基于反射体布拉格光栅谱组束的设计

Design of spectral beam combining based on reflecting volume Bragg grating

针对反射体布拉格光栅谱组束中缺乏精密控制仪器的实验条件,采用透镜作为光束入射角和准直控制器件,设计了一种结构简单的谱组束系统。基于衍射效率方程,得到了光栅最佳设计参数;基于像差理论,得到了透镜最佳设计参数。针对该设计系统,对影响组束效果的因素进行了分析,并对组束效果进行了预测。结果表明:当激光束的谱宽小于1.5 nm时,设计系统的组束效率能超过90%;而当光束的谱宽达到2.1nm时,设计系统也能获得超过88.7%的组束效率。

For the lack of precise control tools in spectral beam combining using reflecting volume Bragg grating,a simple experimental setup was designed using lenses as control elements of beam incident angle and collimation.The optimal grating parameters were derived based on the formula of diffraction efficiency,and the optimal lens parameters were derived based on the formula of aberrations.For the designed combining system,the influencing factors of combining results were analyzed,and the combining results for two laser beams with wavelengths of 1 553 nm and 1 559 nm were calculated.The results show that the combining efficiency of more than 90% can be achieved when the spectral widths of the two beams are less than 1.5 nm,and the combining efficiency of more than 88.7% can also be reached when the spectral widths of the two beams are equal to 2.1 nm.