Following femtosecond (fs) laser pulse irradiation, the formation of a new type of low-spatial-frequency laser-induced periodic surface structure (LSFL) patterns, namely, omnidirectional LSFLs (OD-LSFLs) with the periodic ordering of their orientations, are investigated on Ni in this Letter. Using a liquid crystal polymer patterned depolarizer, we periodically rotate the polarization of fs laser pulses across the laser spot and create OD-LSFLs by raster scanning fs laser pulses. We also show that the period of the OD-LSFL orientation rotation can be controlled with the defocused distance, and OD-LSFLs can significantly expand the viewing angle of the structural colors in the azimuthal direction without noticeable color degradations.

中文翻译：

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通过全向飞秒激光诱导的周期性表面结构对金属表面进行旋转对称着色。

在飞秒（fs）激光脉冲辐照之后，形成了一种新型的低空间频率激光诱导的周期性表面结构（LSFL）模式，即具有方向周期性排列的全向LSFL（OD-LSFL）。在这封信中对镍进行了调查。使用液晶聚合物图案化的去偏振器，我们周期性地旋转fs激光脉冲的偏振光跨整个激光点，并通过光栅扫描fs激光脉冲来创建OD-LSFL。我们还表明，可以通过散焦距离控制OD-LSFL方向旋转的周期，并且OD-LSFLs可以显着扩展结构颜色在方位方向上的视角，而不会出现明显的颜色下降。