Irradiation system for an additive manufacturing device

An irradiation system for a device for laser-based additive manufacturing, the system comprising:

• a first beam source configured to output a first laser beam, and a second beam source configured to output a second laser beam, wherein the second laser beam has a beam quality higher than a beam quality of the first laser beam;
• a common scanner optics arranged to focus the first laser beam and the second laser beam within a manufacturing space of the device;
• and
• a beam guiding system comprising a first beam path along which the first laser beam is guided from the first beam source to the scanner optics during operation of the system, and a second beam path along which the second laser beam is guided from the second beam source to the scanner optics during operation of the system, wherein the beam guiding system further comprises a beam combiner arranged to superimpose the first beam path and the second beam path, wherein
• the beam guiding system further comprising a transport fiber having a central area for guiding a beam having a high beam quality, and a cladding area surrounding the central area, for guiding a beam having a low beam quality, wherein the first laser beam is couplable into the central area of the transport fiber and the second laser beam is couplable into the cladding area surrounding the central area such that, when the laser light exits the transport fiber, a beam portion originating from the first laser beam has a beam quality lower than that of a beam portion originating from the second laser beam, and/or
• wherein the beam guiding system further comprises a fiber bundle structure, including at least one fiber core for guiding a beam having a high beam quality, and additional fiber cores for guiding a beam having a low beam quality, wherein the first laser beam is couplable into the at least one fiber core, and the second laser beam is couplable into the additional fiber cores by the beam combiner such that, when the laser light exits the transport fiber, a beam portion originating from the first laser beam has a beam quality lower than that of a beam portion originating from the second laser beam.

A method for setting a spatially adapted irradiation for additive manufacturing of a workpiece in a laser-based additive manufacturing device comprising a scanner optics and a powder bed, the method comprising:

• providing a first laser beam and a second laser beam, wherein the second laser beam has a beam quality higher than a beam quality of the first laser beam;
• adjusting energy inputs of the first laser beam and the second laser beam in a superimposed beam path in the scanner optics;
• and
• scanning the first laser beam and the second laser beam over the powder bed by alternatingly or simultaneously irradiating the powder bed with the first laser beam and the second laser beam,
• wherein the laser-based additive manufacturing device further comprises an irradiation system including a diode pump laser, a laser resonator and a scanner optics, and wherein
• providing the second laser beam comprises pumping the laser resonator with a pump laser beam of the diode pump laser, and
• adjusting the energy inputs of the first laser beam and the second laser beam comprises coupling out a portion of the pump laser beam before entry into the laser resonator and/or alternatingly or simultaneously coupling the first laser beam and the second laser beam into the superimposed beam path of the scanner optics.

A method for setting a spatially adapted irradiation for additive manufacturing of a workpiece in a laser-based additive manufacturing device with a scanner optics and a powder bed, the method comprising:

• providing a first laser beam and a second laser beam, wherein the second laser beam has a beam quality higher than a beam quality of the first laser beam;
• adjusting energy inputs of the first laser beam and the second laser beam in a superimposed beam path in the scanner optics;
• and
• scanning the first laser beam and the second laser beam over the powder bed by alternating or simultaneously irradiating the powder bed with the first laser beam and the second laser beam,
• wherein providing the first laser beam and the second laser beam comprises coupling the first laser beam and the second laser beam into a transport fiber, wherein the second laser beam is coupled into a central area of the transport fiber, and a portion of a pump laser beam is coupled into a cladding area of the transport fiber such that, when light is emitted from the transport fiber, a beam portion originating from the second laser beam has a beam quality higher than a beam quality of a beam portion originating from the first laser beam .