【摘要】 元件的像差和加工装配误差会影响通过其中的超短脉冲的时空特性。在不考虑介质的非线性作用时,基于傅里叶频谱理论并结合光线追迹和衍射理论,发展了一种有效的数值方法仿真超短脉冲通过光学系统的时空传输特性。以一个引入实际误差的2片式聚焦透镜组为例,分析了入射中心波长为800nm,脉冲宽度为30fs的高斯型超短脉冲通过该系统的传输过程,并通过实验测量了该系统在焦点处的脉冲时间宽度和焦斑大小,并与仿真结果进行了比对。结果表明,该方法不仅可以很好地仿真分析实际光学系统中超短脉冲的时空传输效应,也使得超短脉冲系统的优化设计成为可能,同时也为提出加工要求和合理的公差分配提供了指导意义。更多还原

【Abstract】 The spatial-temporal property of ultrashort pulse is greatly influenced by optical aberrations,manufacturing surface-profile errors as well as element decenter and tilts when propagating through real optics.Hence it is necessary to develop a powerful analytic tool to simulate these effects.An efficient numerical algorithm based on a combination of wave theories and geometrical ray-tracing to simulate the propagation of ultrashort laser pulse through real optics is proposed.Using this tool,the spatial-temporal evolution of a Gaussian temporal envelope pulses with initial durations of 30 fs and a carrier wavelength of 800 nm through a specific real optics is modeled,in which both the geometrical aberrations and manufacturing surface-profile errors of the optical elements are considered.Consequently,a comparative analysis on focusing properties of the pulse such as temporal envelope and focal size retrieved by simulation and experimental measurement is carried out at the focus for homogeneous illumination beams.更多还原