Abstract: Methods and systems for generating a laser beam with different beam profile characteristics are provided. In one aspect, a method includes coupling an input laser beam into one fiber end of a multi-clad fiber, in particular a double-clad fiber and emitting an output laser beam from the other fiber end of the multi-clad fiber. To generate different beam profile characteristics of the output laser beam, the input laser beam is electively coupled either at least into the inner fiber core of the multi-clad fiber or at least into at least one outer ring core of the multi-clad fiber, or a first sub-beam of the input laser beam is coupled into at least into the inner fiber core of the multi-clad fiber and a second, different sub-beam of the input laser beam is coupled at least into the at least one outer ring core of the multi-clad fiber.

Abstract: A processing optical unit for workpiece processing includes a birefringent polarizer configured to split at least one input laser beam into a pair of partial beams polarized perpendicularly to one another. The processing optical unit further includes a focusing optical unit arranged downstream of the birefringent polarizer in the beam path and configured to focus the pair of partial beams onto focus zones in a focal plane. The processing optical unit is configured to produce at least partly overlapping focus zones of the pair of partial beams.

Abstract: The disclosure provides methods for calibrating processing machines for the production of 3D components by irradiation of powder layers, wherein the processing machine includes a scanner device for positioning a laser beam in a processing field in which a height-adjustable construction platform for the application of the powder layers by sweeping at least two, e.g., three markings, e.g., in the form of spherical retroreflectors, which are applied on the construction platform and/or on a preform, by the laser beam, detecting laser radiation reflected back from the markings into the scanner device, determining actual positions of the markings, determining deviations of the actual positions of the markings from setpoint positions of the markings, and calibrating the processing machine by correcting the positioning of the laser beam and/or the position of the construction platform using the determined deviations. The disclosure also relates to associated processing machines.

Abstract: An optical arrangement converts a laser beam into a line-type beam having a line-type beam cross-section that extends along a line direction with a non-vanishing intensity. The arrangement has: reshaping optics having: an input aperture through which the laser beam is radiated in; and an elongate output aperture, the reshaping optics being configured such that the laser beam radiated in is converted into a beam packet with beam segments that emerge through the output aperture; homogenization optics, which contribute to the conversion of the beam packet into the line-type output beam, and by which different beam segments are mixed and superposed along the line direction; and redirection optics configured to redirect the laser beam such that an incidence position/direction of laser beam on the input aperture is changed in dependence on time.

Abstract: The present disclosure relates to methods and devices for monitoring a welding process for welding at least one glass workpiece to another workpiece, the workpieces being welded together in a process zone that is exposed to a processing beam, e.g., to a laser beam, such as an ultra-short-pulse laser beam, wherein radiation emitted by the process zone and originating from at least one of the workpieces is detected in a spatially resolved manner.

Abstract: The disclosure relates to methods and devices for producing three-dimensional components by selective solidification from build material applied in layered fashion by providing a building cylinder in which substrate plates are stacked one above the other, applying the build material to the uppermost substrate plate with an application device, generating at least one beam and directing the beam onto the applied layer of the build material, moving the application device along a working plane at least along the building cylinder and at least one collecting chamber for non-solidified build material, and moving the substrate plate out in relation to the building cylinder such that a bottom of the substrate plate lies in the working plane, wherein the substrate plate which has been moved out of the building cylinder is transferred by the application device from the building cylinder into the adjacent collecting chamber.

Abstract: The present disclosure relates to methods and systems for monitoring a welding process for welding at least one glass workpiece to another workpiece, e.g., also made of glass, wherein a weld seam is formed in the workpieces in a process zone that is exposed to a pulsed processing beam, e.g., to a pulsed laser beam, such as an ultra-short-pulse laser beam, wherein the radiation emitted by the process zone is detected in a time-resolved manner.

Abstract: A method for joining copper hairpins includes providing at least two ends to be joined to one another of the copper hairpins, and joining the copper hairpins. The copper hairpins are joined by laser beam welding with a machining beam having a wavelength of less than 1000 nm.

Abstract: A hairpin welding method welds wire ends of at least two copper wires, arranged flush next to one another, to one another by a laser beam. The laser beam is generated with a beam cross section that impinges on the wire ends at an end side and has a round core region and a ring region surrounding the round core region. A ratio of an external diameter of the ring region to a diameter of the core region is between 7:1 and 2:1. A ratio of a laser power in the core region to a laser power in the ring region is between 10:90 and 70:30.

Abstract: A method for laser welding a multiplicity of foils onto a carrier includes arranging the foils one on top of the other to provide a foil stack, folding the foil stack to provide a folded region of the foil stack that protrudes up from two side regions of the foil stack, pressing the side regions against the carrier, and pressing together the side regions toward the folded region. The method further includes welding the foils to one another and to the carrier by directing a laser beam onto the folded region and moving the laser beam along the folded region.

Abstract: An apparatus for laser machining a workpiece includes a beam shaping device for forming a focal zone from an input laser beam incident on the beam shaping device, and a telescope device for imaging the focal zone into a material of the workpiece. The beam shaping device is configured to impose a phase on a beam cross section of the input laser beam in such a way that the focal zone extends along a longitudinal centre axis which is curved at least in certain portions. The telescope device is assigned a beam splitting device for splitting an output laser beam output coupled from the beam shaping device into a plurality of polarized partial beams, each of which has one of at least two different polarization states. The focal zone has an asymmetrical cross section in a plane oriented perpendicular to the longitudinal centre axis.

Abstract: An apparatus for laser machining a workpiece in a machining plane includes a first laser machining unit for forming a first focal zone which extends in a first main direction of extent, and at least one further laser machining unit for forming at least one further focal zone which extends in a further main direction of extent oriented transversely to the first main direction of extent. The first focal zone and the at least one further focal zone are spaced apart from one another parallel to the machining plane at a work distance. The first laser machining unit and the at least one further laser machining unit are movable in an advancement direction that is oriented parallel to the machining plane. The workpiece comprises a material that is transparent to a laser beam which respectively forms the first focal zone and the at least one further focal zone.

Abstract: The disclosure provides methods of additive manufacture of components in layers in a powder bed by at least two laser beams that can be deflected two-dimensionally over the same powder bed region. Each laser focal spot is projected onto the power bed and is or is set to a diameter of less than or equal to 300 ?m. Components to be produced in the powder bed region are manufactured by each of the laser beams, and each individual surface contour of the component is manufactured solely by one of the laser beams.

Abstract: A workpiece processing machine that includes: a beam emission head for providing a beam for processing the workpiece, an optical interferometer for splitting, redirecting, and detecting the beam, an adjustment element for changing a second portion of a power of the beam redirected from a retroreflector to a detector, and a control unit for actuating the adjustment element to control a ratio between a first power portion of the beam redirected from the workpiece to the detector and the second power portion of the beam redirected from the retroreflector to the detector to a target ratio.

Abstract: The present disclosure relates to calibrating scanner devices for positioning laser beams in a processing field, and includes, e.g.: arranging a retroreflector in the processing field of the scanner device, the processing field being formed in a processing chamber for irradiating powder layers; detecting laser radiation reflected back into the scanner device when the laser beam passes over the retroreflector; determining an actual position of the laser beam in the processing field using the detected laser radiation; and calibrating the scanner device by correcting a laser beam target position specified for the scanner device in the processing field using the determined actual position of the laser beam in the processing field.

Abstract: The invention relates to a method for dividing a transparent workpiece (1) by means of pulsed laser radiation (2) by way of creating a beam convergence zone (3) in the volume of the workpiece, in which the intensity of the laser radiation (2) exceeds a threshold value for non-linear absorption, wherein the beam convergence zone (3) and the workpiece (1) are moved relative to each other, thereby creating a two-dimensional weakening in the workpiece (1) extending along a predetermined separating line (4), and wherein the workpiece (1) is subsequently divided along the separating line (4). The invention proposes that by selecting the duration of the energy input generated by the non-linear absorption of the pulsed laser radiation and by spatial beam shaping, non-linear propagation of the laser radiation (2) in the volume (1) of the workpiece outside the beam convergence zone (3) is suppressed.

Abstract: Methods and systems for generating a laser beam with different beam profile characteristics are provided. In one aspect, a method includes coupling an input laser beam into one fiber end of a multi-clad fiber, in particular a double-clad fiber and emitting an output laser beam from the other fiber end of the multi-clad fiber. To generate different beam profile characteristics of the output laser beam, the input laser beam is electively coupled either at least into the inner fiber core of the multi-clad fiber or at least into at least one outer ring core of the multi-clad fiber, or a first sub-beam of the input laser beam is coupled into at least into the inner fiber core of the multi-clad fiber and a second, different sub-beam of the input laser beam is coupled at least into the at least one outer ring core of the multi-clad fiber.

Abstract: Laser beam welding a workpiece includes: generating first and second beam areas on the workpiece by first and second laser beams, respectively. The beam areas are guided in a feed direction relative to the workpiece. Centroids of the beam areas are not coinciding. The first beam area runs ahead of the second beam area. A length of the first beam area, measured transversely to the feed direction, is greater than or equal to that of the second. A surface area of the first beam area is greater than that of the second. A width of the first beam area, measured in the feed direction, is greater than or equal to that of the second. A laser power of the first laser beam is greater than that of the second. The second laser beam is irradiated into a weld pool generated by the first laser beam.

Abstract: For material processing of a material, which is in particular for a laser beam to a large extent transparent, asymmetric shaped modifications are created transverse to the propagation direction of the laser beam. Thereby, the laser beam is shaped for forming an elongated focus zone in the material, wherein the focus zone is such that it includes at least one intensity maximum, which is transverse flattened in a flattening direction, or a transverse and/or axial sequence of asymmetric intensity maxima, which are flattened in a sequence direction. After positioning the focus zone in the material, a modification is created and the material and the focus zone are moved relative to each other in the or across to the flattening direction or in the or across to the sequence direction for forming a crack along an induced preferred direction.

Abstract: The disclosure relates to processing machines and methods for producing three-dimensional components by irradiating powder with a processing beam, the machines including a container with a moveable support for the powder, as well as an irradiating device with a scanner device for aligning the processing beam on a processing field at an opening of the container. The irradiating device includes a heating device that includes a heating radiation source for generating a heating beam for heating the powder from above and including a beam shaping optical unit configured to convert a first beam profile of the heating beam into a second beam profile, e.g., a ring-shaped beam profile, of the heating beam.