Generating multiple laser pulses by superimposing laser radiation

Method for generating a repetition of laser pulses consisting of pulse bursts, comprising the following method steps:

• generating pulsed laser radiation in the form of a sequence of temporally equidistant individual pulses;
• splitting the laser radiation into at least two spatially separate input beam paths of different length;
• superimposing the laser radiation propagating along the at least two input beam paths into pulse bursts in an output beam path;
• coupling the superimposed laser radiation propagating along the output beam path into an optical waveguide, coupling the superimposed laser radiation propagating along the output beam path into an optical waveguide, which is a hollow core fiber, a Kagome fiber, or a large-mode- area fiber, wherein higher modes are excited in the optical waveguide due to deviations of the superimposed laser radiation with respect to the beam position or direction, and wherein the optical waveguide guides the laser radiation primarily in a fundamental mode, so that the laser radiation propagating in the optical waveguide experiences a higher loss in higher modes than in the fundamental mode;
• and
• coupling out the laser radiation from the optical waveguide such that the laser radiation is available for material processing at an output side of a decoupling optical element.

A device comprising:

• a laser to generate pulsed laser radiation formed as a sequence of temporally equidistant individual pulses;
• a combination element coupled to the laser by an input path, wherein the laser radiation propagates from the laser to the combination element via the input path, the combination element superimposes first and second portions of the laser radiation into pulse bursts in an output beam path, the first portion of the laser radiation propagating along a first input beam path prior to being superimposed, the second portion of the laser radiation propagating along a second input beam path prior to being superimposed, the first and second input beam paths having different lengths;
• coupling optics arranged in the output beam path;
• an optical waveguide with an input side coupled to the coupling optics, the coupling optics to couple the laser radiation superimposed in the output beam path into the input side of the optical waveguide such that higher modes are excited in the optical waveguide due to a configuration of the device with deviations of the superimposed laser radiation with respect to beam position or direction, the optical waveguide to guide the laser radiation primarily in a fundamental mode such that laser radiation propagating in the optical waveguide experiences a higher loss in the higher modes than in the fundamental mode;
• and
• decoupling optics to couple out the laser radiation from the optical waveguide such that the laser radiation is available for material processing at an output side of the decoupling optics.