonded cylindrical lenses, and in particular be formed by them.

[0042] The output can be located in a focal plane of the focusing device. The focal plane can be located in the propagation direction of the laser beams after the focusing device. The output can be limited by a maximum focus diameter of the focusing device in the focal plane. The maximum focus diameter can depend on the emitter apertures.

[0043] The laser emitter arrangement can have a waveguide receptacle for a waveguide. The waveguide receptacle can be arranged at an opening of a housing of the laser emitter arrangement. The housing can have an interior space in which the laser emitter devices are arranged. A waveguide can be received by the waveguide receptacle. The waveguide can be received by the waveguide receptacle such that an end face of the waveguide is arranged at the output. The output laser beam can be formed from the laser beams and focused onto the end face of the waveguide by means of the focusing device. By focusing the output laser beam onto the end face of the waveguide, the output laser beam can be coupled into the waveguide. The end face can have an anti-reflection coating that is particularly low-reflective for a wavelength of the laser beams.

[0044] Alternatively, the output can be an opening in a housing of the laser emitter arrangement. The housing can have an interior space in which the laser emitter devices are arranged. The output laser beam can be formed from the laser beams and focused onto the opening by means of the focusing device. The output laser beam can be guided through the opening by means of the focusing device. However, the output laser beam can also pass through the opening and only then enter the focusing device if the focusing device is arranged outside the housing of the laser emitter arrangement. A sealing element that transmits the wavelength of the laser beams, for example in the form of a transparent protective glass, can be arranged in or adjacent to the opening and largely prevents unwanted foreign particles from entering the interior of the housing.

[0045] A further aspect of the invention is that by arranging the laser emitter devices on the flat surface section, the manufacture and / or assembly of the laser emitter arrangement is simplified.

[0046] In a further development of the laser emitter arrangement, each laser emitter device has a laser emitter output from which the laser beam exits the laser emitter device. Each laser emitter output is spaced a certain distance from the flat surface section. The distances, in particular all distances, of the laser emitter outputs from the flat surface section are the same. This advantageously allows the laser emitter devices to be constructed identically, thereby reducing the complexity of the laser emitter arrangement.

[0047] The laser emitter devices can be arranged on the planar surface portion such that the laser emitter outputs are arranged along a straight line. The straight line of laser emitter outputs can be aligned parallel to the planar surface portion. Alternatively, the laser emitter devices can be arranged on the planar surface portion such that the laser emitter outputs are arranged in an output plane. The output plane can be aligned parallel and offset from the planar surface portion. Each laser emitter output can be formed by the fast-axis collimator lens of the laser emitter device.

[0048] In a further development of the laser emitter arrangement, each laser emitter device is configured to emit the laser beam in a radiation direction. The radiation directions can be aligned parallel to one another. In particular, each laser emitter device can be configured to emit the laser beam in the radiation direction such that the laser beam propagates along its propagation direction, which is the same as the radiation direction. In other words, the radiation directions and the propagation directions of the laser beams can be the same.

[0049] In a further development of the laser emitter arrangement, each laser emitter device has at least one emitter. Each laser emitter device is configured to emit the laser beam in a radiation direction. Each radiation direction has an oblique course with respect to the planar surface section and / or with respect to a longitudinal axis of the emitter. Advantageously, the oblique course of the radiation direction enables a particularly simple and cost-effective formation of the output laser beam by arranging the laser beams one above the other in the fast-axis direction.

[0050] Each radiation direction and the flat surface section can define a radiation angle between them. The radiation angle between the radiation direction and the flat surface section can be other than 0°. Additionally or alternatively, each radiation direction and the longitudinal axis of the emitter can define a radiation angle between them. The radiation angle between the radiation direction and the longitudinal axis of the emitter can be other than 0°. The radiation angle between the radiation direction and the flat surface section and the radiation angle between the radiation direction and the longitudinal axis of the emitter can be the same. Each radiation angle between the radiation direction and the flat surface section and / or each radiation angle between the radiation direction and the longitudinal axis of the emitter can be 0.5° to 20°, in particular 0.5° to 10°, 1° to 5° or 2° to 4°.

[0051] The fast-axis collimator lens of each laser emitter device can be positioned relative to the emitter such that the emission direction has an oblique course relative to the flat surface section and / or relative to a longitudinal axis of the emitter. In particular, the fast-axis collimator lens of each laser emitter device can be positioned relative to the emitter such that the longitudinal axis of the emitter and an optical plane of the fast-axis collimator lens have a different course from one another. The optical plane can be aligned perpendicular to a lens plane of the fast-axis collimator lens. The optical plane can contain a center point of the fast-axis collimator lens. The optical plane of the fast-axis collimator lens can be a plane of symmetry of the fast-axis collimator lens. The optical plane can be a mirror symmetry plane of the fast-axis collimator lens.In particular, the optical plane may be the symmetry plane of the fast-axis collimator lens, which is oriented perpendicular to the lens plane of the fast-axis collimator lens. A laser beam passing through the fast-axis collimator lens may be refracted by the fast-axis collimator lens toward the optical plane.

[0052] The longitudinal axis of the emitter may not lie within the optical plane. The longitudinal axis of the emitter may intersect the optical plane at a point of intersection or be aligned parallel and offset from the optical plane. For example, the fast-axis collimator lens of each laser emitter device may be arranged relative to the emitter with a transverse offset in the fast-axis direction, in particular for the purpose of emitting the laser beam in the emission direction.

[0053] Additionally or alternatively, the fast-axis collimator lens of each laser emitter device can be tilted by a tilt angle relative to the longitudinal axis of the emitter. For each laser emitter device, the optical plane of the fast-axis collimator lens and the longitudinal axis of the emitter can define the tilt angle, which is not equal to 0°. The tilt angle can be 0.5° to 20°, in particular 0.5° to 10°, 1° to 5°, or 2° to 4°.

[0054] In a further development of the laser emitter arrangement, the plurality of laser emitter devices are arranged on the flat surface section to form at least one laser emitter row.

[0055] In a further development of the laser emitter arrangement, the laser emitter devices are arranged on the planar surface section to form a first laser emitter row and a second laser emitter row. The laser emitter devices can have a first number of laser emitter devices arranged on the planar surface section to form the first laser emitter row, and a second number of laser emitter devices arranged on the planar surface section to form the second laser emitter row.

[0056] In a further development of the laser emitter arrangement, the first laser emitter row and the second laser emitter row are aligned parallel to each other.

[0057] In a further development of the laser emitter arrangement, the first laser emitter row and the second laser emitter row are arranged offset from one another. This advantageously allows a particularly compact design of the laser emitter arrangement to be achieved. Due to the offset arrangement of the first laser emitter row and the second laser emitter row, a laser beam from a laser emitter device in the first laser emitter row can be guided between two adjacent laser emitter devices in the second row.

[0058] In a further development of the laser emitter arrangement, the output laser beam is formed by polarization coupling and / or by wavelength coupling of the laser beams of the laser emitter devices of the first laser emitter row with the laser beams of the laser emitter devices of the second laser emitter row.

[0059] For example, the laser emitter arrangement comprises a wavelength coupling device for forming the output laser beam by wavelength coupling the laser beams of the laser emitter devices of the first laser emitter row with the laser beams of the laser emitter devices of the second laser emitter row. The output laser beam can be formed by wavelength coupling the laser beams of the laser emitter devices of the first laser emitter row with the laser beams of the laser emitter devices of the second laser emitter row by means of the wavelength coupling device.

[0060] For wavelength coupling, the laser beams of the laser emitter devices of the first laser emitter row can have a different wavelength than the laser beams of the laser emitter devices of the second laser emitter row. For example, the amount of a difference formed between the wavelengths of the laser beams of the laser emitter devices of the first laser emitter row and the wavelengths of the laser beams of the laser emitter devices of the second laser emitter row can be 3 nm (nanometers) to 25 nm, in particular 5 nm to 15 nm. The wavelength coupling device can, for example, have a mirror that is transmissive for the wavelengths of the laser beams of the laser emitter devices of the second laser emitter row and reflective for the wavelengths of the laser beams of the laser emitter devices of the first laser emitter row.The output laser beam can be formed by spatially superimposing the laser beams of the laser emitter devices of the first laser emitter row with the laser beams of the laser emitter devices of the second laser emitter row by means of the mirror.

[0061] For example, the laser emitter arrangement comprises a polarization coupling device for forming the output laser beam by polarization coupling the laser beams of the laser emitter devices of the first laser emitter row with the laser beams of the laser emitter devices of the second laser emitter row. The output laser beam can be formed by polarization coupling the laser beams of the laser emitter devices of the first laser emitter row with the laser beams of the laser emitter devices of the second laser emitter row by means of the polarization coupling device.

[0062] The polarization coupling device can comprise a polarizer and a retardation plate in the form of a λ / 2 plate. The laser beams from the laser emitter devices of the first laser emitter row and the laser beams from the laser emitter devices of the second laser emitter row can be linearly polarized. The polarization of the laser beams from the laser emitter devices of the first laser emitter row and the polarization of the laser beams from the laser emitter devices of the second laser emitter row can be aligned identically before passing through the polarization coupling device. The λ / 2 plate can be arranged such that the laser beams from the laser emitter devices of the first laser emitter row pass through the λ / 2 plate. The λ / 2 plate can be configured to rotate the polarization of the laser beams from the laser emitter devices of the first laser emitter row by 90°.After passing through the λ / 2 plate, the polarization of the laser beams from the laser emitter devices of the first laser emitter row can be aligned orthogonally to the polarization of the laser beams from the laser emitter devices of the second laser emitter row. The polarizer can be configured to transmit the polarization of the laser beams from the laser emitter devices of the second laser emitter row and to reflect the polarization of the laser beams from the laser emitter devices of the first laser emitter row. The output laser beam can be formed by spatially superimposing the laser beams from the laser emitter devices of the first laser emitter row with the laser beams from the laser emitter devices of the second laser emitter row by means of the polarizer.

[0063] In a further development of the laser emitter arrangement, the output laser beam is formed such that, in particular at the output, a laser beam from the second laser emitter row is arranged at least between two adjacent laser beams from the first laser emitter row. Advantageously, the intensity profile of the output laser beam can thereby be particularly smooth. The laser beams can be directed towards the output by means of optical components of the laser emitter arrangement such that, in the cross-section of the output laser beam, in particular at the output, a laser beam from the second laser emitter row is arranged at least between two adjacent laser beams from the first laser emitter row. A laser beam from the second laser emitter row can be arranged between all adjacent laser beams from the first laser emitter row.The output laser beam can also be formed such that the laser beams of the first laser emitter row and the laser beams of the second laser emitter row are arranged alternately at the output. The output laser beam can also be formed by correspondingly overlapping laser beams of the first and second laser emitter rows.

[0064] In a further development of the laser emitter arrangement, each laser emitter device has at least one emitter. In each laser emitter device, a longitudinal axis of the emitter runs parallel to the planar surface section.

[0065] In a further development of the laser emitter arrangement, the laser emitter arrangement comprises a housing. The base plate forms a wall section of the housing. The housing can have an interior space in which the laser emitter devices are arranged. The base plate can partially form a side wall of the housing.

[0066] In a further development of the laser emitter arrangement, each laser beam travels a propagation distance from the laser emitter device generating the laser beam to the output of the laser emitter arrangement. The output laser beam is formed from the laser beams of the laser emitter devices depending on the propagation distances of the laser beams from the laser emitter devices to the output. This allows the output laser beam to be formed particularly easily.

[0067] The laser beams can have different propagation distances.

[0068] The position of a laser beam in the cross-section of the output laser beam, particularly at the output, can depend on the length of its propagation path. In other words, the length of the propagation path of a laser beam can determine its position in the cross-section of the output laser beam, particularly at the output.

[0069] In other words, an arrangement of the laser beams, in particular relative to each other, in the cross section of the output laser beam, in particular at the output, may depend on the lengths of the propagation paths.

[0070] For example, the laser beams can be emitted by the laser emitter devices obliquely with respect to the flat surface section, in particular directed away from the flat surface section, whereby a distance between a respective laser beam and the flat surface section depends on a propagation distance traveled by the laser beam. The positions of the laser beams in the cross-section of the output laser beam can depend on the distances between the laser beams and the flat surface section. In other words, the positions of the laser beams in the cross-section of the output laser beam can be determined by the distances between the laser beams and the flat surface section. As a result, the arrangement of the laser beams relative to one another in the cross-section of the output laser beam can be determined by the propagation distances traveled.

[0071] In a further development of the laser emitter arrangement, the laser emitter devices can be arranged on the flat surface section, forming a first laser emitter row and a second laser emitter row. Each radiation angle between the radiation direction of a laser emitter device of the first laser emitter row and the flat surface section can be smaller in magnitude than the radiation angle between the radiation direction of a laser emitter device of the second laser emitter row and the flat surface section. Each deflecting mirror can be assigned to a laser emitter device. The deflecting mirrors assigned to the laser emitter devices of the second laser emitter row can each be aligned orthogonally to the base plate, in particular the flat surface section.The deflecting mirrors assigned to the laser emitter devices of the first laser emitter row can each be aligned at a tilt angle to the base plate, in particular the flat surface section. The deflecting mirrors assigned to the laser emitter devices of the first laser emitter row can each be aligned at the tilt angle to that of the base plate, in particular the flat surface section, in such a way that the laser beams of the laser emitter devices of the first laser emitter row and the laser beams of the laser emitter devices of the second laser emitter row are aligned parallel to one another after deflection by the deflecting mirrors.

[0072] A method according to the invention is configured for providing an output laser beam at an output of a laser emitter arrangement. The method comprises the steps of: arranging a plurality, for example 10 to 25, of laser emitter devices of the laser emitter arrangement on a flat surface portion of a base plate of the laser emitter arrangement; attaching the laser emitter devices to the base plate; generating laser beams by means of a plurality of laser emitter devices; and forming the output laser beam from the laser beams of the laser emitter devices. The method can be configured to operate a previously described laser emitter arrangement.

[0073] Further advantages and advantageous embodiments of the invention can be found in the figures, their description, and the claims. All features disclosed in the figures, their description, and the claims may be essential to the invention both individually and in any combination.

[0074] They show: Fig. 1 a schematic plan view of a laser emitter arrangement, Fig. 2 a schematic oblique view of the laser emitter arrangement of Fig. 1, Fig. 3 shows a further schematic oblique view of the laser emitter arrangement of Fig. 1, Fig. 4 a schematic oblique view of a laser emitter device of the laser emitter arrangement of Fig. 1 without fast-axis collimator lens, Fig. 5 a schematic side view of the laser emitter device of Fig. 4 with fast-axis collimator lens, Fig. 6 a schematic representation of a deflection mirror of the laser emitter arrangement of Fig. 1, Fig. 7 a schematic oblique view of the deflection mirror of Fig. 6, Fig. 8 a schematic representation of an optical device of the laser emitter arrangement of Fig. 1, Fig. 9 is a schematic representation of a cross-section of a laser emitter arrangement of Fig. 1 provided output laser beam, Fig. 10 a schematic representation of another embodiment of a laser emitter arrangement, Fig. 11 a schematic plan view of another embodiment of a laser emitter arrangement, Fig. 12 a schematic plan view of another embodiment of a laser emitter arrangement, Fig. 13 a schematic oblique view of the laser emitter arrangement of Fig. 12, Fig. 14 is another schematic oblique view of the laser emitter arrangement of Fig. 12, Fig. 15 a schematic representation of a section of a cross-section of a device provided with the laser emitter arrangement of Fig. 12 provided output laser beam, Fig. 16 a schematic plan view of another embodiment of a laser emitter arrangement, Fig. 17 a schematic oblique view of the laser emitter arrangement of Fig. 16, Fig. 18 is another schematic oblique view of the laser emitter arrangement of Fig. 16, Fig. 19 a schematic oblique view of an area XIX according to Fig. 17, Fig. 20 a further schematic oblique view of the area XIX according to Fig. 17, and Fig. 21 a schematic representation of a coupling element of the laser emitter arrangement of Fig. 16.

[0075] Fig. 1 to 3 show a laser emitter arrangement 10. The laser emitter arrangement 10 is configured to provide an output laser beam at an output 12 of the laser emitter arrangement 10.

[0076] The laser emitter arrangement 10 has a plurality of identical laser emitter devices 14 and a base plate 16.

[0077] The base plate 16 is cuboid-shaped. The height 18 of the base plate is smaller than the width 20 and the length 22 of the base plate 16.

[0078] The base plate 16 is designed to be attached to an object, for example, to an optical table and / or a housing part of an enclosing housing for the laser emitter arrangement 10. The base plate 16 has a number of through-holes 24 for attaching the base plate 16 to the object. For example, the base plate 16 can be attached to the object by means of a screw connection, wherein the screws of the screw connection are guided through the through-holes 24. In the illustrated embodiment, the base plate 16 has six through-holes 24. However, a base plate with a fewer or higher number of through-holes 24 is also conceivable.

[0079] The base plate 16 has a flat surface section 26. The flat surface section 26 is a continuous and uninterrupted surface section. The flat surface section 26 forms a single plane of the base plate 16. The flat surface section 26 is a surface of the base plate 16.

[0080] The laser emitter devices 14 are arranged on the flat surface section 26 and fastened to the base plate 16. In the illustrated embodiment, the laser emitter arrangement 10 has a total of 11 laser emitter devices 14. However, a laser emitter arrangement with a smaller or larger number of laser emitter devices is also conceivable. In embodiments not specifically illustrated, for example, only eight laser emitter devices 14 or up to 32 laser emitter devices 14 are present.

[0081] Each laser emitter device 14 has an emitter 28 made of a semiconductor laser material and a fast-axis collimator lens 30. In Fig. 4 shows a single laser emitter device 14 of the laser emitter arrangement 10 without the fast-axis collimator lens 30.

[0082] Fig. 4 shows that the laser emitter device 14 has a single emitter 28. The emitter 28 extends along a longitudinal axis 32. The emitter 28 is configured to generate a laser beam 34. Thus, the laser emitter device 14 is configured to generate the laser beam 34. The longitudinal axis 32 of the emitter 28 is aligned parallel to the planar surface portion 26.

[0083] In the illustrated embodiment of the Fig. 4, the emitter 28 emits the laser beam 34. The laser beam 34 propagates along its propagation direction 36. The propagation direction 36 and the longitudinal axis 32 of the emitter 28 are aligned parallel to each other. In particular, the propagation direction 36 and the longitudinal axis 32 of the emitter 28 can have the same course.

[0084] The laser beam 34 exiting the emitter 28 defines a fast-axis direction 38 and a slow-axis direction 40 that are orthogonal to each other. As the laser beam 34 exits the emitter 28, the laser beam 34 propagates along its propagation direction 36, with a diameter 42 of the laser beam 34 increasing more sharply in the fast-axis direction 38 than a diameter 44 of the laser beam 34 in the slow-axis direction 40. Consequently, the laser beam 34 has an elliptical cross-section after exiting the emitter 28.

[0085] The emitter 28 is arranged on and held by a holding plate 46 of the laser emitter device 14. The holding plate 46 contacts the emitter 28 at a planar interface that is orthogonal to the fast-axis direction 38. The planar interface is aligned parallel to the planar surface portion 26.

[0086] Fig. 5 shows the laser emitter device 14 of Fig. 4 with the fast-axis collimator lens 30. The laser emitter device 14 is attached to the base plate 16. The laser emitter device 14 is attached to the base plate 16 by means of a connection between the base plate 16 and the holding plate 46. In this case, the connection is, for example, a soldered connection.

[0087] The solder joint has a thermal conductivity of at least 35 watts / (meter*Kelvin). Heat generated in the emitter 28 during the generation of the laser beam 34 is dissipated from the emitter 28 by means of the holding plate 46 and the base plate 16.

[0088] The fast-axis collimator lens 30 is configured to collimate the laser beam 34 in the fast-axis direction 38. In other words, the laser beam 34 emitted by the laser emitter device 14 is collimated in the fast-axis direction 38.

[0089] The fast-axis collimator lens 30 is an aspherical cylindrical lens made of quartz glass, in this case quartz glass with a particularly high refractive index. The fast-axis collimator lens 30 has an anti-reflective coating that reduces the proportion of reflected light to a relative minimum for a wavelength of the laser beam 34. The anti-reflective coating reduces the degree of reflection of the laser beam 34 at the interfaces of the fast-axis collimator lens 30.

[0090] Fig. Figure 5 shows that the fast-axis collimator lens 30 is attached to the holding plate 46, in this example, by means of an adhesive bond. The adhesive bond is made using a UV adhesive. The UV adhesive is an adhesive that can be solidified by irradiation with ultraviolet light.

[0091] The fast-axis collimator lens 30 is positioned relative to the emitter 28 such that an emission direction 48, in which the laser emitter device 14 emits the laser beam 34, has an oblique course with respect to the longitudinal axis 32 of the emitter 28. In other words, by positioning the fast-axis collimator lens 30 relative to the emitter 28, the laser emitter device 14 is configured to emit the laser beam 34 in the emission direction 48 oriented obliquely to the longitudinal axis 32 of the emitter 28. Due to the oblique orientation of the emission direction 48, the emission direction 48 does not run parallel to the longitudinal axis 32 of the emitter 28.

[0092] The fast-axis collimator lens 30 can define a lens plane 50 and an optical plane 52. The lens plane 50 is the plane in which the fast-axis collimator lens 30 is arranged. A focal point of the fast-axis collimator lens 30 is spaced from the lens plane 50 by a focal length of the fast-axis collimator lens 30.

[0093] The optical plane 52 of the fast-axis collimator lens 30 is oriented perpendicular to the lens plane 50. The optical plane 52 of the fast-axis collimator lens 30 is a mirror symmetry plane of the fast-axis collimator lens 30. A laser beam passing through the fast-axis collimator lens 30 is refracted by the fast-axis collimator lens 30 toward the optical plane 52.

[0094] The optical plane 52 intersects the lens plane 50 in a central axis 54 of the fast-axis collimator lens 30.

[0095] The fast-axis collimator lens 30 is positioned relative to the emitter 28 such that the longitudinal axis 32 of the emitter 28 and the optical plane 52 of the fast-axis collimator lens 30 have a different course from one another for the purpose of emitting the laser beam 34 in the emission direction 28. In other words, the fast-axis collimator lens 30 is arranged such that the longitudinal axis 32 of the emitter 28 does not lie within the optical plane 52.

[0096] The fast-axis collimator lens 30 is arranged with a transverse offset 56 in the fast-axis direction 38 relative to the emitter 28. The transverse offset 56 is a distance between the longitudinal axis 32 of the emitter 28 and the central axis 54 of the fast-axis collimator lens 30. A distance between the longitudinal axis 32 of the emitter 28 and the flat surface portion 26 is smaller than a distance between the central axis 54 of the fast-axis collimator lens 30 and the flat surface portion 26.

[0097] In addition, the fast-axis collimator lens 30 is tilted by a tilt angle 58 relative to the longitudinal axis 32 of the emitter 28. The optical plane 52 of the fast-axis collimator lens 30 and the longitudinal axis 32 of the emitter 28 define the tilt angle 58 between them. In the illustrated initial example, the tilt angle 58 is 3°.

[0098] Due to the transverse offset 56 and the tilt angle 58, the laser beam 34 generated by the emitter 28 is deflected by the fast-axis collimator lens 30 in the fast-axis direction 38 away from the flat surface section 26. Due to the transverse offset 56 and the tilt angle 58 of the fast-axis collimator lens 30, the laser emitter device 14 is configured to emit the laser beam 34 in the emission direction 48 oriented obliquely to the flat surface section 26.

[0099] The radiation direction 48 and the flat surface section 26 define a radiation angle 60 between them. In the illustrated initial example, the radiation angle 60 is 4°.

[0100] The radiation direction 48 is directed away from the flat surface section 26. The radiation direction 48 can be broken down into a directional component parallel to the flat surface section 26 and a directional component perpendicular to the flat surface section 26. The directional component perpendicular to the flat surface section 26 is directed away from the flat surface section 26.

[0101] The laser beam 34 leaves the laser emitter device 14 by exiting the fast-axis collimator lens 30. The laser beam 34 exits the laser emitter device 14 at an exit region of the fast-axis collimator lens 30. The exit region of the fast-axis collimator lens 30 forms a laser emitter output 62 of the laser emitter device 14.

[0102] The propagation direction 36 of the laser beam 34 after exiting the laser emitter device 14 is identical to the emission direction 48 in which the laser emitter device 14 emits the laser beam 34. In other words, after the laser beam exits the laser emitter device 14, the laser beam 34 propagates along its propagation direction 36, which has an oblique course relative to the flat surface section 26.

[0103] Due to the oblique emission of the laser beam 34 in the emission direction 48 from the laser emitter device 14, a distance 64 between the laser beam 34 and the flat surface section 26 depends on a propagation distance of the laser beam 34. A propagation distance can be understood as a distance that the laser beam travels by propagating in the propagation direction.

[0104] The distance 64 is determined in a direction parallel to a normal on the flat surface section 26 from the laser beam 34. The distance 64 can also be understood as a height at which the laser beam 34 is spaced from the flat surface section 26. Since the laser beam 34 is emitted by the laser emitter device 14 away from the flat surface section 26, the distance 64 increases with increasing propagation distance of the laser beam 34 from the laser emitter device 14.

[0105] Fig. 1 shows that the laser emitter devices 14 are arranged on the flat surface section 26 such that the slow-axis directions 40 of the laser beams 34 are aligned parallel to the flat surface section 26. The emission directions 48 are aligned parallel to one another. The propagation directions 36 are aligned parallel to one another. The longitudinal axes 32 of the emitters 28 are aligned parallel to one another.

[0106] Each laser emitter output 62 of the laser emitter devices 14, from which the laser beam 34 emerges, is spaced a certain distance from the flat surface section 26. The distances of the laser emitter outputs 62 of the laser emitter device 14 from the flat surface section 26 are equal in magnitude.

[0107] The laser emitter devices 14 are arranged on the flat surface section 26 such that the laser emitter outputs 62 are arranged along a straight line. The straight line of the laser emitter outputs 62 is aligned parallel to the flat surface section 26.

[0108] The laser emitter devices 14 are arranged on the flat surface section 26 to form a laser emitter row 66. A direction 68 of the laser emitter row 66 runs parallel to the flat surface section 26. Two adjacent laser emitter devices 14 are arranged at a distance 70 from one another on the flat surface section 26. The distances 70 between the laser emitter devices 14 are equal.

[0109] In the propagation direction 36, downstream of the laser emitter devices 14, a plurality of slow-axis collimator lenses 72 of the laser emitter arrangement 10 are arranged on the flat surface section 26. The slow-axis collimator lenses 72 are of identical design. Overall, the laser emitter arrangement 10 has 11 slow-axis collimator lenses 72. The number of slow-axis collimator lenses 11 corresponds in this case to the number of laser emitter devices 14. Therefore, if fewer or more laser emitter devices 14 are present in embodiments not specifically illustrated, the number of slow-axis collimator lenses 11 is also changed accordingly.

[0110] Accordingly, in the present case, each slow-axis collimator lens 72 is assigned to a laser emitter device 14 of the laser emitter arrangement 10. Thus, the number of slow-axis collimator lenses 72 is equal to the number of laser emitter devices 14.

[0111] Each slow-axis collimator lens 72 is configured to collimate the laser beam 34 in the slow-axis direction 40. In other words, each laser beam 34 that passes through the slow-axis collimator lens 72 is collimated in the slow-axis direction 40.

[0112] Each slow-axis collimator lens 72 is an aspherical cylindrical lens made of fused silica. The slow-axis collimator lens 72 has an anti-reflective coating for a wavelength of the laser beam 34, i.e., to reduce a proportion of reflected light from the laser beam 34 at the slow-axis collimator lens 72 to a relative minimum.

[0113] Each slow-axis collimator lens 72 is attached to the base plate 16, as shown in the example, by means of an adhesive bond. The adhesive bond is made using a UV adhesive.

[0114] The slow-axis collimator lenses 72 are arranged on the flat surface section 26 to form a slow-axis collimator lens array 74. A direction 76 of the slow-axis collimator lens array 74 runs parallel to the flat surface section 26. The direction 76 of the slow-axis collimator lens array 74 runs parallel to the direction 68 of the laser emitter array 66.

[0115] In the propagation direction 36, downstream of the slow-axis collimator lenses 72, a plurality of deflection mirrors 78 of the laser emitter arrangement 10 are arranged on the flat surface section 26. The deflection mirrors 78 are of identical design. In total, the laser emitter arrangement 10 has 11 deflection mirrors 78.

[0116] Each deflecting mirror 78 is assigned to a laser emitter device 14 of the laser emitter arrangement 10. Thus, the number of deflecting mirrors 78 is equal to the number of laser emitter devices 14.

[0117] Each deflecting mirror 78 is attached to the base plate 16 by means of an adhesive bond. The adhesive bond is made using a UV adhesive.

[0118] Each deflecting mirror 78 is configured to deflect the propagation direction 36 of the laser beam 34 of the laser emitter device 14 associated with the deflecting mirror 78 by 90°. In other words, each laser beam 34 strikes the deflecting mirror 78 at an angle of incidence of 45°. Deflecting the laser beam 34 by means of the deflecting mirror 78 changes the propagation direction 36 of the laser beam 34.

[0119] Fig. 6 shows a deflection mirror 78 of the laser emitter arrangement 10 and the base plate 16. Fig. 7 shows the deflection mirror 78 of Fig. 6 without the base plate 16.

[0120] The deflecting mirror 78 has a mirror surface 80. The mirror surface 80 is aligned perpendicular to the flat surface section 26.

[0121] The mirror surface 80 is configured to deflect the propagation direction 36 of the laser beam 34 of the laser emitter device 14 associated with the deflection mirror 78. In particular, the mirror surface 80 is configured to reflect the laser beam 34 of the laser emitter device 14 associated with the deflection mirror 78.

[0122] The mirror surface 80 is formed from alternating, thin layers of different refractive indices. In other words, the deflecting mirror 78 is a Bragg mirror.

[0123] The deflecting mirror 78 has a straight edge 82 that is inclined relative to the flat surface section 26. In other words, the straight edge 82 is oriented obliquely relative to the flat surface section 26. The obliquely oriented straight edge 82 is formed without curvature and extends along a straight line.

[0124] The obliquely aligned straight edge 82 forms a corner of the deflecting mirror 78. The obliquely aligned straight edge 82 delimits the mirror surface 80. The obliquely aligned straight edge 82 delimits a side surface 84 of the deflecting mirror 78, which faces away from the flat surface section 26. The side surface 84 is oriented perpendicular to the mirror surface 80. The obliquely aligned straight edge 82 is a boundary between the mirror surface 80 and the side surface 84 facing away from the flat surface section 26. In other words, the obliquely aligned straight edge 82 is arranged between the mirror surface 80 and the side surface 84 facing away from the flat surface section 26.

[0125] The deflecting mirror 78 has a further side surface 86. The further side surface 86 is arranged opposite the side surface 84. The further side surface 86 faces the flat surface section 26. The side surface 84 and the further side surface 86 are oriented opposite one another.

[0126] The oblique course of the straight edge 82 and the flat surface section 26 define an angle 88 between them. The angle 88 between the obliquely running straight edge 82 and the flat surface section 26 satisfies the condition α'=atan(tan α2), where α is the beam angle 60 and α' is the angle 88.

[0127] Fig. 1 shows that the deflecting mirrors 78 are arranged on the flat surface section 26 to form a deflecting mirror row 90. A direction 92 of the deflecting mirror row 90 runs parallel to the flat surface section 26. The direction 92 of the deflecting mirror row 90 runs parallel to the direction 68 of the laser emitter row 66. The direction 92 of the deflecting mirror row 90 runs parallel to the direction 76 of the slow-axis collimator lens row 74.

[0128] Each deflecting mirror 78, except for the deflecting mirror 78 arranged closest to the output 12, deflects the respective laser beam 34 such that the deflected laser beam 34 is guided past the straight edge 82 with the oblique path of another deflecting mirror 78. The other deflecting mirror 78 is arranged between the laser beam 34 deflected by the deflecting mirror 78 and the flat surface section 26.

[0129] The oblique emission of the laser beams 34 enables the use of identically designed deflecting mirrors 78. The deflecting mirrors 78 are spaced apart from one another in the direction 92 of the deflecting mirror row 90 in such a way that the distances 64 between the laser beams 34 and the flat surface section 26 increase for a propagation distance which is equal to a distance between two adjacent deflecting mirrors 78 in such a way that the laser beams 34 are guided past the deflecting mirrors 78 without grazing them.

[0130] Each deflection mirror 78 is spaced a distance 94 from the laser emitter device 14 associated with the deflection mirror 78. The distances 94 between each deflection mirror 78 and the laser emitter device 14 associated with the deflection mirror 78 are equal.

[0131] Each deflection mirror 78 is spaced a distance 96 from the output 12. The distances 96 differ from one another. As a result, each laser beam 34 travels a different propagation distance from the laser emitter device 14 to the output 12. As a result, the distances 64 between the laser beams 34 and the flat surface section 26 at the output 12 differ from one another.

[0132] The propagation directions 36 of the laser beams 34 are aligned parallel to one another after deflection by the deflection mirrors 78. After deflection by the deflection mirrors 78, the laser beams 34 are arranged one above the other in the fast-axis direction 38. The deflection mirrors 78 are configured to arrange the laser beams 34 one above the other such that the laser beams 34 are spaced apart by an equal distance.

[0133] The output laser beam 98 is formed by arranging the individual laser beams 34 relative to one another using the deflection mirrors 78. The output laser beam 98 is a laser beam group formed from the laser beams 34. Forming the output laser beam 98 involves arranging the laser beams 34 one above the other in the fast-axis direction 38 using the deflection mirrors 78.

[0134] The output laser beam 98 propagates in a propagation direction. In other words, the formed laser beam group propagates in a propagation direction resulting from the individual propagation directions 36 of the laser beams 34. Since the propagation directions 36 of the laser beams 34 are aligned parallel to one another after deflection by the deflection mirrors, the propagation direction of the output laser beam 98 is aligned parallel to all propagation directions 36 of the laser beams 34.

[0135] In the propagation direction 36, downstream of the deflecting mirrors 78, an optical device 100 of the laser emitter arrangement 10 is arranged on the flat surface section 26. The optical device 100 is arranged in a beam path of the laser beams 34 between the output 12 and the deflecting mirrors 78.

[0136] The optical device 100 is formed as a one-piece optical component of the laser emitter arrangement 10. The optical device 100 is formed as a standalone optical component of the laser emitter arrangement 10. In other words, the optical device 100 is formed separately from the remaining optical components of the laser emitter arrangement 10.

[0137] The optical device 100 is attached to the base plate 16 by means of an adhesive bond. The adhesive bond is made using a UV adhesive.

[0138] The laser beams 34 pass through the optical device 100 for the purpose of changing the propagation directions 36. The optical device 100 is transparent to a wavelength of the laser beams 34.

[0139] Fig. 8 shows the optical device 100 of the laser emitter arrangement 10 and the base plate 16. The optical device 100 is designed as an optical wedge made of quartz glass.

[0140] The optical device 100 has a flat entrance surface 102 and a flat exit surface 104. The flat entrance surface 102 and the flat exit surface 104 extend obliquely to each other.

[0141] The laser beams 34 strike the flat entrance surface 102 of the optical device 100, pass through the optical device 100 and exit the optical device 100 from the flat exit surface 104.

[0142] Each laser beam 34 strikes the flat entrance surface 102 at an angle of incidence 106. The angle of incidence 106 is defined by a normal to the flat entrance surface 102 and the propagation direction 36 of the laser beam 34. All angles of incidence 106 are equal.

[0143] The flat entrance surface 102 and the flat exit surface 104 each form a phase boundary for the laser beams 34. The optical device 100 is configured to change each propagation direction 36 of the laser beams 34 in the fast-axis direction by refraction at the flat entrance surface 102 and at the flat exit surface 104. In other words, the optical device 100 is configured to change the propagation directions 36 of the laser beams 34 in the direction of the flat surface section 26 by refraction at the flat entrance surface 102 and at the flat exit surface 104. As a result, the laser beams 34 are deflected in the direction of the flat surface section 26 by means of the optical device 100.

[0144] The optical device 100 is configured to change each propagation direction 36 of the laser beams 34 by a deflection angle 108. Each deflection angle 108 is defined between the propagation direction 36 of the laser beam 34 before passing through the optical device 100 and the propagation direction 36 of the laser beam 34 after passing through the optical device 100. Each deflection angle 108 of the laser beams 34 and the emission angle 60 of the laser beams 34 are equal.

[0145] After passing through the optical device 100, the propagation direction of the output laser beam 98 is aligned parallel to the flat surface section 26. Each laser beam 34 propagates parallel to the flat surface section 26 after passing through the optical device 100. In other words, after passing through the optical device 100, the propagation directions 36 of the laser beams 34 are aligned parallel to the flat surface section 26. The optical device 100 thus compensates for the oblique emission directions 48.

[0146] In the propagation direction 36 downstream of the optical device 100, each distance 64 between the laser beam 34 and the flat surface section 26 is constant. In other words, once a laser beam 34 has passed through the optical device 100, the distance 64 between the laser beam 34 and the flat surface section 26 no longer changes depending on the propagation distance of the laser beam 34.

[0147] A focusing device 110 of the laser emitter arrangement 10 is arranged on the flat surface section 26 downstream of the optical device 100 in the propagation direction 36. The focusing device 110 is attached to the base plate 16 by means of an adhesive bond. The adhesive bond is produced using a UV adhesive.

[0148] The focusing device 110 is configured to focus the output laser beam 98 onto the output 12. The focusing device 110 is designed as a focusing lens made of quartz glass. The focusing device 110 has an anti-reflective coating for a wavelength of the laser beams 34 of the laser emitter devices 14. The anti-reflective coating reduces the degree of reflection of the laser beam 34 at the interfaces of the focusing device 110.

[0149] The focusing device 110 is arranged on the flat surface section 26 in such a way that the output 12 lies in a focal plane of the focusing device 110 after the focusing device 110 in the propagation direction of the output laser beam 98.

[0150] The focusing device 110 focuses the output laser beam 98 onto the output 12 such that the output laser beam 98 has a predetermined beam diameter and a predetermined divergence at the output 12. In other words, the output laser beam 98 exits the output with the predetermined beam diameter and the predetermined divergence. In the illustrated output example, the predetermined beam diameter is 400 µm and the predetermined divergence is 40°.

[0151] Fig. Figure 9 schematically shows a cross-section of the output laser beam 98 in the output 12. A beam profile of the output laser beam 98 is formed by the laser beams 34 arranged one above the other in the fast-axis direction 38. The laser beams 34 are arranged relative to one another in the cross-section to form a laser beam row 112. One direction 114 of the laser beam row 112 is oriented perpendicular to the flat surface section 26.

[0152] The laser beams 34 are arranged one above the other at an equal distance 116 in the fast-axis direction 38. Each distance 116 between two adjacent laser beams 43 depends on the propagation distances of the two adjacent laser beams 43 from the laser emitter devices 14 emitting the two adjacent laser beams 43 to the optical device 100.

[0153] For example, the distance 116 between the two adjacent laser beams 43 changes when the propagation path of one of the two adjacent laser beams 43 between the laser emitter device 14 emitting the laser beam 43 to the optical device 100 is lengthened or shortened. The dependence of the output laser beam 98 on the propagation paths is achieved by the oblique course of the propagation directions 36 of the laser beams 34 with respect to the flat surface section 26.

[0154] Thus, the positions of the laser beams 34 in the cross-section of the output laser beam 98 are determined by the propagation distances from the laser emitter devices 14 to the output 12. In other words, the output laser beam 98 is formed as a function of the propagation distances from the laser emitter devices 14 to the output 12. The dependence on the propagation distances is a dependence on the lengths of the propagation distances.

[0155] The lengths of the propagation paths of the laser beams 34 depend on an arrangement of the laser emitter devices 14 on the flat surface section 26. As a result, the output laser beam 98 is formed from the laser beams 34 depending on the positions of the laser emitter devices 14 on the flat surface section 26.

[0156] In the illustrated embodiment, the laser emitter arrangement 10 has a housing (not shown). The base plate 16 forms a side wall of the housing. The housing has an interior in which the laser emitter devices 14, the slow-axis collimator lenses 72, the deflecting mirrors 78, the optical device 100, and the focusing device 110 are arranged. The output 12 is formed by an opening in the housing. The output laser beam 98 is focused onto the opening by means of the focusing device 110. The output laser beam 98 passes through the opening and exits the housing.

[0157] In Fig. 10 shows a further embodiment of a laser emitter arrangement 10, wherein identical and functionally equivalent elements are given the same reference numerals and in this respect reference is made to the above explanations regarding the embodiment of the Fig. 1 to 9, so that essentially only the existing differences are discussed.

[0158] The laser emitter arrangement 10 of the Fig. 10 has a waveguide receptacle (not shown) for receiving a waveguide 118 in the form of an optical fiber cable for guiding the output laser beam 98. The receptacle is arranged at an opening in the housing of the laser emitter arrangement 10. The waveguide 118 is received by the receptacle. The waveguide 118 is received by the receptacle such that an end face 120 of the waveguide 118 is arranged at the output 12. The output laser beam 98 is focused onto the output 12 by means of the focusing device 110 such that the output laser beam 98 is coupled into the waveguide 118. The output laser beam 98 is thus designed to be coupled into the waveguide 118 if the end face 120 of the waveguide 118 is arranged, in particular placed, at the output 12.

[0159] In Fig. 11 shows a further embodiment of a laser emitter arrangement 10, wherein identical and functionally equivalent elements are given the same reference numerals and in this respect reference is made to the above explanations regarding the embodiments of the Fig. 1 to 10, so that essentially only the existing differences are discussed.

[0160] The laser emitter devices 14 are arranged on the flat surface portion 26 of the base plate 16, forming a first laser emitter row 122 and a second laser emitter row 124. Each laser emitter row 122, 124 is formed from nine laser emitter devices 14.

[0161] The first laser emitter row 122 extends in a direction 126. The direction 126 of the first laser emitter row 122 runs parallel to the flat surface section 26. The second laser emitter row 124 extends in a direction 128. The direction 128 of the second laser emitter row 124 runs parallel to the flat surface section 26. The direction 126 of the first laser emitter row 122 is aligned parallel to the direction 128 of the second laser emitter row 124.

[0162] The first laser emitter row 122 and the second laser emitter row 124 are aligned offset from one another. The first laser emitter row 122 and the second laser emitter row 124 are aligned offset from one another such that, between two adjacent laser emitter devices of the second laser emitter row 124, a laser beam 34 from a laser emitter device 14 of the first laser emitter row 122 is guided past the two adjacent laser emitter devices 14 of the second laser emitter row 124. As a result, the laser beams 34 are arranged relative to one another in the cross-section of the output laser beam 98 at the output 12 such that, between two adjacent laser beams 34 of the laser emitter device 14 of the first laser emitter row 122, a laser beam 34 from the laser emitter device 14 of the second laser emitter row 124 is arranged.

[0163] The slow-axis collimator lenses 72 are arranged on the flat surface section 26 to form a first slow-axis collimator lens row 130 and a second slow-axis collimator lens row 132. The slow-axis collimator lenses 72 of the first slow-axis collimator lens row 130 are assigned to the laser emitter devices 14 of the first laser emitter row 122. The slow-axis collimator lenses 72 of the second slow-axis collimator lens row 132 are assigned to the laser emitter devices 14 of the second laser emitter row 124.

[0164] Each laser emitter device 14 of the first laser emitter row 122 is spaced apart by a distance 134 from the deflection mirror 78 associated with the laser emitter device 14. Each laser emitter device 14 of the second laser emitter row 124 is spaced apart by a distance 136 from the deflection mirror 78 associated with the laser emitter device 14.

[0165] The distance 134 between the laser emitter devices 14 of the first laser emitter row 122 and the deflecting mirrors 78 is greater than the distance 136 between the laser emitter devices 14 of the second laser emitter row 124 and the deflecting mirrors 78.

[0166] The radiation angles 60 between the radiation directions 48 of the laser emitter devices 14 of the first laser emitter row 122 and the flat surface section 26 are smaller in their magnitudes than the magnitudes of the radiation angles 60 between the radiation directions 48 of the laser emitter devices 14 of the second laser emitter row 124 and the flat surface section 26.

[0167] The deflecting mirrors 78, which are assigned to the laser emitter devices 14 of the second laser emitter row 122, are each aligned orthogonally to the flat surface section 26.

[0168] The deflecting mirrors 78, which are assigned to the laser emitter devices 14 of the first laser emitter row 122, are each aligned at a tilt angle to the flat surface section 26. In the illustrated embodiment, the deflecting mirrors 78, which are assigned to the laser emitter devices 14 of the first laser emitter row 122, are each aligned at the tilt angle to the flat surface section 26 such that the laser beams 34 of the laser emitter devices 14 of the first laser emitter row 122 and the laser beams 34 of the laser emitter devices 14 of the second laser emitter row 124 are aligned parallel to one another after deflection by the deflecting mirrors 78.

[0169] In the initial example of the Fig. 11, the focusing device 110 has a first cylindrical lens 138 and a second cylindrical lens 140. The first cylindrical lens 138 and the second cylindrical lens 140 are configured to focus the output laser beam 98 onto the output 12.

[0170] The first cylindrical lens 138 and the second cylindrical lens 140 are each an aspherical cylindrical lens made of quartz glass with a comparatively high refractive index. The first cylindrical lens 138 and the second cylindrical lens 140 each have an anti-reflective coating for a wavelength of the laser beams 34. In embodiments not specifically shown, the cylindrical lenses 140 are spherical.

[0171] The first cylindrical lens 138 is configured to focus the output laser beam 98 in the fast-axis direction 38 onto the output 12. The second cylindrical lens 140 is configured to focus the output laser beam 98 in the slow-axis direction 40 onto the output 12.

[0172] In Fig. 12 to 14, a further embodiment of a laser emitter arrangement 10 is shown, wherein identical and functionally equivalent elements are given the same reference numerals and in this respect reference is made to the above explanations regarding the embodiments of the Fig. 1 to 11, so that essentially only the existing differences are discussed.

[0173] Each laser emitter row 122, 124 is formed from 13 laser emitter devices 14.

[0174] The deflecting mirrors 78 are arranged on the flat surface section 26 to form a first deflecting mirror row 142 and a second deflecting mirror row 144.

[0175] The first deflecting mirror row 142 extends in a direction 146. The direction 146 of the first deflecting mirror row 142 runs parallel to the flat surface section 26. The second deflecting mirror row 144 extends in a direction 148. The direction 148 of the second deflecting mirror row 144 runs parallel to the flat surface section 26. The direction 146 of the first deflecting mirror row 142 is aligned parallel to the direction 148 of the second deflecting mirror row 144.

[0176] The first deflection mirror row 142 is assigned to the laser emitter device 14 of the first laser emitter row 122. The second deflection mirror row 144 is assigned to the laser emitter devices 14 of the second laser emitter row 124.

[0177] The first deflection mirror row 142 and the second deflection mirror row 144 are arranged offset from one another on the flat surface section 26. The first deflection mirror row 142 and the second deflection mirror row 144 are arranged offset from one another such that a laser beam 34 of a laser emitter device 14 of the second laser emitter row 124 is guided between two adjacent deflection mirrors 78 of the first deflection mirror row 142.

[0178] By means of the first deflection mirror row 142, the laser beams 34 of the laser emitter devices 14 of the first laser emitter row 122 are arranged one above the other in the fast-axis direction 38. The laser beams 34 of the laser emitter devices 14 of the first laser emitter row 122 arranged one above the other in the fast-axis direction 38 form a first laser beam group 150. The first laser beam group 150 is in Fig. 12 is shown with a dashed arrow.

[0179] By means of the second deflection mirror row 144, the laser beams 34 of the laser emitter devices 14 of the second laser emitter row 124 are arranged one above the other in the fast-axis direction 38. The laser beams 34 of the laser emitter devices 14 of the second laser emitter row 124 arranged one above the other in the fast-axis direction 38 form a second laser beam group 152. The second laser beam group 152 is in Fig. 12 is shown with a dashed arrow.

[0180] The two laser beam groups 150, 152 propagate parallel and offset from each other. The two laser beam groups 150, 152 pass through the optical device 100 at different locations.

[0181] The laser emitter arrangement 10 has a polarization coupling device 154. The output laser beam 98 is formed by polarization coupling of the two laser beam groups 150, 152. The output laser beam 98 is in Fig. 12 is shown with a dashed arrow.

[0182] The polarization coupling device 154 has a mirror 156, a polarizer 158 and a retardation plate in the form of a λ / 2 plate 160. The polarization coupling device 154 is designed as one, in particular a single, component.

[0183] The laser beams 34 are linearly polarized. The linear polarizations of the laser beams 34 are aligned parallel to one another before passing through the polarization coupling device 154. In other words, before passing through the polarization coupling device 154, the polarization of all laser beams 34 is aligned in the same direction.

[0184] The λ / 2 plate 160 is arranged such that the laser beams 34 of the first laser beam group 150 pass through the λ / 2 plate. The λ / 2 plate 160 is configured to rotate the polarization of the laser beams 34 of the first laser beam group 150 by 90°. As a result, the polarization of the laser beams 34 of the first laser beam group 150 is aligned orthogonally to the polarization of the second laser beam group 152.

[0185] After passing through the λ / 2 plate, the laser beams 34 of the first laser beam group 150 strike the polarizer 158. The polarizer 158 is configured to reflect or transmit the laser beams 34 depending on their polarization. In the illustrated embodiment of the Fig. 12, the polarizer 158 reflects the laser beams 34 of the first laser beam group 150 due to the orientation of their polarization.

[0186] The second laser beam group 152 strikes the mirror 156 as it passes through the polarization coupling device 154. The second laser beam group 152 is deflected by 90° by the mirror 156. By deflecting the second laser beam group 152 by means of the mirror 156, the second laser beam group 152 is directed onto the polarizer 158. In the illustrated initial example of the Fig. 12, the polarizer 158 transmitted the laser beams 34 of the second laser beam group 152 due to the orientation of their polarization.

[0187] The polarizer 158 spatially superimposes the laser beams 34 of the first laser beam group 150 with the laser beams 34 of the second laser beam group 152 to form the output laser beam 98. In other words, the output laser beam 98 is formed by means of the polarizer 158 by spatially superimposing the laser beams 34 of the first laser beam group 150 with the laser beams 34 of the second laser beam group 152.

[0188] Fig. Fig. 15 schematically shows a section of a cross-section of the output laser beam 98 in the output 12, wherein for reasons of clarity not all laser beams 34 of the laser emitter devices 14 are shown in Fig. 15. The laser beams 34 of the second laser beam group 152 are in Fig. 15 shown in dashed lines.

[0189] The output laser beam 98 is formed by polarization coupling by means of the polarization coupling device 154 such that a laser beam 34 of the second laser beam group 152 is arranged at the output between two adjacent laser beams 34 of the first laser beam group 150. The laser beams 34 of the first laser beam group 150 and the laser beams 34 of the second laser beam group 152 overlap in certain regions. However, an embodiment in which the laser beams 34 do not overlap is also conceivable.

[0190] In an alternative embodiment not shown, the output laser beam is formed by spatially superimposing the laser beams of the first laser beam group with the laser beams of the second laser beam group by wavelength coupling by means of a wavelength coupling device of the laser emitter arrangement.

[0191] In Fig. 16 to 21, a further embodiment of a laser emitter arrangement 10 is shown, wherein identical and functionally equivalent elements are given the same reference numerals and in this respect reference is made to the above explanations regarding the embodiments of the Fig. 1 to 15, so that essentially only the existing differences are discussed.

[0192] The optical device 100 is integrally connected to the polarizer 158 of the polarization coupling device 154 and the mirror 156 of the polarization coupling device 154, forming a coupling element 162 of the laser emitter arrangement 10. In other words, the coupling element 162 is embodied as a single component. The coupling element 162 is made of quartz glass.

[0193] The λ / 2 plate 160 of the polarization coupling device 154 is designed separately from the coupling element 162.

[0194] Fig.21 shows the coupling element 162 of the laser emitter arrangement 10 and the base plate 16.

[0195] The optical device 100 is formed by a flat entrance surface 164 of the coupling element 162. The flat entrance surface 164 is oriented obliquely to the flat surface section 26. Each laser beam 34 strikes the flat entrance surface 164 at an angle of incidence 106.

[0196] The flat entrance surface 164 forms a phase boundary for the laser beams 34. Each propagation direction 36 of the laser beams 34 is changed by refraction at the flat entrance surface 164 toward the flat surface section 26. As a result, the propagation directions 36 of the laser beams 34 are changed by the deflection angle 108.

[0197] After passing the flat entrance surface 164, the propagation directions 36 of the laser beams 34 are aligned parallel to the flat surface section 26.

[0198] A method according to the invention is designed to operate a previously described laser emitter arrangement.

Claims

[1] Laser emitter arrangement (10) for providing an output laser beam (98) at an output (12) of the laser emitter arrangement (10), comprising: - a base plate (16) with a flat surface section (26), and - a plurality of laser emitter devices (14) arranged on the flat surface portion (26) and fixed to the base plate (16), - wherein each laser emitter device (14) is arranged to generate a laser beam (34), - wherein the output laser beam (98) is formed from the laser beams (34) of the laser emitter devices (14). [2] Laser emitter arrangement (10) according to claim 1, - wherein each laser emitter device (14) has a laser emitter output (62) from which the laser beam (34) emerges, - wherein each laser emitter output (62) is spaced a distance from the planar surface portion (26), - wherein the distances of the laser emitter outputs (62) from the flat surface section (26) are of the same amount. [3] Laser emitter arrangement (10) according to one of the preceding claims, - wherein each laser emitter device (14) is adapted to emit the laser beam (34) in an emission direction (48), - wherein the radiation directions (48) are aligned parallel to each other. [4] Laser emitter arrangement (10) according to one of the preceding claims, - wherein each laser emitter device (14) has at least one emitter (28), - wherein each laser emitter device (14) is adapted to emit the laser beam (34) in an emission direction (48), - wherein each emission direction (48) has an oblique course with respect to the flat surface section (26) and / or with respect to a longitudinal axis (32) of the emitter (28). [5] Laser emitter arrangement (10) according to one of the preceding claims, - wherein the plurality of laser emitter devices (14) are arranged on the planar surface portion (26) to form at least one laser emitter row (66, 122, 124). [6] Laser emitter arrangement (10) according to one of the preceding claims, - wherein the laser emitter devices (14) are arranged on the flat surface section (26) to form a first laser emitter row (122) and a second laser emitter row (124). [7] Laser emitter arrangement (10) according to claim 6, - wherein the first laser emitter row (122) and the second laser emitter row (124) are aligned parallel to each other. [8] Laser emitter arrangement (10) according to claim 6 or 7, - wherein the first laser emitter row (122) and the second laser emitter row (124) are arranged offset from one another. [9] Laser emitter arrangement (10) according to one of claims 6 to 8, - wherein the output laser beam (98) is formed by polarization coupling and / or by wavelength coupling of the laser beams (34) of the laser emitter devices (14) of the first laser emitter row (122) with the laser beams (34) of the laser emitter devices (14) of the second laser emitter row (124). [10] Laser emitter arrangement (10) according to claim 9, - wherein the output laser beam (98) is formed such that a laser beam (34) of the second laser emitter row (124) is arranged at least between two adjacent laser beams (34) of the first laser emitter row (122). [11] Laser emitter arrangement (10) according to one of the preceding claims, - wherein each laser emitter device (14) has at least one emitter (28), - wherein a longitudinal axis (32) of the emitter (28) of each laser emitter device (14) runs parallel to the flat surface section (26). [12] Laser emitter arrangement (10) according to one of the preceding claims, - wherein the laser emitter arrangement (10) has a housing, - wherein the base plate (16) forms a wall section of the housing. [13] Laser emitter arrangement (10) according to one of the preceding claims, - wherein each laser beam (34) travels a propagation distance from the laser emitter device (14) generating the laser beam (34) to the output (12) of the laser emitter arrangement (10), - wherein the output laser beam (98) is formed from the laser beams (34) of the laser emitter devices (14) as a function of the propagation distances from the laser emitter devices (14) to the output (12). [14] A method for providing an output laser beam (98) at an output (12) of a laser emitter arrangement (10), the method comprising the steps of: - arranging a plurality of laser emitter devices (14) of the laser emitter arrangement (10) on a flat surface section (26) of a base plate (16) of the laser emitter arrangement (10), - Attaching the laser emitter devices (14) to the base plate (16), - generating laser beams (34) by means of a plurality of laser emitter devices (14), and - forming the output laser beam (98) from the laser beams (34) of the laser emitter devices (14).

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