Xu Jiao, Chen Junming, Chen Peng, Wang Yonglu, Zhang Yibin, Kong Fanyu, Jin Yunxia, Shao Jianda
Opt Express. 2018 Aug 20;26(17):21675-21684. doi: 10.1364/OE.26.021675.
Spectral beam combination is a promising method for high-radiance lasers with a good beam quality. With the increase of the combination power, the temperature of the multilayer dielectric grating (MDG) unavoidably increases, leading to surface heat distortion of the MDG. In this study, the temperature field equation of the MDG is derived, and the key factors influencing the MDG temperature are investigated. Furthermore, experiments are performed to confirm the calculation results. The results reveal that the increase of the thickness of the substrate can improve the power tolerance of the MDG but delays the stable output of beam laser; use of a substrate material with a large thermal conductivity can greatly reduce the temperature of the MDG.
光谱光束合成是一种用于获得高光束质量高辐射激光的很有前景的方法。随着合成功率的增加，多层介质光栅（MDG）的温度不可避免地升高，导致MDG的表面热畸变。在本研究中，推导了MDG的温度场方程，并研究了影响MDG温度的关键因素。此外，还进行了实验以验证计算结果。结果表明，增加衬底厚度可以提高MDG的功率容限，但会延迟激光束的稳定输出；使用具有大导热率的衬底材料可以大大降低MDG的温度。
