水导激光可适用性光束聚焦模式对比分析

Comparative Analysis of Laser Focusing Modes Applicable to Water Jet Guided Laser

水导激光加工技术中,高质量光束对耦合效率起着关键性的作用。为了解决水-光耦合技术的难题,使水导激光加工技术更好地应用在具有高熔点和高硬脆性的材料的高精密度和低损伤等加工场合,提出自聚焦-球透镜组合聚焦模式和正-负轴棱锥镜组合聚焦模式,并与传统凸透镜聚焦模式进行对比分析。根据三种可适用性聚焦模式,推导相应的ABCD传输矩阵,仿真聚焦模式下的光束特性,并讨论不同聚焦模式下的工业化应用特点。仿真结果表明,正-负轴棱锥镜组合聚焦后的光束束腰半径最小,传统凸透镜聚焦模式聚焦后的光束发散角最小,且三种模式结构不同,都存在各自的优劣性。

In water jet guided laser processing technology,high-quality beams play a key role in coupling efficiency.In order to solve the problem of water-optical coupling technology,the water jet guided laser processing technology can be better used in high-precision and low-damage processing of materials with high melting point and high hardness and brittleness,and the self-focusing-ball lens combination focusing mode and positive-negative axicons focusing mode are compared and analyzed with the traditional convex lens focusing mode.According to the three applicable focusing modes,the corresponding ABCD transmission matrix is derived,the beam characteristics under the focusing mode are simulated,and the characteristics of industrial applications under different focusing modes are discussed.The simulation results show that the beam waist radius of the combined positive-negative axicon lens is the smallest,the divergence angle of the beam after the traditional convex lens focusing mode is the smallest,and the three modes have different structures,and they all have their own advantages and disadvantages.