Device for wavelength combining of laser beams

A device for wavelength coupling of laser beams (2a, . . . 2n) with different wavelengths (λ1, . . . λn), comprising: at least one laser source for generating a plurality of laser beams (2a, . . . , 2n), and an overlapping device for spatial overlapping of the plurality of laser beams (2a, . . . , 2n) for forming an overlapped laser beam with a plurality of wavelengths (λ1 . . . λn). The device has a feedback device arranged between the laser source and the overlapping device for feeding a radiation proportion of the laser beams (2a, . . . , 2n) to be overlapped back to the laser source, the feedback device comprising a partially reflecting angle-dispersive optical element, in particular a partially reflecting diffraction grating. The overlapping device may, for example, be configured as a transmitting or reflecting diffraction grating whose optical properties are adapted to the optical properties of the partially reflecting diffraction grating to overlap the laser beams (2a, . . . , 2n) in an essentially dispersion-free manner.