Spatially splitting or combining radiation beams

Abstract

A method of spatially splitting a primary radiation beam () with a first radiation component () including an optical wavelength and a second radiation component () having a wavelength shorter than the first radiation component wavelength, said second radiation component () having a second or higher harmonic wavelength relative to the optical wavelength, comprises directing the primary radiation beam () onto a deflection mirror () having a reflective mirror surface () and carrying a refractive plate element (), reflecting the first radiation component () at the reflective mirror surface () and reflecting the second radiation component () at an exposed plate surface () of the refractive plate element (), wherein the reflected radiation components () travel along different beam paths. Furthermore, a method of spatially combining a first beam path of a first radiation component () and a second beam path of a second radiation component () is described, wherein the beam splitting method is reversed. Further more, an optical device for implementing the above methods and applications of the methods are described.