飞秒激光放大系统中色散补偿的光线追迹精确算法

Accurate Calculation of the Ray-tracing Method for the Dispersion in the Femtosecond Laser Amplification System

对用于计算CPA系统色散的光线追迹法数值算法中出现的误差进行了分析。提出了变步长算法,即在研究CPA系统中高阶色散的补偿问题时,通过选择合理的步长,以减小计算高阶色散的数据振荡,这样明显提高了系统总体色散补偿的计算精度,使计算结果的相对误差从11.8%减小到1.3%,从而使系统色散能够得到更好的补偿,使算法更加完善。通过解析求导结果的检验,证明最佳步长范围为4～8h。

The errors of numerical means by Ray-tracing method for calculating dispersion in the CPA system were investigated.The numerical means with the modified steps was presented.By choosing the steps properly for the compensation of the high-order dispersion in the CPA system,the datas oscillation for computing the high-order dispersion was decreased obviously,which we can distinctly improve total computational accuracy for compensating the dispersion of the whole system.The relative errors of final results had been reduced from 11.8% to 1.3%.By optimizing the steps,the numerical means is more consummate and the dispersion in the CPA system can be compensated more completely.The optimum step range of numerical means had been selected by comparing with the analytical result.