AN EFFICIENT METHOD FOR ENHANCING THE FILLING FACTOR OF THE APERTURE FOR COHERENT-BEAMING-COMBINING (CBC) USING THIN-FILM COATED GLASS

摘要

Aperture technology, which influences the combining efficiency, is the key factor for Coherent-Beam-Combining (CBC). By using beam combiner with high performances, coherent combining of fiber lasers can provide the chance to increase the output intensity more efficiently. This presents a method to manufacture the beam combiner for CBC by using a thin-film coated glass plate. This method can increase the effective filling factor of aperture, and therefore eliminate far-field side-lobes by enlarging the number of sub-apertures and decreasing the distance between the sub-apertures for an output aperture with a constant size. The fabrication of this thin-film coated glass costs less and the coated glass has better stability than other beam combiners. In order to earn high efficiency for CBC, we also exploit physical and geometrical optics to build the model. Theoretically, this method can raise the coherent combining efficiency almost to 100%. Additionally, based on this method, a new conception of Multiple-beam Interference of Multi-beams is offered.