设计并搭建了一套基于CCD测量激光光束质量M2的系统。采用CCD测量激光光束在不同位置处的光束直径, 通过非线性最小二乘法拟合测量数据获得光束腰斑直径和远场发散角, 再通过公式计算得到激光光束质量M2。利用本系统测量多组数据, 并与专业M2仪所测的数据进行对比, 二者一致性较好, 表明采用本实验装置测量激光光束质量M2可以有效地替代M2仪。

A system based on CCD to measure laser beam quality was designed and built. CCD was used to measure laser beam diameter at different locations. The collected data samples were then curve fitted to the beam propagation hyperbolic equation. Here the non-linear least squares method was employed to fit the hyperbolic curve, and the results of the fitting procedure yielded laser beam quality M2. To prove the accuracy and reliability of this self-made device, a comparison was made between the measurement results of this device and the specialized instrument M2 equipment, which showed a very good coherence. It indicates that this experiment device can replace M2 equipment.