高功率非相干光纤激光组束方法研究

The research on the method of high power incoherent fiber laser beam combination

提高非相干光纤激光组束功率需要较高的光栅衍射效率,通过理论分析和数值仿真,结果表明光栅衍射效率对组束中心波长不敏感,而随着组束波长带宽的增大而急剧减小。为了增加可参与组束的光纤激光器数目,同时确保较高的光栅衍射效率,应将光栅频率f控制在200-400mm^-1,光栅厚度t在1-2mm,理论上可以获得10kW量级的组束激光。

To increase the output power ot incoherent fiber laser beam combination needs high grating diffraction efficiency. Through theoretic analysis and numerical simulations, it has been proved that the diffraction efficiency is not sensitive to central wavelength in combination, but decreases rapidly with the increase of wavelength bandwidth. In order to increase the number of available fiber lasers, meanwhile guarantee the diffraction efficiency to be at some high levd, the grating frequency f should be chc, sen between 200 and 400mm^-1, the grating thickness t should be chosen between 1 and 2mm. Theoretically the combined output power at 10 kilowatt could be reached.