激光热效应对光束控制系统发射光束质量的影响  

Laser Thermal Effects in Beam Control System on the Emitted Laser Quality

作　　者：金钢[1] 刘顺发[1] 李树民[2] 陈洪斌[1] 马佳光[1] 

机构地区：[1]中国科学院光电技术研究所国家863计划光束控制重点实验室,四川成都6102092 [2]中国空气动力研究与发展中心计算空气动力学研究所,四川绵阳621000

出　　处：《中国激光》2002年第10期895-899,共5页Chinese Journal of Lasers

摘　　要：采用数值计算方法分析了较高能量密度激光在光束控制系统内所产生的热效应对远场光斑质量和能量分布的影响。激光传输由近轴波方程描述 ,采用像屏法和快速傅里叶变换技术求解。激光加热引起的气流扰动及气体介质密度变化采用完全的Navier Stokes方程描述 ,以便考虑各种不同因素的影响。Navier Stokes方程求解采用LU SGS分解技术。数值计算结果表明 ,在典型情况下 ,热晕引起的附加热相位会明显增大发射激光的发散 ,降低目标处激光能量集中度和远场光斑质量。The thermal effects, produced by the high energy laser in a beam control system, are numerically analyzed in this paper. The effects on the laser density and beam facula quality at far field are studied in particular. The propagation of laser is described by the paraxial wave equations, solved by the phase screen technique and the FFT method. The thermal turbulence motion and the air density variation are governed by the complete Navier Stokes equations, so that the variety factors could be in consideration. The Navier Stokes equations are solved by using the LU SGS factorization technique. The numerical results show that, with the additional initial thermal phase at the emitter exit, the energy density and the quality of the laser beam at far field would be prominently degraded for the typical situations.

关 键 词：热效应 光束控制系统 光束质量 激光传输 相屏法 热晕 快速傅里叶变换 NAVIER-STOKES方程 气动光学 

分 类 号：TN012[电子电信—物理电子学]