A device is disclosed for combining optical radiation by utilizing the polarization properties of light and which includes a plane-parallel optically transparent plate with a refraction index n which has an optically active first surface on which a first optical beam (active beam) impinges, and a second optically active surface parallel to the first one on which a second optical beam (targeting beam) impinges at the exit location of the first beam from this second surface. The plane-parallel plate is arranged relative to the beams or the beam paths to be coupled in such a manner that the first beam impinges on the first surface of the plate and the second beam impinges on the second surface of the plate and that both do this at an angle &agr; which is equal to or approximately equal to the Brewster angle corresponding to the refractive index n of the plate. The first and the second beam are linearly polarized, the plane of polarization of the first beam being parallel to the plane of incidence of the device and the plane of polarization of the second beam being vertical to the plane of incidence of the device.