中国激光, 2007, 34 (5): 628, 网络出版: 2007-05-23
高功率横流CO2激光器的锥面反射镜谐振腔
90° Conical Reflector Resonator for High Power Transverse Flow CO2Laser
激光器 气体激光器 横流CO2激光器 直角锥面反射镜 平-锥谐振腔 衍射积分方程 lasers gas laser transverse flow CO2 laser 90° conical reflector plane-cone resonator diffraction integrals equation
摘要
根据针-板放电5 kW横流CO2激光器的结构特点,设计并实验研究了直角锥面镜作为全反射镜的谐振腔。在菲涅耳-基尔霍夫理论的基础上,引入柯林斯公式并考虑增益影响,推导了锥面谐振腔的衍射积分方程,并进行了相应的模拟计算。研究结果表明,在高功率横流CO2激光器中锥面反射镜与平面输出镜相配合使用组成稳定腔,获得了TEM30的低阶模输出; 由于锥面反射镜受加工精度的影响中心残留有加工盲孔,导致TEMmn(m=0,n≠0)的模损耗较大不易耦合输出; 而镜面中心场分布很弱的其他低阶模因损耗小,则会优先输出。
Abstract
Considering the structural characteristics of 5 kW transverse flow continuous wave CO2 laser electrically excited with pin-to-flat discharge, the 90° conical reflector designed as the resonator cavity of totally reflective mirror is investigated. Based on the Fresnel-Kirchhoff theory, the diffraction integrals equation of conical resonator is deduced by using Collins formula and taking gain influence into account. The results indicate that the resonator composed of conical reflector and plane output mirror is stable and low-step output modes are acquired for high power transverse flow CO2 laser. Limited by the processing accuracy, there is a processing residual blind-hole in the center, which brings considerable loss for TEMmn (m=0, n≠0) modes, so its output is difficult. However, the low-order modes of weak center field distribution for less loss have prior output.
武建强, 唐霞辉, 秦应雄, 程祖海, 李宏棋, 钟如涛. 高功率横流CO2激光器的锥面反射镜谐振腔[J]. 中国激光, 2007, 34(5): 628. 武建强, 唐霞辉, 秦应雄, 程祖海, 李宏棋, 钟如涛. 90° Conical Reflector Resonator for High Power Transverse Flow CO2Laser[J]. Chinese Journal of Lasers, 2007, 34(5): 628.