Abstract: A laser machining head for material processing with a laser includes: a focusing optics for focusing the laser beam; an exit opening for the laser beam; an optical sensor arrangement; a coupling optics for coupling light entering through the exit opening out of the beam path of the laser beam to the sensor arrangement; an optics for adjusting a focal position of the laser beam, which has at least one adjustable optical element for adjusting the focal position of the laser beam; and a compensating optics for correcting a chromatic aberration, caused by the focusing optics, of the light coupled out to the sensor arrangement. The compensating optics are arranged between the coupling optics and the sensor arrangement and are arranged for adjusting a focal position of the light coupled out to the sensor arrangement.

Abstract: A device for determining a focus position of a laser beam in a laser machining system has a first optical element which is designed to reflect a portion of the laser beam in order to uncouple a first sub-beam of the laser beam, a second optical element which is designed to reflect another portion of the laser beam in order to uncouple a second sub-beam of the laser beam substantially coaxially to the first sub-beam, a spatially-resolving sensor to which the first sub-beam and the second sub-beam can be directed, and an evaluation unit which is designed to determine a focus position of the laser beam on the basis of the first and second sub-beams hitting the spatially-resolving sensor.

Abstract: A device for determining a focus position of a laser beam in a laser machining system includes an optical element configured to reflect a portion of the laser beam for coupling out a first sub-beam of the laser beam, a spatially resolving sensor to which the first sub-beam can be directed, and an evaluation unit configured to determine a focus position of the laser beam based on an actual diameter of the first sub-beam incident on the spatially resolving sensor, a laser beam power, and calibration data.

Abstract: A deflection device for a laser machining head for deflecting a machining laser beam for machining a workpiece includes at least one mirror element which is deformable and/or is movably arranged in order to direct the machining laser beam to different positions on the workpiece. The mirror element includes at least one substrate and at least one reflective multilayer structure which is arranged on the substrate and in which a plurality of crystalline first layers having first refractive indices in a first range of values and a plurality of crystalline second layers having second refractive indices in a second range of values are arranged alternately one above the other. The first refractive indices of the crystalline first layers and the second refractive indices of the crystalline second layers are different from each other.

Abstract: A device for a laser machining system includes a laser beam optics for a machining laser beam with an arrangement of optical elements arranged one after the other in a beam path of the machining laser beam. With respect to a direction of propagation of the machining laser beam, a first outermost optical element of the arrangement of optical elements consists of a material with a thermal conductivity coefficient kT of 2 W/(m·K) or more.

Abstract: A method for identifying joining positions of workpieces includes capturing images of a joint by a camera, determining measurement data for the joining positions associated with a course of the joint from the images of the joint, determining a mathematical model of the joint course from a part of the measurement data, providing a curve based on the mathematical model for positioning a welding laser during a laser welding process along the curve.

Abstract: A method and a device for detecting a focal position of a laser beam, particularly a machining laser beam in a laser machining head, includes an optical element which is arranged in the laser beam converging toward the focal point and which is designed to outcouple a reflection from the laser beam path, and a sensor arrangement which is designed to detect beam characteristics of said laser beam in the region of the focal point in the laser extension direction, and which measures the outcoupled reflection of the laser beam at at least two locations that are offset to one another in the extension direction, in order to determine the current focal position.

Abstract: A device for determining a focal position of a laser beam, in particular a processing laser beam in a laser processing head, has an optical decoupling element for decoupling a partial beam from a beam path of the laser beam, a detector for detecting at least one beam parameter of the partial beam, and at least one optical element with an adjustable focal length, which is arranged in a region of the beam path of the partial beam between the optical decoupling element and the detector. Also disclosed is a laser processing head which includes a device of this type, as well as a method for determining a focal position of a laser beam.

Abstract: A device for a laser machining system includes a laser beam optics for a machining laser beam with an arrangement of optical elements arranged one after the other in a beam path of the machining laser beam. With respect to a direction of propagation of the machining laser beam, a first outermost optical element of the arrangement of optical elements consists of a material with a thermal conductivity coefficient kT of 2 W/(m·K) or more.

Abstract: A device is provided for setting a focus position (z) of a laser beam in a laser machining system. The device comprises a computing unit configured to calculate a time-dependent value zt of the focus position (z), wherein the computing unit calculates the time-dependent value zt of the focus position (z) based on a first parameter and a second parameter, wherein the first parameter indicates a magnitude A of a laser-power dependent focus shift per power unit and the second parameter indicates a time constant ? of a change in focus position due to a thermal lens by a factor of 1/e, and a control unit configured to use a mechanism for setting the focus position (z) to set the focus position (z) of the laser beam based on the time-dependent value zt of the focus position (z).

Abstract: The invention pertains to imaging optics (20) for material machining by means of laser irradiation, with said focusing optics comprising collimator optics (21) for collimating the divergent working laser beam (121) and focusing optics (22) for focusing the working laser beam (12) on a workpiece (14) to be machined, wherein the collimating optics (21) comprise a first lens or lens group (211) with positive focal length for focusing a working laser beam source (18) in a virtual intermediate focal point and a second movable lens or lens group (212) with negative focal length for focusing the virtual intermediate focal point to infinity. The invention furthermore proposes a laser machining head (1) with a housing (10), through which a working laser beam (12) can be guided. The inventive imaging optics (20) serve for generating a working focal point (15).

Abstract: A method and a device for detecting a focal position of a laser beam, particularly a machining laser beam in a laser machining head, includes an optical element which is arranged in the laser beam converging toward the focal point and which is designed to outcouple a reflection from the laser beam path, and a sensor arrangement which is designed to detect beam characteristics of said laser beam in the region of the focal point in the laser extension direction, and which measures the outcoupled reflection of the laser beam at at least two locations that are offset to one another in the extension direction, in order to determine the current focal position.

Abstract: A device for determining a focus position of a laser beam in a laser machining system has a first optical element which is designed to reflect a portion of the laser beam in order to uncouple a first sub-beam of the laser beam, a second optical element which is designed to reflect another portion of the laser beam in order to uncouple a second sub-beam of the laser beam substantially coaxially to the first sub-beam, a spatially-resolving sensor to which the first sub-beam and the second sub-beam can be directed, and an evaluation unit which is designed to determine a focus position of the laser beam on the basis of the first and second sub-beams hitting the spatially-resolving sensor.

Abstract: A device for determining a focus position of a laser beam in a laser machining system includes an optical element configured to reflect a portion of the laser beam for coupling out a first sub-beam of the laser beam, a spatially resolving sensor to which the first sub-beam can be directed, and an evaluation unit configured to determine a focus position of the laser beam based on an actual diameter of the first sub-beam incident on the spatially resolving sensor, a laser beam power, and calibration data.

Abstract: A method and a device for monitoring a beam guiding optics in a laser machining head during laser material machining, wherein a physical parameter of at least one optical element of the beam guiding optics is measured during the laser material machining. The parameter correlates with the degree of soiling of the at least one optical element. The current focal position is detected for focal position control by a spatially resolving sensor measuring the beam diameter in the region of the focus, and an evaluation circuit determines the current focal position from the output signal of the spatially resolving sensor and outputs an actuating signal for an actuator.

Abstract: A method is provided for identifying joining positions of workpieces. A laser machining head includes a housing through which a work laser beam path is guided. A device for carrying out the method for identifying joining positions of workpieces includes: a camera for capturing images of a joint of workpieces, the viewing beam path of which is coupled coaxially into the work laser beam path; and an illumination device, the illumination beam path of which is coupled coaxially into the viewing beam path and into the work laser beam path. In the method, images of a joint are captured by a camera, and from the images of the joint measurement data for the joining positions is determined. The measurement data is associated with the course of the joint. A model of the course of the joint is determined from a part of the measurement data, the model providing a measurement curve which is output for controlling a joining process and/or for determining additional quality characteristics.

Abstract: The invention pertains to imaging optics (20) for material machining by means of laser irradiation, with said focusing optics comprising collimator optics (21) for collimating the divergent working laser beam (121) and focusing optics (22) for focusing the working laser beam (12) on a workpiece (14) to be machined, wherein the collimating optics (21) comprise a first lens or lens group (211) with positive focal length for focusing a working laser beam source (18) in a virtual intermediate focal point and a second movable lens or lens group (212) with negative focal length for focusing the virtual intermediate focal point to infinity. The invention furthermore proposes a laser machining head (1) with a housing (10), through which a working laser beam (12) can be guided. The inventive imaging optics (20) serve for generating a working focal point (15).