高能光纤激光经准直系统后的光束质量研究

应用光线光学的理论,对透镜的几何像差、热非线性等因素对光纤激光光束质量的影响进行了分析和计算,给出了激光通过多透镜光学系统后,光束质量参数M²与系统参数的一般关系. 研究了高能光纤激光通过准直系统后的光束质量. 研究结果表明,随着激光功率的增大,经准直系统后光束的光束质量存在最佳值,其对应的激光功率与准直系统参数有关,为高能光纤激光准直系统的设计提供了参考. 关键词： 高能光纤激光 光束质量 准直系统 光线光学

Optical quality of high-power fiber laser beams propagating through collimating systems

Within the framework of the ray optics theory, the effects of heating effect and geometric aberration on optical quality of fiber laser beam are calculated and analyzed. An analytical expression for the beam quality parameter M² of fiber laser beam propagating through a multilens optical system is derived as a function of the system parameter. The optical quality of high-power laser beam propagating through a collimating system is investigated. It is shown that a best optical quality can be found as the laser power increases and the corresponding laser power depends on the collimating system parameter. The investigation presents a reference for the design of high-energy fiber laser collimating systems.