1kW单模全光纤激光器实验研究

Experiment research of 1 kW single mode all fiber laser

研究了高功率下光纤激光器实现单模激光输出的模式控制方式,分析了输出功率1kW的连续全光纤激光器的实现方法。采用一级振荡、一级放大的主振荡功率放大方式,实现了工作波长1.08μm,最大输出功率1.05 kW的全光纤连续激光输出,光-光转换效率77%,光束质量Mx2=1.43、My2=1.42。分析了光束质量变差的原因,认为在高功率下光纤弯曲导致原先在纤芯中传输的激光部分被泄露到包层中,在包层中传输激光使光束质量变差。针对某些特殊用途,对中心波长的稳定度进行了研究,经测量发现随着输出功率的增大,中心波长无明显变化。

The method of controlling mode, by which single mode laser output was achieved under high power was studied, and the method to achieve all fiber laser with 1 kW continuous output was analyzed. The ways of master-oscillator power amplifier which included a laser oscillator stage and a booster amplifier stage were used. The continuous laser with wavelength of 1.08 μm and biggest output power of 1.05 kW was achieved respectively. The optical-optical conversion efficiency was 77%. The beam quality 2 2 was M^2_x =1.43 and M^2_y =1.42. The reason for deteriorative beam quality was analyzed. In high power, part of laser which was transmitted in the fiber core originally, was leaked to inner cladding by fiber bending. Then, the beam quality is worsened by laser which was transmitted in inner cladding. For some special use, the stabilization of central wavelength was studied. Through measurement, there is no obvious variation in central wavelength with the output power increase.