Amako Jun, Nakano Hidetoshi
Opt Express. 2021 Feb 1;29(3):4488-4503. doi: 10.1364/OE.412397.
We report an achromatic cascade optical system for multifocusing ultrashort pulse beams with a diffractive beam splitter. Distortion compensation requires the removal of pulse front distortions from arrayed pulses, which originate from beam-radius-dependent group delay dispersions. The inclusion of hybrid diffractive-refractive lenses can effectively manage system dispersions. Simple design formulas are derived using the ray-matrix analysis and the designed system is evaluated using 20-fs pulses. We confirm that the hybridized system can remove not only chromatic aberrations but also pulse front distortions, hence improving the system spatio-temporal focusing resolutions. The proposed pulse delivery technique enhances the practicality of materials processing with ultrashort pulses.
我们报道了一种用于多聚焦超短脉冲光束的消色差级联光学系统，该系统采用了衍射分束器。畸变补偿需要消除阵列脉冲中的脉冲前沿畸变，这些畸变源于与光束半径相关的群延迟色散。采用混合衍射折射透镜可以有效管理系统色散。利用光线矩阵分析推导出了简单的设计公式，并使用20飞秒脉冲对设计的系统进行了评估。我们证实，这种混合系统不仅可以消除色差，还可以消除脉冲前沿畸变，从而提高系统的时空聚焦分辨率。所提出的脉冲传输技术提高了超短脉冲材料加工的实用性。
