高功率固体激光器锥形空间滤波孔应用

Application of cone pinhole in high energy solid-state laser system

锥形空间滤波孔是一种应用于高功率固体激光装置空间滤波的新型结构滤波小孔,其内部光滑的锥形结构可以有效滤除光束中的高频成分且避免等离子堵孔现象的发生。根据神光-Ⅲ主机装置结构特点,设计并加工了适用于主机装置的锥形空间滤波小孔,并开展了应用实验研究。通过与传统的平面结构滤波小孔对比可以看出,锥形小孔有效地避免了等离子体度堵孔现象,在与光束波前补偿技术配合使用条件下,保证光束顺利过孔,并成功实现了基频光7988J的满能量输出。

The cone pinhole that is a new structure pinhole is used for spatial filtering in high solid-state laser system. Its smooth inner surface will reflect the unwanted light to prevent plasma closure that easily happens in high energy running. The comparison between the cone pinhole and the washer pinhole shows that the cone one performs better under high energy running. The cone pinhole can avoid the plasma closure effect more efficiently. Combined with the adaptive optical technology, it ensures that the beam path is unobstructed. The use of seven-order cone pinholes in spatial filters makes the high energy output more stable, and the output energy reaches 7988 J, which means the single beam power density reaches 6.2 J/cm2. The method for desig- ning the cone pinhole is also presented.