Study on beam coherent combination technology with high power fiber lasers

光纤激光器由于其结构紧凑，使用轻便灵活，转换效率高，光束质量好，输出功率高等许多优点，在很多领域，如工业加工、通讯、医疗、科学研究和军事等具有广泛应用。随着应用领域的扩展，不但需要高功率而且还需要高质量的激光束。最近，单根光纤激光器输出功率不断提高，己经达到万瓦量级。但是Dawson等人的研究分析认为，按照目前的材料和条件，对于宽带光纤激光器，输出衍射极限激光的功率上限为36.6kW，对于窄带宽光纤激光器，输出上限则是} 8.6kW。近年来，国内外开展了各种组束技术的研究，其中的两种技术:光谱组束和相干组束技术，不仅能获得高功率激光输出时，还能不降低或提高光束质量。本文中，对高功率光纤激光器相干组束技术进行了详细的理论和实验研究。High-average-power lasers with difft-action-limited beam quality are desired by many applications such as cutting, welding and drilling. Cladding-pumped rare-earth.-doped fiber lasers offer an.excellent combination af compactness, high efficiency, and very good beam quality Large ouput power is possible because of the excellent therial dissipation properties of fibers to 10000W of output power in continuous-wave (CW)mode0has been demonstrated in a single trar Verse mode However; it's very.hard to scale the output power with a single-aperture Iaser'system Dawson et al. made a study on the output power of fiber lasers, which showed the maximum output power of fiber aasers, which showed the maximum output power of fiber lasers with the diffraction limit of 36.6kW for wide bandwidth and 1.86kW for narrow bandwidth, respectively: Other scaling approaches should be taken to closer consideration.:ln recent years, the technologies of beam cambinafion is the hot research topic, the spectral beam combination (SBC) and coherent beam combination (CBC) can not only offer the. high output power, but also retain or improve the beam quality. In this paper, the coherent beam combination with high-power fiber lasers is investigated theoretically and experimentally