摘要
针对惯性约束聚变激光等离子体诊断系统的特殊需求．提出采用对数型轴锥镜来实现长焦深功能，并采用超高斯边缘匀滑、中心切趾及选择合适的器件参数等方法优化了长焦深器件的性能。模拟实验证明，为了得到满足要求的长焦深、小焦斑、小旁瓣和均匀的轴上及横向光场分布的聚焦光束，对数型轴锥镜的焦深应为3～5mm；元件中心须采用切趾，而且切趾半径应为15～60mm；元件边缘宜采用5阶超高斯匀滑。设计出焦深长达3mm、轴上光强均匀、旁瓣峰值小于中心强度的2％且横向光斑较均匀的长焦深器件，可以满足激光等离子体诊断的要求，并用菲涅耳衍射积分对该元件光场的模拟实验验证了该方法的可行性。
For the laser plasma diagnostic system in the inertial confinement fusion（ICF） drivers, the logarithmic axicon was adopted and improved by fifth-order super-Guassian edge smoothing, centre apodization and choosing suitable device parameters. The simulation experiments indicated that, to obtain a long-focal depth, small focused spot, small side lobe and homogeneous intensity focused beams in the on-axis and transverse directions, the focal depth of the logarithmic axicon should be 345 mm, the apodization radius should be 15460 mm, and the edge super-Guassian smoothing order should be 5. The long focal depth device whose focal depth was more than 3 mm, axial intensity distribution was uniform and the maximal relative intensity of the side lobe was less than 2% of the center intensity was designed, which could properly meet the diagnostic requirements of the laser plasma, and the Fresnel diffraction integral simulation experiments verified the feasibility of this method.
出处
《强激光与粒子束》
EI
CAS
CSCD
北大核心
2006年第8期1292-1296,共5页
High Power Laser and Particle Beams
基金
高温高密度等离子体物理国防科技重点实验室基金资助课题(51480040105ZW0804)
关键词
长焦深
轴锥镜
激光等离子体诊断
惯性约束聚变
Long focal-depth
Axicom Laser plasma diagnosis
Inertial confinement fusion（ICF）
