为了提高激光并行加工中多焦点阵列的均匀度及可操控性,基于物镜聚焦系统的矢量傅里叶变换特性,设计了一种矢量迭代优化相位算法。基于此算法,可以制备具有高均匀度的多焦点阵列,且阵列中每个焦点的空间位置可精确调控。数值模拟与实验结果表明,优化出的相位可以用来制备具有高均匀度的多焦点阵列。利用自主搭建的基于空间光调制器的飞秒激光加工系统,以金膜为例,验证了激光并行加工的可行性。实验结果表明,利用所提算法,可以实现具有任意排列结构的多焦点阵列的并行激光加工。利用动态加载相位图的方式,可以实现动态扫描加工。

To improve the uniformity and controllability of the multifocal array in laser parallel fabrication, a vector iterative optimization phase algorithm is proposed based on the property of the vector Fourier transform in an objective focusing system. Based on this iterative algorithm, a multifocal array with high uniformity can be produced and the position of each focal spot can be precisely controlled. The numerical simulation and experimental results show that the optimized phase can be utilized to generate a multifocal array with high uniformity. Furthermore, applying the homemade femtosecond laser fabrication system based on a spatial light modulator and taking gold films as the sample, we confirm the validity of laser parallel fabrication. The experimental results demonstrate that using the proposed algorithm, one can achieve the laser parallel fabrication based on multifocal array with an arbitrary arrangement structure. In addition, the dynamic scanning laser fabrication can also be realized by dynamically loading phase patterns.