基于空间光调制器的飞秒激光深微孔加工方法

Depth-micro Laser Drilling Methods Based on Spatial Light Modulator

针对飞秒激光振镜加工系统中聚焦透镜焦深短等原因导致微孔加工深度不足的问题,提出了一种基于高损伤阈值空间光调制器加载菲涅尔透镜相位进行焦点轴向调控的加工方法.通过加载不同焦距的菲涅尔透镜相位图,控制焦点以100μm为间隔进行焦点轴向位移,随着加工深度的增加控制焦点向下移动,并开展了相应的实验加工和测试.实验结果表明,采用该方法在保证高加工质量的前提条件下,在厚度为2 mm的不锈钢样件上实现了直径约为330μm的微孔加工.该方法开辟了二维振镜系统实现超深微孔加工的新探索,在激光加工领域有较好的应用前景.

In the galvo scanning laser drilling systems,the depth of processing is usually limited due to the short focal length.To solve this problem,a method based on high damage threshold spatial light modulator loading Fresnel lens phase is proposed.The focal length of the Fresnel lens is adjusted to change the position of the focus.As the machining depth increases,the focus position moves downward.Then the experiment processing and testing were carried out.The experimental results show that a high quality microhole with a diameter of about 330 microns was machined on stainless steel sample by using the method.The new method uses galvo scanning laser drilling systems and spatial light modulator to process microhole,which has a good application prospect in the field of laser processing.